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Southwest Climate Outlook June 2018 - Climate Summary

Thursday, June 21, 2018

Precipitation and Temperature: The Southwest was characterized by below-average precipitation in May, ranging locally from record driest to near average (Fig. 1a). Temperatures were above average to much-above average across most of the Southwest, with small pockets of record-warm conditions in the northwest corner of New Mexico and along the eastern edge of the state (Fig. 1b). The March through May period exhibited similar patterns of mostly drier-than-average to record-dry precipitation (Fig. 2a) and much-above-average to record-warm temperatures (Fig. 2b). Water-year precipitation to date (Oct 2017 – May 2018) highlights how dry most of the region has been at a longer timescale, with below-normal to record-dry conditions across Arizona and above-normal to record-dry conditions in New Mexico (Fig. 3).

Monsoon & Tropical Activity: The Pacific tropical storm season got off to a strong start with Aletta and Bud, the former as an early start to the season in May, and the latter bringing well-above-normal June precipitation to parts of the Southwest (see Monsoon/TS tracker).

Snowpack & Streamflow Forecast: Snow was all but gone from the Southwest by June, and snow water equivalent (SWE) for the Upper Colorado River Basin remain below average, with only the upper Great Basin and Pacific Northwest having any semblance of above-normal snowpack. Warm and dry conditions continue to affect streamflow and runoff timing – a pattern that extends to the Upper Colorado River Basin, where streamflow forecasts are all well-below average.

Drought: Drought-designated areas continued to expand from last month. In the June 21 U.S. Drought Monitor, Arizona and New Mexico saw further increases in the extent and intensity of drought (Fig. 4). These designations reflect short-term precipitation deficits, above-normal temperatures at monthly and seasonal timescales, and longer-term drought that tracks the cumulative effect of extended periods of warmer- and drier-than-normal conditions. The surge of tropical storm activity (Bud) in mid-June brought a welcome reprieve from ongoing dry conditions, but the next realistic hope for drought relief is the summer monsoon. The extent of its impact will depend on when it starts and how much (and how regularly) precipitation actually falls.

Wildfire: The National Significant Wildland Fire Potential Outlook for June identified above-normal wildland fire risk across the Southwest except for eastern New Mexico and far northwestern Arizona, while the outlook for July calls for the fire risk to return to normal (Fig. 5a-b) in anticipation of monsoon moisture abating the risk. Southeastern Arizona and portions of New Mexico received precipitation linked to the remnants of Tropical Storm Bud, but regional patterns are not indicative of an early start to widespread monsoon activity (see Monsoon Tracker). A late start to the monsoon could extend the fire-risk window, especially if long periods of dry lightning—a major ignition risk in June and July—precede precipitation. The region has been relatively fortunate in 2018, with less lightning-caused fire activity than might have been expected (Fig. 6), given the exceptionally warm and dry conditions over the winter and above-normal fine-fuel loading and continuity.

El Niño Tracker: Neutral conditions are present in oceanic and atmospheric indicators, and longer-term outlooks indicate increasing chances of an El Niño event in 2018. Both the timing and the probability of an El Niño event are still uncertain, but most forecasts highlighted an increased chance of El Niño forming compared to last month, with now nearly twice the chance compared to ENSO neutral conditions (see ENSO tracker). Notably, there is nearly zero chance of a La Niña event in 2018.

Precipitation and Temperature Forecast: The three-month outlook for June through August calls for increased chances of above-normal precipitation in Arizona and western New Mexico, with equal chances in central and eastern New Mexico (Fig. 7, top). The outlook calls for increased chances of above-average temperatures for the entire Southwest (Fig. 7, bottom).


Online/Image Resources

  • Figures 1-2 -National Centers for Environmental Information -ncei.noaa.gov
  • Figure 3 - Western Regional Climate Center - wrcc.dri.edu
  • Figure 4 - Climate Assessment for the SW - climas.arizona.edu
  • Figure 5 - U.S. Drought Monitor - droughtmonitor.unl.edu
  • Figure 6 - National Interagency Fire Center - nifc.gov
  • Figure 7 - NOAA - Climate Prediction Center - cpc.ncep.noaa.gov

Rainlog Climate Summary – August 2017

Tuesday, September 5, 2017

After an exceptionally wet July for many areas across Arizona, monsoon storm activity slowed down to a crawl leading to unusually dry conditions over the past month. August is typically the wettest month during the summer monsoon season in Arizona and the lack of thunderstorm activity stands out against the frequent and heavy activity that characterized much of the month of July. There were three days in August where no rainfall fell anywhere in Arizona (August 8th, 16th, and 18th), a strange and unusual occurrence in the heart of the monsoon season. The long-lived surge of moisture from the Gulf of California and reasonably favorable position of the upper level high pressure system that supported the frequent thunderstorm activity in July broke down in early August leading to much less favorable conditions for monsoon activity. The upper level high retreated south into Mexico ushering in drying upper level winds from the southwest and suppressing much of the thunderstorm activity across the state. Some higher elevation areas have been able to fire off afternoon thunderstorms on a handful of days in August, but most lower elevation areas have been left out of the action.

The overnight period of August 12th into the morning on the 13th was one of the heavier, widespread rain events that occurred during the month. Tropical Storm Jova passed west of Baja California around this time helping to push a slug of moisture up into southern Arizona. This provided the fuel for an outbreak of heavy thunderstorm activity in the overnight hours on the August 12th. Rainloggers in the Tucson metro area reported widespread amounts in excess of 1” with a handful of reports above 2.5”. Reports of daily totals in excess of 1” extended from southeast Arizona (Bisbee, Douglas, Sierra Vista) up through Phoenix and as far north as Prescott with this event.  

Overall, August precipitation totals look bleak across much of Arizona with respect to average levels. Some isolated areas have received average to above-average August totals, but most of Arizona has observed less than 75% of average with some locations (far northeast and parts of central AZ) seeing less 25% of their typical average total August precipitation. The monsoon season typically winds down through the first couple weeks of September, but the threat of tropical storms and associated moisture will keep the prospect of additional precipitation alive for this season.


https://rainlog.org/map

SW Climate Outlook - ENSO Tracker - Aug 2017

Sunday, August 20, 2017

Oceanic and atmospheric indicators remain within the range of neutral (Figs. 1-2). Seasonal outlooks and forecasts generally agree that ENSO-neutral conditions are the most likely outcome through winter 2017-2018. On Aug. 10, the Japanese Meteorological Agency (JMA) identified a continuation of ENSO-neutral conditions with a 60-percent chance of El Niño conditions until winter 2017-2018. On Aug. 10, the NOAA Climate Prediction Center (CPC) observed that oceanic and atmospheric conditions remained within the range of ENSO-neutral conditions, and that “the majority of models favor ENSO-neutral for the remainder of 2017.” They identified an 85-percent chance of neutral conditions through September 2017, and a 55-percent chance through February 2018. On Aug. 15, the Australian Bureau of Meteorology ENSO tracker remained at neutral/inactive, highlighting that every indication (models and forecasts) suggested ENSO-neutral conditions through 2017. On July 20, the International Research Institute for Climate and Society (IRI) and CPC identified a high likelihood of ENSO neutral conditions for the rest of 2017 (Fig. 3). The North American Multi-Model Ensemble (NMME) is ENSO-neutral as of August 2017. The model spread indicates a range of outcomes for the rest of 2017 (Fig. 4), but the ensemble mean indicates ENSO-neutral as the most likely outcome.

Summary: As with last month, ENSO indicators remain well within the bounds of ENSO-neutral, and there is little to suggest any other outcome in winter 2017-2018. An interesting detail has emerged from a few of the forecast discussions, however: the appearance of a slight uptick in the likelihood of a La Niña event in 2017-2018, running counter to discussion of the last few months. What’s going on? In Fig. 3, subtracting the current forecast percentage (bars) from the seasonal climatological probability percentage (lines) flattens the plot and reveals the deviation from normal climatology these forecast percentages represent (Fig. 5). Under this formulation, neutral conditions are forecast well above their climatological average through winter 2017-2018, while both El Niño and La Niña conditions are below their climatological average. This corresponds with current forecasts discussed above, and given the expected uncertainty associated with longer-term forecasts, the forecast percentages converge on climatological averages by the Mar-Apr-May period of 2018.


Online Resources

CLIMAS Southwest Climate Outlook - Apr 2017 Climate Summary

Thursday, April 20, 2017

Precipitation & Temperature: March precipitation totals were average to below average in most of the Southwest except for the northeastern corner of New Mexico (Fig. 1a). March temperatures were much-above average across the entire Southwest, with record warm temperatures in the southeast corner of Arizona and most of New Mexico (Fig. 1b). April precipitation to date has been below average for much of southern Arizona and New Mexico (Fig. 2), while April temperatures have been between 0 and 6 degrees above normal for most of the region. Water year precipitation has been normal to above normal for most of Arizona and New Mexico, aside from a dry region along much of the Arizona-Mexico border (Fig. 3).

Snowpack & Water Supply: Warm temperatures across the West (particularly in the Upper Colorado River Basin) have begun to put a dent in the snowpack and snow water equivalent (SWE) values this month, especially in warmer low-elevation areas. Most of the stations in Arizona and New Mexico have dipped to below 50 percent of normal SWE, a decline that is also reflected in the Upper Colorado River Basin region of Utah and Colorado (Fig. 4). Snowpack and SWE remain markedly above average in other locations in the West, particularly in much of the Great Basin and the Sierras in CA. The persistent warm temperatures of early 2017 combined with the ample snowpack are resulting in similarly remarkable streamflow forecasts, as well as improvements in reservoir storage values (see reservoir levels).

Drought: While much of the West has seen improvements in drought conditions (notably, California declared an end to its drought), southern Arizona and New Mexico have experienced an increase in drought designation, especially near the borderlands, owing to near-record- to record-warm temperatures and very little precipitation in the last few months (Fig. 5). Thus the wetter-than-normal conditions that helped reduce drought conditions across much of the West (see Fig. 3), provided only short-lived recovery in southern Arizona and New Mexico. 

Environmental Health & Safety: The impressive wildflower bloom has continued, fueled by a combination of fall and early-winter precipitation and sustained warm temperatures over the last few months. These conditions have also resulted in a particularly bad year for allergies, with sustained growing periods leading to high pollen levels across the region. The warm and dry weather continues to produce dry and dusty conditions, again resulting in numerous closures of interstate highways when dust conditions are severe. The temperature and precipitation patterns of the past six months have also contributed to elevated levels of fine fuels, so with temperatures on the rise and precipitation on the wane, fire managers will continue to keep watch very carefully, especially on days when high winds and low dew-point temperatures create conditions favorable for fire ignition and spread.

El Niño Southern Oscillation: Current forecasts suggest ENSO-neutral conditions continuing through the spring and early summer, with increasing chance of an El Niño event during the second half of 2017 (see ENSO Tracker).

Precipitation & Temperature Forecast: The April 20 NOAA Climate Prediction Center’s outlook for April calls for equal chances of above- or below-average precipitation, and increased chances of above-average temperatures across the region.  The three-month outlook for May through July calls for equal chances of above- or below-average precipitation in most of Arizona and increased chance of above-average precipitation in New Mexico and the remainder of Arizona (Fig. 6, top), along with increased chances of above-average temperatures across the region (Fig. 6, bottom).

Life between Hope and Despair: Climate Change Impacts in Coastal Bangladesh

Monday, December 19, 2016

Traveling across southwest coastal Bangladesh is not easy. With limited transport infrastructure and facilities, people might end up spending an entire day or night just to travel small distances. In the last week of May (2016), when I arrived coastal city Kuakata in Patuakhali district, literally I spent the whole night to travel ca. 150 miles from Khulna (a regional big city, which is 170 miles southwest of the capital Dhaka). It was a rainy early morning in Kuakata. However, it didn’t took much time to realize local vulnerability to climate impacts. I went to the Kuakata sea beach, and saw how local people are living with the risks of rising tides and coastal erosion. I clearly understood why for local people climate change is not an issue of scientific or political discourse; for them, it is the reality.

After spending few days and talking with local people, I realized local livelihoods are affected by various climate related risks, which can be broadly categorized into two major groups: (1) slow onset climate events such as sea level rise and salinity intrusion in land and groundwater and (2) extreme climate events such as tropical cyclones, coastal floods. Locally more information is available on extreme climate events than slow onset climate impacts, even though those can have long-term impacts on local livelihoods. It is not rare that people from the region are forced to migrate to some other regions, because locally lands are not any more arable due to increasing saltwater intrusion in local lands and ground water. In some areas, people have restricted access to drinking water because of the same reason. Sea level rise, water logging, coastal floods, tropical cyclones are among the long list of disasters that local people experience in their daily life.

A local NGO, ADAMS[1] (Association Development Activity Manifold Social Work) which is working in ten districts across southern Bangladesh, provided me invaluable logistics supports in the field. They helped me to travel into the remotest corners in the region and created opportunities for numerous interactive discussions with the local people. I interacted not only with local farmers or fishermen, I got the opportunity to talk with local government representatives, community activists, and many other village people. I was trying to link my text book references with local climate contexts. It was clearly apparent to me that even though climate change is often presented as a long-term macro-scale process, the reality is manifested and experienced as real-time local level alterations in climate variability.

However, it seemed to me that the future of humanity is now present in the coastal Bangladesh. If the people in this region can sustain, than many other parts of the world that are facing similar challenges can also sustain or thrive under shifting pattern of weather/climate. The future of human race largely depends on how we – social systems in general – will react to the changing patterns of climate. Human responses to climate variability and change can be identified as adaptation. Unfortunately, in coastal Bangladesh not all people have the similar capacities to respond to climate stresses. Some communities or people will do better than others.

Usually, in low-income developing countries these differential capacities to climate adaptation are largely shaped by the deep-rooted structural challenges, such as social marginalization, religious and ethnic exclusion, unequal land ownership, social relationship. In addition to climate risks, these context-specific structural challenges also contribute in determining individual/household capacity to respond to climate stresses.

We need to understand this complexity of human responses to climate change in the local level, and can employ the concepts of vulnerability, adaptation, and resilience, to better identify how responses to climate pressures vary among different households and communities and how we can provide appropriate adaptation solutions. We need to critically analyze what factors improve adaptation decisions, or, specifically enhance and increase adaptive capacity of the local people who are exposed to climate risks. Adaptive capacity is measured in terms of access to assets and resources such as information, social capital, power, diversifications, etc. For my doctoral research, I will explore the role of user-inspired climate services in promoting local adaptation decision-making.

I put “people” at the center of my months long pre-doctoral exploratory field research in coastal Bangladesh, since they are at the frontline of climate change impacts. They live with climate extremes, and realize changing patterns of climate much earlier than we, the researchers, can find. I incorporated local insights on building my climate knowledge on vulnerability and adaptive responses. I found local innovations on farming and livelihood adjustment under climate stresses, such as farming in elevated lands.

When I return to Tucson, AZ, which is quite a different environment with different climatic challenge, I came with new insights, questions, and curiosities. Thanks to CLIMAS’ Climate & Society Graduate Fellow Program for conducting this important work.  I often asked myself, did my field visit in Bangladesh made me a more optimistic or a more pessimistic person than I was before. Maybe I was puzzled with the complex nature of climate-society interactions in the region. However, I am fairly confident with concerted efforts among science, society, industry and policy, and as human society, we will thrive and we can survive even in face of largest human challenge that we have ever confronted.

[1] http://www.adams-bd.org/

Southwest Climate Outlook August 2016 - Climate Summary

Thursday, August 18, 2016

Precipitation and Temperature: July precipitation totals were below average across most of Arizona and New Mexico in the past 30 days (Fig. 1a), due in part to an extended break in monsoon activity. July temperatures were above average across nearly the entire region (Fig. 1b), linked to global trends that saw record-warm temperatures in 2016 and to regional patterns of warmer and drier conditions that correspond to the aforementioned break in monsoon activity. August precipitation to date is average to above average for most of Arizona and portions of New Mexico (Fig. 2), partly linked to moisture associated with Tropical Storm Javier that resulted in heavy precipitation in parts of the Southwest. In August, temperatures have been mostly average to below average in Arizona and mostly above average in New Mexico (Fig. 3).

Monsoon: A strong start for the monsoon in late June was followed by an extended break in activity for much of July. The end of July saw another multi-day system that brought frequent storm activity to the region, particularly in southeastern Arizona, which has seen some of the heaviest monsoon activity this year (see Monsoon Tracker). Seasonal totals to date for New Mexico generally have been below average, although August rainfall has helped make up some of the precipitation deficit.

Drought & Water Supply: Long-term drought persists across the Southwest (Fig. 4), reflecting multiple years of drought conditions and accumulating precipitation deficits. In the Aug. 16 U.S. Drought Monitor, most of Arizona was designated as experiencing moderate drought (D1), while most of New Mexico was designated as abnormally dry (D0). This pattern is unlikely to reverse in the short term, especially with a weak La Niña event likely occurring this fall into winter, which could bring warmer and drier conditions to the Southwest. Water year precipitation to date is below average in much of the Southwest, particularly in Southern California, most of southern Arizona, and western New Mexico (Fig 5).

La Niña: Sea surface temperature anomalies and atmospheric patterns all indicate ENSO-neutral conditions. Uncertainty remains as to whether an actual La Niña event will occur, but current model consensus points toward the formation of a weak La Niña event between now and October that is expected to last through winter 2017 (see La Niña Tracker).

Wildfire: Cooler and wetter-than-average conditions linked to the lingering effect of El Niño tamped down early-season fire activity in April and May. Fire activity picked up in June and July, but precipitation from cold front, monsoon, and tropical storm activity, as well as increased relative humidity across the region, helped limit the risk of severe wildfire. As of August, wildland fires had burned approximately 220,000 acres in Arizona and 274,000 acres in New Mexico. Favorable weather conditions permitted fire managers to let a number of fires burn for beneficial use to reduce future wildfire risk.

Precipitation & Temperature Forecasts: The July 21 NOAA-Climate Prediction Center’s seasonal outlook for September calls for increased chances of above-average precipitation for most of Arizona and western New Mexico (Fig. 6) and increased chances of above-average temperatures across the western U.S. (Fig. 6). The three-month outlook for September through November calls for increased chances of above-average temperatures across the U.S.— and the Southwest in particular—while calling for equal chances of average, above-average, or below-average precipitation.

Southwest Climate Outlook March 2016 - Last Gasp for El NIño?

Thursday, March 17, 2016

Precipitation & Temperature: Over the past 30 days, precipitation totals were well below average for most of the southwestern U.S. (Fig. 1). Despite anticipation for above-average precipitation this winter due to the strong El Niño event, a ridge of high pressure diverted moisture around the Southwest for much of the last 60 days. The resulting precipitation patterns look more like La Niña than El Niño, as the coastal Northwest and northern California have recorded well above-average precipitation and the Southwest has been very warm and dry (see El Niño Tracker). Temperatures in February were well above average for most of the Southwest, setting numerous high-temperature records, especially in southern Arizona and coastal Southern California (Fig. 2).

Image Source - Advanced Hydrologic Prediction Service

Image Source - NOAA National Centers for Environmental Information

Drought: Long-term drought persists across much of the Southwest, and recent warm and dry conditions have done little to improve regional outlooks on short-term drought (Fig. 3). There was hope that a strong El Niño might reduce precipitation deficits, but multi-year droughts, such as those experienced during much of this century so far, will require more sustained above-average precipitation over multi-year periods to fully recover. 

Image Source - U.S. Drought Monitor

Snowpack & Water Supply: This winter, below-average precipitation and above-average temperatures have dropped snow water equivalent (SWE) percent of normal to well below average in Arizona and southern New Mexico, with values ranging between 0 and 25 percent of normal. Northern New Mexico and much of the Upper Colorado River Basin are faring somewhat better, with SWE values between 75 and 110 percent of normal (Fig. 4). It remains to be seen how the rest of winter and spring will play out in high elevation areas, and how this will affect reservoir storage in the region (See reservoir storage information).

Image Source - Western Regional Climate Center

El Niño Tracker: With winter winding down and little on the horizon to indicate a shift towards a wetter signal, this El Niño event is shaping up to be a bit of a disappointment compared to forecasts and media characterizations that dominated the run up to the actual event. Expectations for a strong El Niño had been high, beginning with the false start of this El Niño event in 2014–2015, and continuing with a general sense of the potential a strong El Niño event could have to mitigate ongoing drought conditions (see expanded El Niño Tracker).

Environmental Health & Safety: The Southwest has been awash in color as flowering plants exploded to life, fed by the increased precipitation during fall 2015 and kickstarted by above-average temperatures of the past month or so. As a result, pollen counts are up, and as dry conditions persist, we can expect increased dust and particulate matter as well.  Wildfire also looms on the horizon, as growth spurts in fine fuels last fall and dry conditions this winter and spring have combined to increase fire danger classifications across the Southwest (Fig. 5). 

Image Source - Wildland Fire Assessment System

Precipitation & Temperature Forecast: The March 17 NOAA-Climate Prediction Center three-month seasonal outlook calls for increased chances of above-average precipitation for most of the Southwest (Fig. 6, top), and increased chances of above-average temperatures across most of the western United States (Fig. 6, bottom).

Image Source - NOAA/NWS - Climate Prediction Center

2015-2016 El Niño Tracker - Feb 2016

Monday, February 22, 2016

Originally published in the Feb 2016 CLIMAS Southwest Climate Outlook


El Niño conditions continued for a 12th straight month, but we have passed the peak intensity of one of the strongest El Niño events on record. This does not mean that El Niño is over, though. Despite the recent warm and dry conditions in the Southwest, we are likely to see more weather events associated with El Niño conditions through spring 2016. In monitoring and forecast discussions, we continue to see persistent sea surface temperature (SST) anomalies (Figs. 1–2) and enhanced convective activity in the central and eastern Pacific, and most models forecast that this El Niño event will continue through spring or early summer. Precipitation and temperature outlooks mirror this forecast, calling for increased probabilities of precipitation across most of the southern U.S.

On Feb. 10, the Japan Meteorological Agency identified ongoing El Niño conditions as having passed their “mature” stage in the equatorial Pacific and predicted that this remarkably strong event would gradually weaken to neutral conditions by summer.  On Feb. 11, the NOAA-Climate Prediction Center (CPC) extended its El Niño advisory and identified the current atmospheric and oceanic anomalies as reflecting a strong El Niño that will persist through most of the spring before transitioning to ENSO-neutral conditions in late spring or early summer, with increasing chances of La Niña conditions by early fall. On Feb. 16, the Australian Bureau of Meteorology maintained its tracker at official El Niño status, but noted that deceasing temperature anomalies and building trade winds are indicators of this event’s gradual decline. On Feb. 18, the International Research Institute for Climate and Society (IRI) and CPC forecasts indicated a gradual weakening of El Niño from late spring into summer (Fig. 3), and reiterated that this El Niño would likely gradually decline, with lingering effects and impacts through spring 2016. The North American multi-model ensemble currently shows a strong event extending into early spring with gradual weakening to neutral conditions by late spring or early summer (Fig. 4).

In the Southwest, seasonal forecasts and past events suggested we should see well above-average cumulative precipitation totals throughout our cool season (Oct–Mar). However, the past 30–40 days of mostly warm and dry conditions, including numerous record-setting high temperatures combined with the melting of our previously abundant mountain snowpack, makes it hard not to feel like this El Niño is a “bust.” Is this a fair assessment, or does this simply reflect the difficulty of interpreting climate events (e.g., El Niño conditions) on a weather timeline? In previous discussions, we’ve highlighted the fact that we should expect periods of inactivity between storms, but we were hopeful those inactive periods would be on the order of days to a week, not weeks to a month. Even so, the default state for the desert Southwest is dry, so even a strong El Niño event can only alter that system so much, and past events do show periods of extended inactivity. Precipitation during the 1997–1998 El Niño event (strongest on record) was well below average in January 1998 (Fig. 5), with an extended run of dry days before it roared back to life from February through April 1998 (Fig. 6). If we look at cumulative cool-season precipitation during our current El Niño event (October 2015 – January 2016), our precipitation totals are at or above average (Fig. 7), and January 2016 was less dry than it may have seemed thanks to an active first week of the month (Fig. 8).

Even though the 2015–2016 El Niño event peaked in December 2015, the impacts in the Southwest lag behind this spike in intensity, which means we look to late winter and early spring as the most likely times for increased storm activity associated with the El Niño signal. We won’t be able to fully evaluate the 2015–2016 El Niño event until we know how much rain and snow fell over the entire cool season, and given past events, our best bets for seeing above-average precipitation will be in February and March. In the short term, we are left waiting for the jet stream to shift to a favorable pattern that funnels moisture into the Southwest, rather than directing it around us. 

Southwest Climate Outlook - February 2016

Thursday, February 18, 2016

Originally Published in the Feb 2016, CLIMAS Southwest Climate Outlook


Precipitation: Over the past 30 days, precipitation totals were mostly below average for most of Arizona and much of New Mexico (Fig. 1). Since early January, we have seen persistent warm and dry conditions, linked in part to a ridge of high pressure. Similarly, over the last 90 days, precipitation has been average to below average across much of the Southwest (Fig. 2). However, if we shift our focus to the water year (since Oct. 1), we see precipitation totals much closer to average, and even above average across much of New Mexico (see El Niño Tracker, for more details).

Temperature: Temperatures in January were near average for most of Arizona and New Mexico, but much warmer in February, with much of the region recording above-average temperatures (Fig. 3). The same high-pressure ridge that limited our opportunity for incursions of moisture has facilitated these above-average temperatures, including record-warm days across the region in early February.

Snowpack and Water Supply: Warmer temperatures and below-average precipitation have reduced our previously impressive snow water equivalent (SWE) values back to near average (90–110 percent of normal) across much of the Southwest, with values dipping as low as 50–75 percent of normal across portions of southern Arizona and New Mexico (Fig. 4). This warm-up and dry-out is likely to taper at some point this season, but it remains to be seen how much additional winter precipitation will fall. Given past strong El Niño events, it is reasonable to expect at least some additional precipitation from now into spring. 

Drought: Long-term drought conditions persist across much of central and eastern Arizona and the western edge of central New Mexico (Fig. 5). We saw a few runs of average to above-average precipitation, which helped mitigate some of the short-term drought conditions, but multi-year droughts, such as those we experienced during much of the 21st century, will require more sustained above-average precipitation over multi-year periods to fully recover.

El Niño Tracker: We are in the middle of a strong El Niño event, forecast to remain in place through spring 2016. Outside of El Niño’s influence, winter conditions for the Southwest are relatively dry, but the extended hiatus in winter storm activity over the last month is longer than expected. The forecast models for the remainder of February look warm and dry, but this pattern should break eventually, resulting in more winter precipitation events and likely a higher than average cumulative precipitation total by the end of our cool season (see El Niño Tracker).

Precipitation & Temperature Forecast: The February 18 NOAA-Climate Prediction Center three-month seasonal outlook continues to predict above-average precipitation for most of the Southwest this winter, centered on Arizona, New Mexico, and West Texas (Fig. 6, top). Temperature forecasts are split, with elevated chances for above-average temperatures along the West Coast and the Pacific Northwest and increased chances for below-average temperatures centered over Texas and into New Mexico (Fig. 6, bottom).


Also in this issue:

¿Cómo se determina la fuerza de El Niño?

Tuesday, February 2, 2016

Existen varios índices o indicadores para seguir el desarrollo de ENSO (La Circulación del Sur El Niño) a través del Océano Pacifico y para determinar si los patrones atmosféricos reflejan las condiciones típicas de El Niño, La Niña, o condiciones neutrales. Algunos índices solo toman en cuenta la atmósfera, por ejemplo el índice “Southern Oscillation Index.”  Otros solo examinan el océano (por ejemplo “Niño 3.4 index,”) y algunos examinan la combinación de ambos (por ejemplo el “Multivariate ENSO Index.”)  Todos los índices tienen diferentes fortalezas y debilidades, pero los índices que se basan en el océano tienden a reflejar la evolución lenta de ENSO, los patrones de los cambios en la temperatura superficial del océano, los cuales pueden tener gran efecto en los patrones del tiempo globales por muchos meses y estaciones.

El Centro de Predicción Climático del NOAO usa el Índice Oceánico El Niño (ONI) – la media actual de las anomalías de 3 meses de la temperatura superficial del mar en una parte clave del mar ecuatorial Pacifico desde al oeste de la línea de fecha internacional hacia 120 longitud oeste.

Seguimiento de las temperaturas del mar de esta región es buena indicación si la convección (impulsada por aguas cálidas) se está cambiando y se puede cambiar atípicamente más lejos hacia el oriente a través el ecuador durante las condiciones de El Niño, o lejos hacia el oeste durante los eventos de La Niña.  Los valores numéricos de ONI van desde -2.5 lo cual indicaría un evento fuerte de La Niña, hasta 2.5, lo cual indicaría un evento fuerte de El Niño.  El NOAA-CPC hace distinción entre la aparición de las condiciones de El Niño o La Niña – valores numéricos de ONI de +.5 (El Niño) o de -.5 como límite en la escala mensual además de otras indicaciones atmosféricas como cambios en los vientos y patrones de lluvia comparado con un evento bien desarrollado que puede tardar por muchos meses o estaciones.  Un evento requiere que los valores numéricos de ONI sean más que los límites de +0.5 o -0.5 por lo menos cinco meses consecutivos.  (Más detalles en climate.gov)

Como es que La Oscilación del Sur “El Niño” (ENSO) afecta los patrones del tiempo de la región suroeste?

Monday, February 1, 2016

Los eventos El Niño y La Niña se desarrollan generalmente entre Abril y Junio, por lo cual quiere decir que la región suroeste de los Estados Unidos siente los efectos más prominentes de los cambios de la circulación de ENSO durante el invierno y hasta los principios de la primavera. La influencia de ENSO en el tiempo de la región suroeste se correlaciona con su capacidad de cambiar la posición de la corriente en chorro – los vientos en altura que dirigen los sistemas de tormentas y dictan la posición de las áreas de alta y baja presión. Durante los eventos “El Niño,” la corriente en chorro sobre el Océano Pacifico se desarrolla menos ondulada y se separa en una corriente subtropical cerca del ecuador y una corriente polar más débil.  Esto puede resultar en mayor número de tormentas y precipitaciones superiores a la media en la región suroeste durante el invierno y hasta los principios de la primavera.  Los eventos “La Niña,” frecuentemente traen condiciones invernales más secas que el promedio en la región del suroeste, cuando la corriente en chorro se curva y se cambia hacia el norte, desviando las tormentas y precipitación fuera de la región.  Un evento El Niño no garantiza un invierno con alta precipitación, igual como un evento La Niña no consecuentemente causa condiciones secas, pero estos son los patrones más asociados con estos eventos. 

El impacto de ENSO sobre el tiempo durante el verano no es tan claro, pero los eventos El Niño pueden retrasar la temporada del monzón en Arizona y Nuevo México al debilitar y reposicionar la alta presión subtropical que guía la humedad hacia la región suroeste.  Los eventos El Niño también influyen el desarrollo y la fuerza de tormentas tropicales del Océano Pacifico del este, y la humedad asociada con estas tormentas tiene la potencial de causar más lluvia que la precipitación media en la región, típicamente a fines del verano o en el otoño.

Las anomalías de precipitación influidas por ENSO varían geográficamente, y las regiones de Arizona y Nuevo México tienden a tener más notable precipitación positiva durante los eventos El Niño comparadas con las regiones del norte.  Durante un evento La Niña, el patrón general es el opuesto, con la precipitación reducida en la región del suroeste.

Figura: Los eventos El Niño y La Niña causan que el pasaje de las corrientes en chorro se muevan sobre los Estados Unidos en diferentes lugares, frecuentemente causando inviernos húmedos durante los eventos El Niño e inviernos secos durante los eventos La Niña en el suroeste.  Imagen modificada de la Administración Oceánica y Atmosférica Nacional (NOAA).

Qué es ENSO - La Oscilación del Sur “El Niño”?

Thursday, January 28, 2016

“El Niño” y “La Niña” son parte de la oscilación del sur El Niño, (ENSO por sus siglas). ENSO es una fluctuación natural de las temperaturas superficiales del mar y la presión superficial del aire del Océano Pacifico Tropical entre el este y oeste.  Durante un evento “El Niño,” los vientos alisios del este se debilitan, permitiendo que el agua superficial más cálida  del Océano Pacifico Tropical del oeste corra  hacia el este.  Durante un evento “La Niña,”  estos vientos alisios se intensifican, causando que el agua cálida del este no pueda correr hacia el oeste y por consiguiente que el agua cálida superficial del este se apile.  Grandes áreas de baja presión superficial del aire y precipitación convectiva siguen el agua cálida al migrar a través del Océano Pacifico Tropical, alterando los patrones de circulación atmosférica (por ejemplo, la Circulación Walker), que pueden influir el tiempo de todo el mundo. (Figura 1)

Figura 1: Eventos El Niño causan que el pasaje invernal de la corriente en chorro  se mueva sobre la región del suroeste, generalmente entregando más lluvia y nieve invernal en la región. Imagen modificada de la Administración Oceánica y Atmosférica Nacional (NOAA).

El Niño Tracker - Jan 2016

Friday, January 22, 2016

El Niño conditions continued for an 11th straight month, putting us squarely in the middle of a strong El Niño event that will be among one of the strongest events on record. Forecasts focused on the persistence of sea surface temperature (SST) anomalies (Figs. 1–2) and weakened trade winds, enhanced convective activity in the central and eastern Pacific, and El Niño-related ocean-atmosphere coupling. Models continue to forecast a strong El Niño event that will last through spring 2016, but we are starting to see signs of decline in the overall strength of the event.

On Jan. 12, the Japan Meteorological Agency identified ongoing El Niño conditions as having reached their “mature stage” in the equatorial Pacific in November–December 2015, with likely gradual weakening during the months ahead. On Jan. 14, the NOAA-Climate Prediction Center (CPC) extended its El Niño advisory and said the current atmospheric and oceanic anomalies reflect a strong El Niño that will persist through most of the spring, transitioning to ENSO-neutral by late spring or early summer. The CPC noted, however, that the “exact timing of the transition is difficult to predict.” On Jan. 19, the Australian Bureau of Meteorology maintained its tracker at official El Niño status, with the event likely having peaked and ocean temperatures showing signs of gradual cooling. On Jan. 21, the International Research Institute for Climate and Society (IRI) and CPC forecasts indicated that all oceanic and atmospheric variables were indicative of a strong El Niño event, with consensus centering on strong El Niño conditions that will persist through spring 2016 (Fig. 3). The IRI/CPC briefing also indicated El Niño strength peaked in November–December, but that this was a “broad peak” with a gradual decline and the El Niño event would remain strong through late spring 2016. The North American multi-model ensemble currently shows a strong event extending into 2016 with gradual weakening heading into spring and summer (Fig. 4).

 

So what does this mean for the region? Even though forecasts are looking at the eventual decline of the El Niño signals, we are in the middle of a strong El Niño event. For the Southwest, the current seasonal forecasts and past events suggest we should see well above-average cumulative precipitation totals throughout our cool season (October–March), but we should also expect periods of inactivity between storms. Even though the 2015–2016 El Niño event “peaked” in November-December, we see impacts in the Southwest as they lag behind this spike in intensity, which means that we look to late winter and early spring as the most likely times to see increased storm activity associated with the El Niño signal. This doesn’t mean we can’t or won’t see increased activity outside of this window, but the default state for the desert Southwest is dry; even a strong El Niño event can only alter that system so much. We won’t be able to fully dissect and judge the 2015–2016 El Niño event until we see just how much rain and snow fell over the entire cool season. Given what we know about past events, our best bets for receiving above-average precipitation will be in February and March, or even April.  


Looking at the 1997–1998 event—the strongest El Niño event on record—most of Arizona and New Mexico received below-average rain and snowfall for all of January before returning to normal or above-normal precipitation in February and March (Figs. 5–8).

Southwest Climate Outlook January 2016

Thursday, January 21, 2016

In this Issue:


Precipitation: Over the past 30 days, the cumulative precipitation totals for Arizona and New Mexico were a mix of above- and below-average values (Fig. 1). Thirty-day averages often span wet and dry periods, while the week-to-week totals show considerably more variability. For example, precipitation totals in southern Arizona were buoyed by a series of storms that brought significant rainfall to the southwestern U.S. in the first week of January, which was preceded by a relatively below-average December and followed by an extended dry period in mid-January (see El Niño Tracker for more commentary and discussion of recent precipitation trends).

Temperature: December cooled off in much of the Southwest. Most of Arizona recorded normal to below-normal temperatures, while New Mexico was mostly normal to above normal, especially along the eastern half of the state (Fig. 2). Globally, 2015 was the warmest year on record and was among the top five warmest years for many western states (Fig. 3), and was the second warmest year on record for the U.S. overall.

Snowpack and Water Supply: Relatively frequent winter storm activity has brought impressive snowpack levels and snow water equivalent (SWE) percent of normal values to much of the western U.S., including above-normal values across almost all of the basins in Arizona and New Mexico (Fig. 4). Increased winter precipitation is an expected pattern given the current strong El Niño event. Later this spring, we will have a more accurate understanding of El Niño’s contribution to winter precipitation and a better sense of how temperature affected patterns of rain and snow and the contributions to water supply (See reservoir totals).

Drought: Long-term drought conditions persist across much of central and eastern Arizona along with the western edge of central New Mexico (Fig. 5). Recent runs of average to above-average precipitation have helped mitigate some of the short-term drought conditions, but we are continually reminded that multi-year droughts, such as those we experienced during much of the 21st century, will require multi-year periods to fully recover. El Niño offers hope for additional drought relief, particularly if above-average precipitation over the winter helps saturate soils and build snowpack in the region, boosting reservoir storage during springtime snowmelt runoff events.

El Niño Tracker: We are in the middle of a strong El Niño event forecast to remain in place through Spring 2016. We can expect variable weather throughout the winter season, but we anticipate more winter precipitation events and a higher cumulative total at the end of the cool season (see El Niño Tracker).

Precipitation & Temperature Forecast: The January 21 NOAA-Climate Prediction Center three month seasonal outlook predicts above-average precipitation for most of the Southwest this winter, with progressively increasing chances of above-average precipitation as you move south (Fig. 6, top). Temperature forecasts are split, with elevated chances for above-average temperatures along the West Coast and the Pacific Northwest, and increased chances for below-average temperatures centered over Texas and and southeastern New Mexico (Fig. 6, bottom).

Ask an Applied Climatologist - Q&A - How did observed weather correspond to (El Niño) climate predictions?

Tuesday, January 12, 2016

Looking back at Oct-Dec; Did observed weather events correspond with expected (El Niño) climate patterns?

January has kicked off with a bang, and the much anticipated super-mega-Godzilla El Nino is upon us.  El Niño conditions have been in place for months (Figure 1: Oceanic Niño Index), but has this El Niño event been impacting the weather of the Southwest in ways that are expected? Sort of, but not exactly.

This is probably to be expected, as we and others have been saying, no two El Niño events are alike (which means they are hard to compare), AND the October-November-December time period is still very early season for El Niño in the Southwest, so it would be premature to judge it too harshly, or to call this as having gone off the rails.

First off, the October through December time frame is a period of transition for the Southwest where we move from our summer monsoon thunderstorm season into a more westerly upper level circulation pattern and look expectantly for winter storms to bring precipitation to the region. October is also the time where a tropical storm can either directly or indirectly bring a boatload of moisture that can bring heavy precipitation to the region. Even during a ‘normal’ year with no El Niño influence, it is a ‘noisy’ time with lots of moving parts and potential variability, with quite a few dry and wet extremes in the historical record.  Long story short, El Niño or not, we expect to see a lot of variability during this transition season, so the larger question is how much does El Niño typically impact this season?

The influence of El Nino during this Oct-Dec transition operates through the mechanisms of tropical storm activity and early winter storm tracks, both of which can impact precipitation patterns across the Southwest. Typically, tropical storm activity is enhanced in the east Pacific during strong El Niño events, raising the likelihood of above-average precipitation from these events.  And the southward shift in the winter storm track, which is a hallmark impact of El Niño events, can set up as early as November. Based on this, we did largely expect this period to be wetter than average for Arizona and New Mexico and it mostly was (Figure 2: Departure from Normal Precip Oct-Dec 2015). But when we look a bit more closely, how we got this precipitation was a bit unusual, and it really didn’t fit the typical El Niño driven patterns.

For example, in October a series of cut off low pressure systems wandered across the Southwest (at one point, the same cut off low visited Arizona twice) picking up abundant tropical moisture to the south and creating widespread precipitation events across Arizona and New Mexico. These cut-off lows formed off a very busy jet stream pattern across the Pacific Ocean that in part was energized by all of the tropical storm activity across the basin (see the NOAA discussion here). Instead of directly interacting with tropical storms in the east Pacific, El Niño appears to have brought us to above-average precipitation for October in a much more complicated way (Figure 3: Departure from Normal Precip Oct 2015).

A highly amplified jet stream pattern continued into November, again partially driven by tropical storm activity being absorbed into the jet stream in the west Pacific (see NOAA synoptic discussion), leaving the Southwest to contend with a busy weather pattern but very little to work with in the way of moisture. A parade of storms marched through the Southwest through the month, but originated in the Gulf of Alaska and brought very little moisture with them. Some higher elevation and more northern areas were able to squeak out some precipitation with these storm systems, but overall the month was cool and relatively dry for the Southwest (Figure 4: Departure from Normal Precipitation Nov 2015). This was in contrast to the expectation of a much stronger subtropical jet (which was present, but south of AZ and NM) pulling in abundant moisture from lower latitudes.

December was largely characterized the by same pattern with the Southwest seeing passing storms and cooler than average temperatures, but little in the way of precipitation (Figure 5: Departure from Normal Precipitation Dec 2015). New Mexico was able to buck this trend a bit late in the month as a historic blizzard (compared to a similar snowstorm that hit the region in January of 1983, also a strong El Niño winter) swept through the area. 

The final precipitation totals for Oct-Dec 2015 across the Southwest are more or less what you would expect (generally above-average precipitation across New Mexico and northern AZ) for an El Niño year and a bit of the unexpected (drier-than average conditions across parts of western Arizona). But again, maybe that is what we should expect. Two other strong El Niño events (1983, 1997) are depicted for the same time period and are very different from each other. Oct-Dec 2015 establishes itself as yet another flavor of potential precipitation impacts during the fall season across the Southwest U.S.

El Niño Tracker - Dec 2015

Friday, December 18, 2015

El Niño conditions continued for a 10th straight month, and models continue to forecast a strong El Niño event that will last through spring 2016 and remain strong through the early part of the year. Forecasts focused on the persistence of sea surface temperature (SST) anomalies (Figs. 1–2) and weakened trade winds, enhanced convective activity in the central and eastern Pacific, and El Niño-related ocean-atmosphere coupling. Notably, the SST values in the Niño 3.4 region were at or above the record values in November. Climate scientists have been quick to point out that numerous factors contribute to the overall strength of El Niño, but we are certainly seeing one of the strongest events on record.

Image Source - Australian Bureau of Meteorology

Image Source - NOAA/NWS - Climate Prediction Center

On Dec. 8, the Australian Bureau of Meteorology maintained its tracker at official El Niño status, with the event having likely reached its peak. On Dec. 10, the Japan Meteorological Agency identified ongoing El Niño conditions as having reached their “mature stage” in the equatorial Pacific and “remarkably above-normal” SST anomalies and atmospheric convective activity. The agency projected that El Niño would remain in place through spring 2016 before transitioning to ENSO-neutral by summer. Also on Dec. 10, the NOAA-Climate Prediction Center (CPC) extended its El Niño advisory and identified the current atmospheric and oceanic anomalies as reflecting a strong El Niño event that will be one of the three strongest events on record. CPC models indicate the El Niño event will persist through winter, with a transition to ENSO-neutral conditions by late spring or early summer. On Dec. 17, the International Research Institute for Climate and Society (IRI) and CPC forecasts indicated that all oceanic and atmospheric variables were indicative of a strong El Niño event, with consensus centering on strong El Niño conditions that will persist through spring 2016 (Fig. 3).   The North American multi-model ensemble currently shows a strong event extending into 2016 with gradual weakening heading into spring (Fig. 4).

Image Source - International Research Institute for Climate & Society

Image Source - NOAA/NWS - Climate Prediction Center

So what does this mean for the region? Seasonal forecasts and past events suggest we should see well above-average cumulative precipitation totals throughout our cool season, but we should also expect periods of inactivity between storms. Past events also suggest the best bets for seeing above-average precipitation will be in February and March, and perhaps later in January. Looking at the 1997–1998 event—the strongest El Niño event on record—most of Arizona and New Mexico received above-average precipitation in December but below-average rain and snowfall for all of January before returning to normal or above-normal precipitation in February and March (Figs. 5–8). At this point, we know a strong El Niño event is underway, and it will likely have a number of projected impacts on the Southwest (and the world), but we will need to wait until seasonal totals are in to accurately gauge the impact of El Niño.

Image Source - Western Regional Climate Center - WestWide Drought Tracker

Image Source - Western Regional Climate Center - WestWide Drought Tracker

Image Source - Western Regional Climate Center - WestWide Drought Tracker

Image Source - Western Regional Climate Center - WestWide Drought Tracker


To provide data and analysis regarding possible impacts of El Niño on the Southwest, CLIMAS created an El Niño hub: climas.arizona.edu/sw-climate/el-niño-southern-oscillation

Please contact Dan Ferguson or Ben McMahan for more information

2015 - Eastern Pacific Tropical Storm Recap

Friday, December 18, 2015

The 2015 eastern Pacific tropical storm season was one of the most active seasons on record, with 18 named storms and 13 hurricanes, nine of which reached “major” hurricane status (category 3 or greater). We also saw the strongest hurricane on record, Patricia, in the eastern Pacific in late October, and the latest-forming major hurricane on record, Sandra, in late November (see NOAA’s National Hurricane Center for more details). This meets or exceeds the high end of the NOAA-Climate Prediction Center (CPC) seasonal forecast (from May 27), which predicted 15 to 22 named storms, seven to 12 hurricanes, and five to eight major hurricanes. The eastern Pacific hurricane forecast was tied to the ongoing El Niño forecast discussion, as conditions linked to El Niño (e.g., decreased wind shear in the tropical Pacific) also favored increased hurricane frequency and intensity in the Pacific region. Conversely, the Atlantic hurricane season was relatively quiet, with 11 named storms, four of which became hurricanes, including two major ones. This was mostly in line with NOAA-CPC projections of six to 10 named storms, one to four hurricanes, and up to one major hurricane. 

The season started off early and strong with two major hurricanes, Andres and Blanca, forming before June 1—Blanca brought considerable moisture into the Southwest—and Hurricane Carlos forming in early June. This start ran counter to the expected early season pattern in which hurricanes remain in the Pacific Ocean and generally head west. Few storms made direct landfall as hurricanes, but numerous systems made their presence felt by driving significant moisture into the Southwest, making substantial contributions to monthly seasonal precipitation totals. The season also was characterized by some relatively anomalous events, in particular, the record-breaking Patricia, which formed very quickly off the coast of Mexico before charging ashore in late October, and the late-forming Sandra. It remains difficult to provide direct attribution of El Niño as the primary cause of specific tropical storm events, but this elevated tropical storm activity and intensity are exactly the sort of patterns that we expect, given the influence that El Niño conditions were forecast to have on the eastern Pacific tropical storm season.

El Niño and Media Coverage in the Southwest

Friday, December 18, 2015

What do wildflowers, hantavirus, downhill skiing, locusts, and floods all have in common? The answer is El Niño in the Southwest. These subjects represent a small sample of media stories written during the last 33 years that connect regional impacts to the El Niño phase of the El Niño-Southern Oscillation (ENSO) and help illustrate an evolution in our understanding of the significance of El Niño to the region. 

El Niño was documented as early as the 19th century by sailors who noticed that in some years, often around Christmas, a warm ocean current off the coast of Peru would bring changes to the regional marine ecosystem. But modern media coverage didn’t begin until the 1982–83 El Niño event. This event was particularly strong, and many scientists took note, enticed by the possibility of associating regional climate patterns with ENSO, as this development held the key to future climate forecasting. 

Upon reviewing all newspaper articles that reference El Niño impacts in the Southwest, three different phases of scientific coverage emerge. During the first phase, from the early 1980s through 1996, the science of ENSO was still fairly new and most stories discussed the general global, national, and sometimes regional impacts of El Niño. The second phase began during the strong 1997–98 El Niño event. The number of articles about El Niño in the region drastically increased at this time and referenced regional impacts as they were happening or a few months later. During the third phase, 1999–2014, journalists tried to use El Niño as a tool to predict future impacts that might occur in the Southwest. 

Phase #1 – Early ENSO Science and Impacts: The first phase was characterized by a handful of articles that were general in scope and discussed the dynamics of the ENSO cycle. For the Southwest, floods and above-average precipitation usually made the news. As this phase progressed, growing scientific evidence allowed for greater attribution of regional impacts in the region to El Niño, and the media slowly started to cover the story. The first news article was written in June 1983. It discussed regional flooding patterns across the U.S. and described the large snowpack on the verge of melting in the Southwest[1].  During this first phase, ENSO became a recognized phenomenon and the general idea that El Niño brought cooler, wetter weather to the region became fairly well established. However, many of the impacts attributed to El Niño were underdeveloped (e.g., killer bees migrating from Arizona to California[2] and the appearance of bubonic plague in New Mexico[3]) This was still early on in our understanding of the predictability of El Niño itself and many news articles grappled with how to cover long-range forecasting. 

Phase #2 – Attribution of El Niño Impacts in the Southwest: The second phase began during the very strong 1997–98 El Niño event. A substantial increase in media coverage occurred then, compared to prior events, with more than 100 news articles referencing impacts in the Southwest. By this point, researchers better understood the science of El Niño and its regional impacts. This meant increased attribution of weather and climate events to the ENSO cycle in the media, starting with coverage of Hurricane Nora, which “deposited two years’ worth of rain on the small town of Yuma”[4] in fall 1997. El Niño stories that winter discussed huge storms that dumped heaps of snow on ski slopes in Taos, New Mexico[5], but also buried sheep and cattle near Roswell[6], and brought heavy rain to Arizona in February and March[7]. This above-average precipitation promoted vegetation growth across the Southwest, translating into high pollen counts[8] and brightly blooming wildflower patches in Arizona[9]. The healthy desert vegetation also brought droves of locusts to western Arizona in the spring of 1998[10]  and boosted deer mice populations, which led to several occurrences of hantavirus in humans in the Four Corners region[11]. Media attention shifted in tone as the 1997–98 El Niño event progressed. Over time, a popular sentiment developed: “Oh, just blame it all on El Niño.”[12] Stories focused on the negative impacts of El Niño, and it often became a scapegoat for everything from the San Francisco Giants not getting enough practice time during spring training[13] to increases in food prices[14].

Phase #3 – The Media Race to Predict the Next El Niño: The strong 1997–98 El Niño generated a lot of scientific and media interest in predicting the next event. The third phase of media coverage was characterized by an effort to stay ahead of the curve and be the first to prepare the region for the impacts of another El Niño. This phase characterizes a time when scientists and journalists were still learning about the different flavors of each El Niño. Some were weak (2004–05) or moderate (2002–03), some quickly fizzled out (2006–07), and some were predicted but never actually started (2014). Each of these different events influenced regional weather patterns in distinct ways and climate information providers weren’t always able to clearly communicate the nuances to the media. Many news articles talked up the potential impacts of El Niño leading up to events (e.g., “Out and about: Dreaming of a white Christmas”[15]) only to carry disappointed headlines a few months later (e.g., El Niño rain turns out to be El Floppo”[16]).

It seems that we are currently beginning a new phase of El Niño media coverage with the 2015–16 event. Scientists have an improved understanding of the range of El Niño impacts and can better attribute certain weather events and occurrences to the ENSO cycle. In addition, this information has been translated into local news sources. While some national media outlets and climatologists have portrayed the 2015-16 El Niño as Godzilla[17], not one article referencing Arizona or New Mexico has characterized it as a monster. Perhaps that’s because El Niño means a lot of positive things for the region. Despite potential hazards, the desert could use some cooler, wetter weather, especially in contrast to the multi-year droughts that have characterized much of the 21st century thus far. But possibly it’s also because on a regional level, scientists and the media are better understanding and representing what El Niño means for the Southwest.


  1. “Summer floods seen as threat to much of nation.” The Washington Post. June 3, 1983.
  2. “Environment watch.” The Age. October 25, 1993.
  3. “And now for the weather: Two years from today there will be rain.” The Times. March 6, 1996.
  4. “International news: El Niño pours could water on LA routine.” The Guardian. September 27, 1997.
  5. “El Niño smiles on ski resort.” St. Louis Post-Dispatch. December 14, 1997.
  6. “El Niño gets the blame for weirdness.” USA Today. January 8, 1998.
  7. “It moved like a conveyor belt, hit like a train.” The Ottawa Citizen. January 15, 1998.
  8. “El Niño triggers sneezing season, pollen gets kicked up early.” USA Today. February 23, 1998.
  9. “El Niño’s good side: Wildflowers.” The New York Times. March 30, 1998.
  10. “Earthweek: Diary of a Planet.” The Toronto Star. April 25, 1998.
  11. “Lethal virus borne by mice makes return in West.” The New York Times. June 25, 1998.
  12. “Oh, just blame it all on El Niño.” Calgary Herald. July 13, 1998.
  13. “Giants expect wealth, stadium raises Magowan’s hopes.” San Jose Mercury News. February 22, 1998.
  14. “El Niño boosts produce prices.” The Toronto Star. April 22, 1998.
  15. “Out and about: Dreaming of a white Christmas.” The Santa Fe New Mexican. November 30, 2006.
  16. “El Niño rain turns out to be El Floppo.” East Valley Tribune. February 23, 2007.
  17. “Latest forecast suggests ‘Godzilla El Niño’ may be coming to California.” Los Angeles Times. December 15, 2015.

Southwest Climate Outlook December 2015

Thursday, December 17, 2015

Precipitation: Over the past 30 days, Arizona recorded mostly below-average precipitation, while most of New Mexico received normal to above-average precipitation (Fig. 1). This short term variability is typical in the seasonal transition, but looking more generally over the last three months we see a consistent pattern, and one with the fingerprints of El Niño all over it (primarily via enhanced tropical storm activity): both Arizona and New Mexico recorded top 20 precipitation totals for September through November (Fig. 2). 

Image Source - Advanced Hydrologic Prediction Service

Image Source - NOAA - National Centers for Environmental Information

Temperature: November was cooler than average in most of Arizona but average to above-average across most of New Mexico (Fig. 3), a pattern which has persisted over the past 30 days. This cool down is relatively recent; the last three months (September through November) were record warm for New Mexico and near-record warm for Arizona. Year-to-date (January through November) temperatures are among the top five warmest for both Arizona and New Mexico.  

Image Source - High Plains Regional Climate Center

Snowpack & Water Supply: We are early in the snow season, and while some early storms brought impressive snow totals to portions of the west for this time of year, snow water equivalent (SWE) percent of average reflects the variability we might expect at this point in the season (Fig. 4). We will have a much better picture of El Niño’s contribution to winter precipitation looking back later this spring than we do looking forward, and we will have a better sense of how temperature affected patterns of rain and snow and the contributions to water supply (See reservoir totals).

Image Source - Western Regional Climate Center

Drought: Long-term drought conditions persist across nearly all of Arizona and portions of northwestern New Mexico (Fig. 5). Average to above-average 2015 precipitation has helped mitigate some of the short-term drought conditions, but multi-year droughts, which we have experienced for much of the 21st century, will require multi-year periods to fully recover. The ongoing El Niño event offers hope for additional drought relief. Above-average precipitation over the winter helps saturate soils and build snowpack in the region, which could lead to higher reservoir storage during springtime snowmelt runoff events.

Image Source - U.S. Drought Monitori

Tropical Storm Activity: In a normal year, we would have nothing to say about tropical storms in mid-December, but a few late season storms, including major Hurricane Sandra, popped up in late November, long after the typical season. This capped an eastern Pacific tropical storm season that shattered existing records and almost certainly was associated with the current strong El Niño event (see recap of tropical storm season). 

Precipitation & Temperature Forecast: The December 17 NOAA-Climate Prediction Center seasonal outlook predicts above-average precipitation for most of the Southwest this winter, with progressively increasing chances of above-average precipitation to the south (Fig. 6, top). Temperature forecasts are split, with elevated chances for above-average temperatures along the West Coast and increased chances for below-average temperatures centered over Texas and extending across most of southeastern New Mexico (Fig. 6, bottom).

Image Source - NOAA/NWS - Climate Prediction Center


In this Issue:

El Niño and Vector Borne Disease - What do we know about mosquitos, disease, and climate?

Monday, December 14, 2015

We are usually able to enjoy the patio by October, but the mosquitoes were still biting. What does the science tell us about El Niño and mosquito-borne disease? Short answer: it’s complicated. 

With respect to mosquito-borne disease, we tend to think about a mosquito season; the period of the year during which mosquitoes are active. For diseases like West Nile virus, the cycle starts when mosquitoes bite birds, infecting them with the disease. Eventually, often in late summer and early fall, enough mosquitoes and birds are infected that the disease spills over into human and horse populations. This requires that there are enough infected mosquitoes and that these mosquitoes survive long enough to become infectious and bite humans or horses. 

That gets us back to the mosquito-season. Immature mosquitoes—egg, larval, and pupal stages—require water to compete their life cycle. This water is provided both by precipitation and by human behavior, collecting in green pools, unprotected water storage, clogged gutters, or saucers under plants. Temperature drives how quickly an immature mosquito becomes an adult; typically, warmer temperatures speed up development. Another important piece is adult mosquito survival and host-seeking activity, both of which are mediated by humidity. Thus, the duration and intensity of any year’s mosquito season is going to be strongly influenced by temperature and precipitation. 

This year, with respect to precipitation, we had a wet June but then a normal July–September rainfall. The rains are expected to remain above-average through the winter. Despite the mosquitoes we experienced this summer and fall, the implications of the summer lull in precipitation are unknown. Because of the ramping up of West Nile virus in the bird-mosquito cycle, we might actually escape a bad year and hopefully, the bird-mosquito transmission cycle was broken and won’t have enough time (enter the effect of cooler winter temperatures) for it to build up again and spill over to humans. 

Research results are mixed, being highly dependent on the disease of concern and the region of study. Intuitively we know there must be an association between climate and vector life cycles, as the life cycle of invertebrates are often tightly associated with weather. However, with urban mosquitoes like the Culex species that transmit West Nile in the United States and the Aedes species that transmit dengue and chikungunya, human behavior plays a role in mediating exposure to mosquitoes, the availability of breeding sites, and even mosquito survival. Moreover, the diseases themselves have an intrinsic intra-annual cycle in which the proportion of a given population that is susceptible to infection fluctuates between years, confounding the climate-driven associations with temperature and precipitation. 

That leaves us with a dissatisfying ‘we don’t know’ and ‘it all depends.’ Our experience will depend on the previous years’ mosquito abundance, previous years’ human or other host disease occurrence, current human or other host susceptibility, and the duration of the anomalous weather. It does leave us with a positive message, though: what we do as individuals does matter. Protect yourself from mosquitoes, empty breeding sites, cover your water storage, repair your window screens, and use mosquito repellent when you go out of doors. 

Bhuwan Thapa - CLIMAS Climate & Society Fellow

Tuesday, November 17, 2015

Bhuwan Thapa is a 2015 CLIMAS Climate & Society Graduate Fellow. He and the other graduate fellows (C. Greene, E. Magrane, & V. Rountree) will present the results of their fellowship work on Friday Nov 20, at 10:30 a.m., in ENR2, Room 604.


Figure1: Community members in Tupche VDC, Nuwakot celebrating Rice Plantation Day within two months of the earthquake event (Source: B. Thapa, June 30, 2015)


How farmers are responding to Gorkha Earthquake, climatic and socioeconomic changes in Nepal

Following the Gorkha earthquake in April 2015, many able farmers in the hard-hit Nuwakot district came together and repaired the damaged irrigational canals. They contributed labor and financial resources and where necessary procured additional funding from government institutions. Though some systems could not be repaired immediately due to lack of human and financial resources, the farmers demonstrated the power of collective action in responding to national disasters.

One of the uniqueness of Nepalese irrigation system is the farmer-managed irrigation system where farmers take the responsibility of the overall irrigation management including operation and maintenance. Indeed during the field trip of summer 2015, I learned that these institutions were pivotal in responding to multiple stresses resulting from natural disasters, climatic and socioeconomic changes.

Over the years, stresses on agriculture and water management have materialized in various ways. The monsoon has become erratic causing unpredictable rainfall with variable timing and intensity. The crops are infected with new diseases due to agricultural practices and warmer temperature. The increase in labor price due to massive labor outmigration in Arab countries and high fertilizers price have made some crop varieties economically unviable. These changes have serious implications on irrigated agricultural productivity and wellbeing of thousands of farmers subsiding on agriculture.

In response, the farmers have addressed these challenges through different strategies. In order to supply additional water during shortages, they have installed water pumps to lift river water to up to 50 feet high and distribute through existing irrigation distribution system. In areas where augmenting additional water is not an option, farmers have switched to less water demanding crops. Most of the farmers now use hybrid varieties that produce high yield for less water.

These diverse interventions implemented by farmers have provided me with valuable insights on on-the-ground climate change adaptation.  When provided with right incentives and resources, farmers have demonstrated effective adaptive responses through structural and non-structural interventions. Some of the structural interventions included adoption of technology and hybrid seed varieties whereas non-structural interventions were the modifications of water management rules and changes in agricultural practices based on local knowledge. I have learned that the local level institutions with decentralized decision making can be the platform for adaptive responses. These institutions can be crucial for resiliency of irrigated agriculture because they empower the farmers and strengthen their capacity for timely response during crisis.

I have immensely benefited from knowledge-coproduction model that I applied in this research. I incorporated farmers’ group as the valuable partner with repository of local knowledge on adaptive responses. They shed light on multi-faceted dimensions of climate change and provided feedback on my findings which helped me align my research questions on the areas that are more relevant to them.


The research was conducted during summer of 2015 with support from CLIMAS fellowship and ICIMOD HI-AWARE project. Comprehensive study on climate resilient irrigated agriculture in Gandaki River Basin in Western Nepal will be conducted as a part of my PhD research funded by ICIMOD HI-AWARE project.

Eric Magrane - CLIMAS Climate & Society Fellow

Monday, November 16, 2015

Eric Magrane is a 2015 CLIMAS Climate & Society Graduate Fellow.  He and the other graduate fellows (C. Greene, V. Rountree, & B. Thapa) will present the results of their fellowship work on Friday Nov 20, at 10:30 a.m., in ENR2, Room 604.


Climate Change and Poetry

At the September 2014 United Nations Climate Summit in New York, Kathy Jetnil-Kijiner, a poet from the Marshall Islands, performed a poem dedicated to her young daughter. The poem speaks of hope for the future in the midst of sea level rise for a homeland—standing just two meters above sea level—that is on the frontlines of climate change: 

no one’s drowning, baby
no one’s moving
no one’s losing
their homeland
no one’s gonna become
a climate change refugee

or should i say
no one else


As both a poet and a geographer, I think a lot about the work that poems like this do. Can poets and artists help us find ways forward in a changing world?

From planned arts events at the upcoming international climate conference in Paris to ongoing poetry forums in response to tragedies such as the gulf oil disaster—as just two examples—poets and artists are engaging in a vibrant and diverse response to climate change.

The poetic response to climate change will be the topic of an upcoming community course that I’m teaching for the University of Arizona Poetry Center this fall. In the course, we’ll read poetry and think about climate change. We’ll discuss how poems may reflect or complicate different ways of understanding the issue.  As I wrote in the course description, by blending readings of poetry with social and scientific readings of climate change, we’ll learn more about environmental poetry and about climate change, and we’ll think about how poetry and creativity may have a role in adapting to a warming world.

There is not one climate change; rather, there are many climate changes. This refers to both the physical science—the awareness that different regions will see different effects—as well as to the social perception of climate change. Alternate frames place it, for example, as an environmental justice issue, a national and global security issue, or an opportunity for social change. As recent provocative books and no less than the Pope have pointed out, climate change calls capitalism itself into question.

I believe that poems can help us to perceive these different frames of climate change in fresh and imaginative ways. Much like CLIMAS is a “boundary organization,” one that helps to bring together researchers with decision makers around climate change and its impacts in the southwest, poems can be “boundary objects” that help illuminate the issue. I think about the ending of my own poem, “Mesquite,” which imagines what the deep taproot of a mesquite tree might have to say to a room full of humans:

And I say, I will be ready
if the drought comes.

And I say, go deep
into the Earth.

And I say, go deep
into yourself, go deep
and be ready.

As climate change is projected to bring increased drought and wildfires to the southwest, the poem is a way into thinking about adaptation and resilience. In fact, I’m imagining the Climate Change & Poetry course itself in a similar way: as adaptive practice and experimentation in both communicating and re-imagining the ways that we approach climate change.

The Climate Change & Poetry course at the University of Arizona Poetry Center began on September 28 and continued through November 9. Sixty percent of course fees will be donated to Watershed Management Group, a local environmental nonprofit.


Eric Magrane is a 2015 CLIMAS Climate & Society Graduate Fellow, a Ph.D. candidate in the School of Geography & Development, and Graduate Research Associate in the Institute of the Environment.

His poem “Mesquite” will be in The Sonoran Desert: A Literary Field Guide, forthcoming from The University of Arizona Press. See the full poem here.

Southwest Climate Outlook September 2015

Thursday, September 17, 2015

Precipitation:  In the past 30 days, much of Arizona and New Mexico recorded below-average precipitation, although isolated areas received above-average precipitation (Fig. 1). This is consistent with the variable nature of the monsoon, especially during the seasonal transition. Water year precipitation to date (since Oct 1, 2014) offers hope in terms of drought relief, with much of Arizona and New Mexico recording above-average precipitation for the water year (Fig. 2).

Temperature: Temperature anomalies in the past 30 days were between 0 and 6 degrees F above average across most of Arizona and New Mexico (Fig. 3). Despite similarly near-record warm temperatures so far in 2015, temperatures have not felt as hot as they did last year, with above-average humidity suppressing daytime high temperatures and boosting nighttime lows. Arizona recorded near-record high statewide average temperatures from January to August 2015, while average temperatures in New Mexico for the same time period were among the state’s top 10 warmest (Fig. 4). Extremely hot days have been rare, with fewer than average very hot days across the region.

Monsoon: Variable spatial coverage and intensity along with intermittent frequency of precipitation events makes it difficult to characterize any monsoon as “normal.” That said, 2015 has been fairly typical for monsoon precipitation; the storms have been variable, most locations saw regular precipitation events that brought their total precipitation close to long-term averages, and, unlike last year, fewer locations recorded high-intensity precipitation events that dropped a full season or years’ worth of precipitation in a single storm event (see Monsoon Tracker on pgs. 6-7 for details).

Tropical Storm Activity: During late summer and into fall, tropical storms in the eastern Pacific Ocean have a better chance to recurve back into the Southwest, rather than heading west across the Pacific Ocean. Record sea surface temperatures intensify these storms, upping the chance that an organized system will bring moisture (humidity) and precipitation to the Southwest. Despite regular incursions of tropical moisture, we have not seen many heavy precipitation events associated with tropical storms, as we did with Norbert and Odile in 2014, save for recent extreme flooding in northern Arizona and Utah. However, we are just past the midway point of the tropical storm season, leaving time for tropical storm systems to bring additional (possibly heavy) rainfall to the region.

Drought & Water Supply: The U.S. Drought Monitor identifies persistent multi-year drought across the West. Arizona and New Mexico are grappling with years of accumulated drought and water deficits, but water year precipitation has helped scale back drought conditions, particularly in New Mexico (see Reservoir Volumes on pg. 8 for details).

Precipitation & Temperature Forecasts: The Sept. 17 NOAA-Climate Prediction Center seasonal outlook predicts above-average precipitation for most of the Southwest this fall (Fig. 5, top). Notable exceptions are northern California and most of the Northwest. Temperature forecasts are split, with elevated chances for above-average temperatures along the West Coast and into southwestern Arizona, and increased chances for below-average temperatures centered over Texas and extending across most of New Mexico (Fig. 5, bottom).

Monsoon Summary Jun 15-Aug 20

Friday, August 21, 2015

Originally published in the August 2015 CLIMAS Southwest Climate Outlook

The monsoon started off early and strong with several widespread thunderstorms in late June and early July, especially in Arizona, which recorded its second wettest June on record.  Precipitation tapered to some extent in July in Arizona but continued to be frequent and widespread in New Mexico, which recorded its 10th wettest July on record (Figs. 1a-2a).  

Overall monsoon activity has taken a break thus far in August, although a few powerful and localized storms brought significant precipitation to portions of Arizona. This pattern is a defining characteristic of the 2015 monsoon, particularly in Arizona, where many of the monsoon storms have been highly localized, dropping heavy precipitation in smaller areas and often on high elevation peaks instead of more widespread and systematic monsoon activity. Portions of southern Arizona and the Four Corners region—areas that saw considerable precipitation deficits in the past few years—have been the beneficiaries of this variable coverage, especially in the past few weeks. This pattern may change if the monsoon ridge sets up further east, allowing for more organized storm activity to flow in from the south in the coming weeks, or if later-season eastern Pacific tropical storm activity ramps up and helps drive moisture into the region. 

We also have seen some weakening of the monsoon ridge since July 5, likely due to El Niño convection picking back up, but it remains to be seen what the overall impact of El Niño will be on this year’s monsoon. Regional dewpoint readings also illustrate the variability of monsoon activity, particularly in July and into August (Fig. 2).

In the first two months of the monsoon, most of northern Arizona and nearly all of New Mexico recorded above-average precipitation (Figs. 3a–b), albeit with a wide range of precipitation totals across the region (Figs. 4a–b). Southwestern Arizona, particularly the southwest and northwest corners, are notable exceptions to this pattern, although these areas typically receive far less monsoon precipitation overall. The percent of days with rain highlights the regularity of monsoon precipitation thus far, with much of eastern Arizona and nearly all of New Mexico recording rain events (greater than 0.01 inch) on 35 to 50 percent of days since June 15 (Figs. 5a–b). The daily intensity index (Figs. 6a–b) further illustrates the steady nature of most of this monsoon precipitation; higher values indicate much of the rain fell in a single event and lower values indicate more frequent and less intense events.

August 2015 - CLIMAS Southwest Climate Outlook

Thursday, August 20, 2015

Precipitation: In the past 30 days, much of southern Arizona and New Mexico received below-average precipitation, with portions of northern Arizona and New Mexico recording above-average precipitation (Fig. 1). In August, below-average precipitation has been punctuated by a few intense storm systems, mostly in Arizona. For New Mexico, July was the 10th wettest month on record. In general, the precipitation events that have occurred have been more localized storm systems, resulting in highly variable precipitation across the region (see Monsoon Tracker, pages 5-6).

Image Source - High Plains Regional Climate Center

Temperature: After a record warm start to 2015, much of the Southwest cooled off in July, especially in Arizona (Fig. 2). This respite was short-lived however, as temperature anomalies in the past 30 days were between 0 and 6 degrees F above normal across most of New Mexico and most of Arizona (Fig. 3). Globally, 2015 likely will challenge 2014 for warmest year on record, a trend that could affect temperature trends in the Southwest.

Image Source - High Plains Regional Climate Center

Monsoon: The highly variable nature of the monsoon in terms of when and where rain falls poses a serious challenge to anyone attempting to characterize the monsoon. That said, summer 2015 has been relatively typical, with average to above-average rainfall across much of Arizona and more consistent and sustained above-average precipitation in New Mexico. We also have seen expected breaks in storm activity as the monsoon ridge moves, affecting regional patterns of precipitation—or lack thereof—across the region (see Monsoon Tracker, pages 5–6 for a more detailed discussion).

Drought & Water Supply: The U.S. Drought Monitor continues to emphasize drought conditions across the West, with particularly severe conditions in California and Nevada (Fig. 4). Arizona and New Mexico continue to grapple with years of accumulated drought and water deficits, but recent sustained and widespread precipitation has helped slightly scale back drought conditions, particularly in New Mexico (see Reservoir Volumes, page 7).

Wildfire: As of July 31, wildland fires had burned approximately 120,000 acres in Arizona and about 40,000 acres in New Mexico. One notable blaze was the Finger Rock fire, which ignited in the Santa Catalina Mountains in southern Arizona and was visible from Tucson for a number of days. Favorable weather conditions allowed fire managers to let the fire burn out naturally, despite proximity to residential areas. This fire season, well above-average precipitation in Arizona in June and in New Mexico in July tamped down fire risk across the region, resulting in limited regional fire and fire suppression activity, and favorable weather conditions permitted a number of fires to be left to burn, benefitting forest health. 

Precipitation & Temperature Forecasts: The Aug. 20 NOAA-Climate Prediction Center seasonal outlook predicts above-average precipitation for most of the Southwest and Intermountain West this summer (Fig. 5, top). Notable exceptions are northern California and far northwestern Nevada. Temperature forecasts are split, with elevated chances for above-average temperatures along the West Coast and into western Arizona (and most of the western U.S.), and increased chances for below-average temperatures centered over Oklahoma and Texas and extending across New Mexico (Fig. 5, bottom). It remains to be seen what effect eastern Pacific tropical storms and El Niño will have on these patterns.

Image Source - NOAA/NWS - Climate Prediction Center


Also in this issue:

El Niño Tracker - July 2015

Monday, July 20, 2015

El Niño conditions continue for a fifth straight month, and at this point, forecasters are relatively bullish that we are witnessing the development of a moderate-to-strong event that could rival 1997 in absolute magnitude later this year. The most recent outlooks from various sources offer a consistent cluster of forecasts calling for a clear El Niño signal that is maintained or even strengthens well into early 2016. Forecasts focused on the persistence of sea-surface temperature (SST) anomalies (Figs.1 - 2) along with weakening trade winds, ongoing convective activity in the central and eastern Pacific, and El Niño-related ocean-atmosphere coupling.

On July 7, the Australian Bureau of Meteorology maintained its tracker at official “El Niño” status, identifying a strengthening El Niño (in part due to increased tropical storm activity), and projecting the event as likely to persist through the end of 2015 and into 2016. On July 10, the Japan Meteorological Agency identified strengthening El Niño conditions in the equatorial Pacific, and forecast that the current El Niño conditions were likely to last until winter. On July 9, the NOAA-Climate Prediction Center (CPC) extended its El Niño advisory with a greater than 90-percent chance that El Niño will continue through winter 2015-2016, and an 80-percent chance it will last into early spring 2016. It cited the increasingly positive SST anomalies in the central and eastern Pacific and ongoing ocean-atmospheric coupling and convection activity as indicators of an ongoing and strengthening event (Fig. 3). On July 16, the International Research Institute for Climate and Society (IRI) and CPC forecasts indicated continued strengthening of El Niño through 2015 and into 2016, with a moderate event likely becoming a strong event by summer or early fall and lasting into early 2016. The North American multi-model ensemble currently shows a moderate event extending through early summer, with potential for a strong event by mid-summer or early fall (Fig. 4).

It is clear that we are in the midst of an ongoing and strengthening El Niño event.  If this event remains on the current trajectory, it could surpass the strongest El Niño events of recent decades (1997 in particular), with implications for both Southwest and global communities. 

In May and early June, we witnessed exactly the sort of patterns we might expect to see in Arizona and New Mexico under El Niño conditions—above-average precipitation and below-average temperatures. If El Niño persists into winter 2015-2016, particularly if it remains a moderate-to-strong event, we would likely continue to see above-average precipitation in the Southwest (Fig. 5). Although the presence of El Niño conditions often has been associated with a delay in the start of the monsoon, this year the monsoon began early. However, a resurgent El Niño signal now may be pushing back and could work to disrupt the monsoon ridge, leading to one or more ‘breaks’ in the monsoon. The event could also lead to a repeat of 2014’s above-average eastern Pacific tropical storm season, when conditions favorable to El Niño were thought to be driving increased tropical storm activity in the Southwest in September and October.

Image Source - Australian Bureau of Meteorology

Image Source - National Climatic Data Center

Image Source - International Research Institute for Climate and Society

Image Source - NOAA - Climate Prediction Center

Image Source - NOAA Climate.gov

Monsoon Summary - (June 15 - July 16)

Thursday, July 16, 2015

After a few anomalous incursions of tropical moisture in early June, we saw an early beginning to the monsoon in mid- to late June, a few weeks ahead of the typical start date (Fig. 1). Regional dewpoint/humidity readings for June illustrate the multiple incursions of tropical moisture, followed by the onset of monsoon conditions later in the month (Fig. 2).

The monsoon ridge was able to set up early, leading to a number of precipitation events (including above-average precipitation) across the Southwest starting in the last week of June. As recently as last month, we had been anticipating a delayed start to the monsoon, as El Niño conditions tend to suppress its onset. However, the opposite occurred, possibly due to a record-strong Madden Julian Oscillation (MJO) pattern that temporarily suppressed El Niño’s typical influence on the subtropical ridge. We have seen some weakening of the monsoon ridge since July 5, likely due to El Niño convection picking back up, but it remains to be seen what the overall impact of El Niño will be on this year’s monsoon.

In the first month of the monsoon, most of New Mexico and much of eastern Arizona received well-above-average precipitation (Fig. 3a-b), albeit with a wide range of precipitation totals across the region (Fig. 4a-b). Western Arizona (particularly the southwest and northwest corners) are notable exceptions to this pattern, although these regions typically receive far less monsoon precipitation overall.  The percent of days with rain highlights the regularity of monsoon precipitation thus far, with much of eastern Arizona and most of New Mexico recording rain events (>0.01”) on 35-50 percent of days since Jun 15 (Fig. 5a-b). The daily intensity index (Fig. 6a-b) further illustrates the steady nature of most of this monsoon precipitation, where higher values indicate much of the rain fell in a single event and lower values indicate more frequent and less intense events.

June 2015 SW Climate Podcast - Tropical Storms, Monsoon, Wildfire & El Niño

Wednesday, July 1, 2015

In the June 2015 edition of the CLIMAS SW Climate Podcast, Mike Crimmins and Zack Guido recap the month of June, including the quick transition from cool and wet to hot and muggy conditions.  The discuss the impact of tropical storms on the region, the early start to this season, and what this may or may not mean in terms of relationship to monsoon patterns.  They turn to El Niño, and the impact the El Niño signal may be having on the region, both looking back at the past few months, but in particular looking forward at what this could mean for the southwest in terms of precipitation patterns over the next 12 months.

  • 0:00 Introduction
  • 1:15 June Recap- Temperature, Precipitation, Influence of Tropical Storms, etc.
  • 8:00 Links to the Monsoon - System is setting up - what we've seen so far, and what we can expect moving forward.
  • 15:00 Monsoon and (early arriving) tropical storms, and the impending El Niño event - how big of a role will ENSO play in the monsoon?  tropical storms?
  • 22:30 Looking back to the El Niño event of 97-98 - how does this one compare?  Could it be even bigger?  What would that mean for the Southwest?
  • 26:00 Looking towards the rest of summer, fall and winter - Given persistent El Niño- short term effects (temp & precip) vs. impact on long term trends (like drought).
  • 29:00 Wrapping up and looking forward.

Please note: we are aware of the intermittent audio glitches in the recording, and are working towards a solution.  They are brief and shouldn't interfere with the overall podcast, but we apologize for any inconvenience.

El Niño Tracker - June 2015

Friday, June 19, 2015

Originally Published in the June 2015 CLIMAS SW Climate Outlook (SWCO)


El Niño conditions continued for a fourth straight month with no signs of weakening or disorganizing. Forecasts focused on the persistence of sea-surface temperature (SST) anomalies (Figs.1 - 2) along with weakening trade winds, ongoing convective activity, and El Niño-related ocean-atmosphere coupling. Despite the high degree of uncertainty associated with forecasting El Niño this time of year (the so-called spring predictability barrier), the most recent outlooks from various sources offer a consistent cluster of forecasts calling for a clear El Niño signal that is maintained or even strengthening. 


Image Source - Australian Bureau of Meteorology


Image Source - National Climatic Data Center

On June 9, the Australian Bureau of Meteorology maintained its tracker at official “El Niño” status, identifying persistent SST anomalies, weak trade winds, and ocean-atmospheric coupling as indicators this El Niño event was strong enough to extend through 2015. On June 10, the Japan Meteorological Agency identified strengthening El Niño conditions in the equatorial Pacific, and forecast that the current El Niño conditions were likely to last until winter. On June 11, the NOAA-Climate Prediction Center (CPC) extended its El Niño advisory with a 90 percent chance that El Niño will continue through fall 2015 and an 85 percent chance the event would last through winter 2015-2016.  It pointed to the increasingly positive SST anomalies, along with ongoing ocean-atmospheric coupling and dateline convection activity, as indicators of an ongoing and strengthening El Niño event (Fig. 3). On June 18, the International Research Institute for Climate and Society (IRI) and CPC forecasts indicated continued strengthening of El Niño through 2015, with a moderate event during summer and likely stronger in the fall, lasting into early 2016. The North American multi-model ensemble currently shows a moderate event extending through early summer, with potential for a strong event by mid-summer or early fall (Fig. 4).


Image Source - International Research Institute for Climate and Society


Image Source - NOAA - Climate Prediction Center

Last year’s vacillating signals and forecasts may have led forecasters to take a more conservative approach when presented with similar conditions earlier this year to avoid repeating the “enthusiastic” forecasts of Spring 2014 that didn’t immediately pan out.  That said, we appear to be in the midst of an ongoing and strengthening El Niño event.  If this event remains on the current trajectory, it could rival our strongest El Niño events of recent memory (1997 in particular), with implications for both Southwest and global communities.

The recent above-average precipitation and below-average temperatures in Arizona and New Mexico are exactly the sort of patterns we expect to see under El Niño conditions. In the immediate future, we may see a return of some early season tropical storm activity, as we did with Hurricane Blanca in June. El Niño also points toward a possible delay in the start of the monsoon, which could actually extend the hotter and drier early portion of summer. We could also see a repeat of 2014’s above-average eastern Pacific tropical storm season, when conditions favorable to El Niño were thought to be driving increased late-season tropical storm activity in the Southwest.  And if El Niño persists into winter 2015-2016, particularly if it remains a moderate-to-strong event, we would likely see patterns of above-average precipitation in the Southwest (Fig. 5).


Image Source - NOAA Climate.gov

El Niño Models - May 2015 SW Climate Podcast

Friday, June 19, 2015

Excerpt from the May 2015 CLIMAS SW Climate Podcast


Image & Story Credits

Southwest Climate Outlook June 2015

Thursday, June 18, 2015

Originally Published in the June 2015 CLIMAS SW Climate Outlook (SWCO)


Precipitation: In the past 30 days, most of New Mexico and much of northern Arizona recorded well-above-average precipitation (Fig. 1).  Climatologically, we are in one of the drier times of year for the Southwest, so this precipitation and humidity (mostly tied to early season Pacific tropical storm activity) helped tamp down fire risk. This respite was short-term however, as water-year observations since October 1 reflect persistent and ongoing drought conditions, with most of the western U.S. recording well-below-average precipitation (Fig. 2).  Notable exceptions are New Mexico, Colorado, Wyoming, and Montana, but with most recent precipitation falling on the eastern side of the Continental Divide.


Image Source - NOAA/NWS - Advance Hydrologic Prediction Service


Image Source - NOAA/NWS - Advance Hydrologic Prediction Service

Temperature: Tropical storm activity led to unseasonably mild and pleasant conditions across the Southwest, with temperature anomalies across much of Arizona and New Mexico between 2 and 6 degrees below average during the past 30 days (Fig. 3).  But by mid-June, the Southwest had returned to more typical hotter and drier temperature and humidity patterns.  These conditions are likely to persist until the monsoon fires up, which may be delayed by El Niño conditions.  


Image Source - High Plains Regional Climate Center

Snowpack/Streamflow: At this point in the season (and after a relatively warm winter), snow is absent across much of the West. The recent unseasonably cool and wet conditions led to some anomalous snow water equivalent (SWE) readings in Colorado and Utah (Fig. 4), but it remains to be seen if this will have any long-term effects on water supply or streamflow.  Streamflow forecasts reflect generally warm and dry winter conditions, with below-average forecasts across most of the western U.S. (Fig. 5), save for a few locations that saw late-season spikes in storm activity.


Image Source - Natural Resources Conservation Service 

Drought & Water Supply: The U.S. Drought Monitor highlights drought conditions across the West, with particularly severe conditions in California and Nevada. Arizona and New Mexico are still grappling with the impacts of years of accumulated drought, and the monitor emphasizes long-term drought conditions across Arizona and western New Mexico.

Wildfire: Mild spring weather, above-average precipitation and above-average relative humidity have reduced wildfire risk in Arizona and New Mexico for most of this wildfire season thus far, but recent elevated temperatures and decreased humidity could change conditions quickly.  The current short-term forecast calls for increasingly hotter, drier, and breezy conditions, especially in southern Arizona (Fig. 6).  This could increase fire risk across the region, especially given the abundance of fine fuels stemming from above-average tropical storm activity late last fall. In the past week or so, we have already seen a number of lightning ignitions, although to date, fire managers are allowing these to burn to reduce fuel loads, further highlighting the beneficial impact of the extended period of cool and wet late-spring weather.


Image Source - National Interagency Coordination Center

Precipitation & Temperature Forecasts: The June 18 NOAA-Climate Prediction Center seasonal outlook predicts above-average precipitation for much of the Southwest and most of the Intermountain West this summer, with California, western Nevada, and southwest Arizona as notable exceptions. Temperature forecasts are split, with elevated chances for above-average temperatures along the West Coast and into Arizona (and most of the western U.S.), and increased chances for below-average temperatures in the midwestern U.S. and extending into eastern New Mexico (Fig. 7)


Image Source - NOAA/NWS - Climate Prediction Center

The Jetstream & El Niño - Looking back at 2014-2015, and forward to 2015-2016

Wednesday, May 27, 2015

Excerpt from the May 2015 Southwest Climate Podcast


Image & Story Credits

2015 El Niño Tracker

Friday, May 22, 2015

Originally published in the May 2015 CLIMAS SW Climate Outlook


El Niño continued for a third straight month, with no signs of weakening or dissipating. Forecasts keyed in on persistent sea surface temperature (SST) anomalies (Figs. 1–2), along with weakening trade winds, ongoing convective activity, and El Niño-related ocean-atmosphere coupling. If these conditions continue, we are likely to see the effects of a moderate El Niño event–or stronger if conditions continue to strengthen. Spring forecasts have a higher degree of uncertainty, owing to the so-called spring predictability barrier, a likely source of vacillations in recent forecasts. 

Image Source - Australian Bureau of Meteorology

Image Source - NOAA-National Climatic Data Center

Current forecasts offer a consistent and bullish forecast compared to last month, when they were integrating mixed signals regarding the strength of El Niño. On May 12, the Japan Meteorological Agency reversed course with an observation that strengthening El Niño conditions in the equatorial Pacific reflected an ongoing El Niño event that was likely to last through at least fall 2015. On May 12, the Australian Bureau of Meteorology upgraded its tracker to official El Niño status, identifying persistent SST anomalies, weak trade winds, and increasing ocean-atmospheric coupling serving as indicators this El Niño event was strong enough to extend into 2015. On May 14, the NOAA-Climate Prediction Center (CPC) extended its El Niño advisory with a 90 percent chance that El Niño will continue through summer 2015 and an 80 percent chance the event will last through 2015 (Fig. 3). The CPC pointed to positive SST anomalies, along with ongoing ocean-atmospheric coupling and dateline convection activity, as indicators of a weak to moderate El Niño event that will likely continue for most of 2015. On May 21, the International Research Institute for Climate and Society (IRI) and CPC forecasts confirmed we are in the midst of an El Niño event that appears to be strengthening, with the current forecast suggesting a moderate to strong El Niño event persisting into 2016. The North American multi-model ensemble shows a moderate event extending through the spring, with potential for a strong event by summer or early fall (Fig. 4).

Image Source - International Research Institute for Climate and Society

Image Source - NOAA-Climate Prediction Center

After a series of fits and starts, the pieces finally seem in place for the El Niño event forecasters expected to start last year. This is partially evidenced by the recent above-average precipitation and below-average temperatures in Arizona and New Mexico in late April and early May—exactly the sort of springtime weather we might expect to see if El Niño conditions were present and affecting our weather patterns. If the event persists into fall and winter 2015, and particularly if it remains a moderate to strong event, we will likely see patterns of above-average precipitation in the Southwest. There is also the possibility of a repeat of the 2014 tropical storm season, in which conditions favorable to El Niño were thought to have driven the increased tropical storm activity in the Southwest. 

Winter/Spring Recap 2014-2015

Friday, May 22, 2015

Originally published in the May 2015 CLIMAS SW Climate Outlook


It may not be news to anyone who follows weather forecasting and climate outlooks, but winter 2014–2015 did not play out as expected. Last year, long-term seasonal forecasts keyed in on conditions favorable to the development of an El Niño event and suggested we were more likely to see above-average precipitation in our winter months.  This was welcome news to a region that has been affected by a long-term and persistent drought, but rather than sustained above-average precipitation, we saw highly variable precipitation between October 2014 and April 2015 (Fig. 1) and cumulative water year-to-date precipitation that is below average across much of Arizona and parts of New Mexico (Fig. 2 on page 2).  Temperature was much less variable, with record or near-record warm average temperatures across most of the western U.S. (Fig. 4 on page 2). So what does this mean for some key areas of concern in the Southwest?

Snowpack and water supply:  The combination of below-average winter precipitation and above-average winter temperatures across the western U.S. meant there was less snow in the mountains and that it melted sooner in the season, which has implications for 2015 water supply. There was below-average precipitation overall, and precipitation that did occur often fell as rain instead of snow, with some losses to infiltration (owing to drier soils and the long-term drought) and sublimation (snow essentially evaporating associated with above-average temperatures and low relative humidity). Above-average temperatures also drove earlier-than-normal snowmelt, with most of the western U.S. recording well below-average snow, and many areas were snow-free far in advance of normal.  

Wildfire: The repeated incursions of precipitation associated with an above-average eastern Pacific tropical storm season and rainfall tied to typical monsoon patterns drove the growth of fine fuels in the Southwest.  This presents an increased fire risk when these fuels dry out, especially when the monsoon is ramping up and we see instances of dry lightning during building storms.  The counterpoint is our recent pattern of mild temperatures, increased humidity, and the occasional rainstorm, all of which have tamped down the wildfire risk in the Southwest. This can change quickly if we get the sustained period of windy weather with low relative humidity and high ambient temperatures that is typical of late May and early June. 

Pollen, Air Quality, and Human Health: The combination of precipitation last fall and elevated winter temperatures resulted in a banner year for wildflowers in the Southwest but also high pollen counts.  Seasonal allergy sufferers will almost certainly already be aware of this, but cumulative exposure to an increasing level and diversity of pollen likely affects those with only infrequent or occasional allergy symptoms as well. 

Image Source - NOAA/NWS - Advanced Hydrologic Prediction Service

Southwest Climate Outlook May 2015

Thursday, May 21, 2015

Originally published in the May 2015 SW Climate Outlook


Precipitation: In the past 30 days, most of New Mexico and much of central Arizona recorded well above-average precipitation (Fig. 1). Climatologically, this is one of the drier times of year for the Southwest, so any substantive precipitation during this timeframe is generally unexpected but welcome, as it helps tamp down fire risk. Water year observations since October 1 demonstrate the persistent and ongoing drought, with most western states, including Arizona, recording large areas of below-average to well below-average precipitation (Fig. 2). New Mexico and the eastern side of Colorado, Wyoming, and Montana have benefitted from some late season storms, but that rainfall on the other side of the Continental Divide, does not necessarily help the water situation in the Southwest.

Image Source - NOAA/NWS - Advanced Hydrologic Prediction Service

Image Source - NOAA/NWS - Advanced Hydrologic Prediction Service

Temperature: Lingering storms and above-average humidity contributed to mild and pleasant conditions across the Southwest, with temperature anomalies in Arizona and New Mexico between 2 and 6 degrees below average across the region in the past 30 days (Fig. 3). This counters more than six months of record or near-record warm average temperatures that have persisted in the Southwest and the western U.S. since the water year began on October 1 (Fig. 4).

Image Source - High Plains Regional Climate Center

Image Source - National Climate Data Center

Snowpack & Streamflow Forecasts: The late-season push for cooler than average weather had little impact on snowpack, and as of May 13, snow water equivalent (SWE) was far below average across the western U.S. (Fig. 5). Above-average temperatures and below-average precipitation, both contributing to a meager snowpack, were primary drivers in this pattern and resulted in below-average forecasts for streamflow (Fig. 6)

Image Source - Natural Resources Conservation Service - NRCS

Image Source - Natural Resources Conservation Service - NRCS

Drought & Water Supply: The U.S. Drought Monitor highlights persistent drought conditions across the West, with particularly severe conditions in California and Nevada, and emphasizes primarily long-term drought conditions across most of Arizona and much of New Mexico. Total reservoir storage was 44 percent in Arizona and 26 percent in New Mexico (see reservoir storage on for details). Below-average snowpack and above-average temperatures have resulted in earlier-than-normal melt-out in numerous areas and losses associated with sublimation and infiltration.

Wildfire: Mild spring weather, above-average precipitation, and relative humidity have resulted in reduced wildfire risk in Arizona and New Mexico so far this season. This can change quickly, especially since precipitation during the 2014 tropical storm season contributed to abundant fine fuels, which can escalate wildfire risk when the region eventually dries out. An early or even on-time start to the monsoon could limit the window of highest wildfire risk, but a delayed start could extend it, especially given the dry lightning associated with summer storms.

Precipitation & Temperature Forecasts: The May 21 NOAA-Climate Prediction Center seasonal outlook predicts above-average precipitation this spring into summer for much of the Southwest and Intermountain West, although California and most of Arizona are notable exceptions. Temperature forecasts remain split across the region, with elevated chances for above-average temperatures along the West Coast and eastward into Arizona (and most of the western U.S.), and increased chances for below-average temperatures in western Texas and into eastern New Mexico.


Also in this issue:


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Monsoon Climate & Wildfire - What Does Winter-Spring Weather Mean for Wildfire Season

Friday, May 15, 2015

Excerpt from the May 2015 Southwest Climate Podcast


Image & Story Credits

Mini-Podcast/News - Southwest Climate Update - May 1, 2015

Monday, May 4, 2015

We're introducing a new podcast series that focuses on quick and timely reporting on important climate news and information. We will emphasize stories that relate to the southwest, but we'll also include other climate related news that illustrate the impact of climate on national or global scales.  And Mike, Zack, and Ben will still take a deeper look at southwestern climate issues in the monthly CLIMAS Southwest Climate Podcast. This episode, we're focused on record warm temperatures, drought, and snowpack across the west, along with a few stories that illustrate the downstream impact of these conditions.


2014 Was a Record Warm Year - 2015 May Challenge This Record

Globally, 2014 was the warmest year on record.  This pattern was repeated in the southwest, where Arizona, California, and Nevada all had record warm average temperatures in 2014, while New Mexico, Utah, Idaho, Washington, and Oregon were all in the top 5 of warmest years on record (Fig. 1). 

2015 is continuing this trend, where the January – March 2015 saw record warm average temperatures for 7 states, Arizona, California, Nevada, Utah, Wyoming, Washington and Oregon, while Montana, Idaho, Colorado and New Mexico were all in the top 10 warmest on record(Fig. 2). 

Besides concerns about a gradually warming climate, these record warm temperatures, along with below average water-year precipitation across much of the west, have resulted in far below average snowpack levels (see below) which is cause for concern regarding drought and water storage looking into 2015.


State of the Drought

The current drought is ongoing and long term.  It is especially severe in California, but it is still affecting most of the west and portions of Midwest (Fig. 3). 

In Arizona the drought is leading AZ to think about Water Planning. Arizonan’s should not expect the same drastic steps that were taken in California in early April to preserve water.  Arizona and California don’t get water from the same supply, and much of California’s problems stem from the lack of snow in northern California, along with increasing demand from both agricultural and municipal users. 

Both states do get water from the Colorado River (Fig. 4), but as of yet, neither has seen mandatory reductions, although water managers are closely monitoring Lake Mead with projections it might drop to 1075’ within the next few years (Fig. 4 inset) – which would trigger mandatory reductions in some allocations. Arizona water leaders are concerned about the drought, but they have been planning for possible shortages for decades.


Bark Beetles are attacking trees that are stressed by climate change

Drought and warmer temps aren’t the only things that come with climate change.  These changes also alter the ecosystem dynamics as plants and animals respond to climate stressors. Bark Beetles are tiny winged beetles that have been attacking North American forests for a long time.  But lately these beetles have gone into overtime and are attacking trees that are stressed by climate change (Fig. 5). 

Trees that were “born” during mini-ice age in 1800s are stressed by warming trends and the beetles are exploiting the reduced defenses associated with this stress. They are sometimes felling as many as 100,000 trees a day.  Other genetic sub-populations that are more adapted to warmer temperatures are more resilient and the beetles don’t hit them as hard (or at all). Because of droughts and shorter winters, the trees are more stressed, and fewer beetles are killed off in winter freezes, and bark beetles have killed billions of trees in what will probably be the largest forest insect outbreak ever.  10 times the size of any past outbreak.

Some real estate agents have seen the prices of home plummet from “viewshed contamination” in areas destroyed by the bugs (Fig. 6).  As climate change continues to warm the forests in North America, these bugs are expected to continue to thrive.  This means more beetles in the future, preying on bigger chunks of forested areas across the county.


Snowpack in the West

Record low snowpack plus the drought have led to California enacting restrictions on water. A statewide snow survey found that the water content of California’s snowpack was only 5 percent of the April 1st average.  This is by far the lowest reading for that date. The previous record lowest snowpack for April 1st was 25 percent of average in records dating back to 1950.

This survey on the Sierra snowpack at the Phillips Station was performed on grass for the first time ever.  About 1/3 of California’s drinking water comes from the Sierra snowpack.  So on April 1st California Gov. Jerry Brown announced mandatory statewide water restrictions for the first time in state history.

One way to understand this snow deficit is to look at Tahoe City, California.  From October 1, 2014 through March 31st 2015 only 19.5 inches of snow had fallen.  That is 143.1 inches below average.  Almost 12 feet less of snow!  An airborne snow survey was conducted by NASA’s Jet propulsion Laboratory over the Tuolumne River Basin on March 25th and the snowpack water content is 34 billion gallons less than last spring.  California has had a wetter April but as is the case with the drought across the western united stats - to make a dent in a multiyear drought, it requires multiple years of above average precipitation.


Snowpack & Drought: Impact on Energy Systems

The California drought is also having an impact on energy. From an article by the U.S. Energy Information Administration, these dry conditions are limiting hydropower generation and requiring generation from other sources to make up for this short fall. (Fig. )

20 percent of California’s generation came from hydropower during the first 6 months of each year from 2004 to 2013.  However, during the first half of 2014, only 10 percent of California’s generation came from hydropower. (Fig. )

California is turning to natural gas to make up for the loss in generation.  When a month’s hydropower generation dips under 10-year average levels, monthly natural gas generation often rises above its average. Wind and solar are also helping in the fight.  Wind generation surpassed hydro generation in California for the first time in February and March of 2014. (Fig. )


Climate Change & Pollen

Warmer temperatures, combined with a wet fall have resulted in a very heavy pollen season this year.  Pollen grains are used by plants for fertilization and reproduction. but for humans pollen isn’t so nice.  It can cause respiratory problems like hay fever and asthma.  These allergic triggers come from the pollen made by trees, weeds and grasses.  As temperatures rise and we experience changes in precipitation the growth and distribution of pollen is being affected worldwide.

 According to the National Climate Assessment and other recent publication, warmer air temperatures and more frost-free days have advanced the start time of pollen production.  This is leading to an earlier and longer pollen season.  Also because the levels of CO2 have increased, this has enhanced photosynthesis making pollen-producing plants bigger.  Bigger plants, more pollen, more allergies.  Warming temperatures have changed the spatial distribution of pollen. Ragweed, a rare type of pollen for the United Kingdom, was reported at record levels for the first time in the East Midlands in September of 2014. In 2001 7.3 percent of the U.S. suffered from asthma.  In 2010 the number rose to 8.4 percent.  The scientific community believes climate change could be contributing to this change. 


Image & Story Credits - Podcast & Blog Post


2014 and 2015 Record Temperatures


State of the Drought


Bark Beetles, Tree Stress, and Climate Change


Record Low Snowpack Across the West 


Snowpack, Drought, & Energy


Climate Change, Temperature & Precipitation Records, and Pollen

El Niño Tracker - April 2015

Friday, April 17, 2015

This was originally published in the April 2015 Southwest Climate Outlook


Strong signals in early 2014 stalled, delaying El Niño’s onset until last month, when ocean-atmosphere coupling and an additional Kelvin wave indicated more favorable conditions. Despite this late start, El Niño continued for a second consecutive month. Recent increases in sea surface temperature (SST) anomalies (Fig.1 - 2) and ongoing convective activity associated with El Niño-favorable conditions indicate we might be witnessing a two-year El Niño event. These forecasts rely on projections during a time of increasing uncertainty, and the so-called “spring predictability barrier” continues to make it difficult to anticipate how seasonal changes will help or hinder El Niño. 

Image Source - Australian Bureau of Meteorology

Image Source - NOAA-National Climatic Data Center

The most recent forecasts continue to offer mixed signals regarding El Niño, but are more bullish this spring than last year. On April 9, the NOAA-Climate Prediction Center (CPC) issued an El Niño advisory with a 70 percent chance that El Niño will continue through summer 2015 and more than a 60 percent chance the event would last through fall.  They pointed to the large Kelvin wave, along with ongoing ocean-atmospheric coupling, as an indication a weak El Niño event would linger, with potential for further development in the long term. On April 10, the Japan Meteorological Agency declared the El Niño event likely to have ended in winter 2015, with current conditions being ENSO-neutral, but also projected El Niño conditions could return by summer.  On April 14, the Australian Bureau of Meteorology upgraded their tracker to “alert” status (one below an official El Niño designation), with warming in the tropical Pacific, weak trade winds, and projected additional ocean warming listed as contributing factors. On April 16, the International Research Institute for Climate and Society (IRI) and CPC forecasts highlighted increasingly favorable oceanic and atmospheric conditions, with an 80 percent probability of El Niño extending from summer into fall, and a 70 percent probability of El Niño extending into next winter (Fig. 3).  The North American multi-model ensemble shows a weak event extending through the spring, with potential for a moderate or even strong event by summer or early fall (Fig. 4).

Image Source - International Research Institute for Climate and Society

Image Source - NOAA-Climate Prediction Center

This El Niño event continues to defy expectations, with some models indicating conditions are strengthening rather than weakening during the spring transition.  Forecasting or characterizing this event remains difficult given the lack of analog events in the historical record, and the complexity of this El Niño guarantees it will be of interest to climatologists for years to come. Seasonal forecasts continue to indicate an increased chance of above-average precipitation through much of the Southwest, likely tied to the presence of El Niño favorable conditions. Perhaps more interesting is the possibility of a repeat of 2014’s tropical storm season, when conditions favorable to El Niño were thought to have been driving increased storm activity in the Southwest.

Southwest Climate Outlook April 2015 - Climate Summary

Thursday, April 16, 2015

Precipitation: In the past 30 days, most of the southwestern U.S. received below-average precipitation (Fig. 1). The winter wet season is wrapping up, and instead of above-average precipitation (as many of the El Niño influenced seasonal forecasts suggested), water year observations since October 1 show below-average precipitation across much of Arizona and portions of New Mexico. The situation is direr in other western regions, with California, the Pacific Northwest, and the Intermountain West recording significantly below-average winter precipitation (Fig. 2). 

Image Source - NOAA/NWS - Advanced Hydrologic Prediction Service

Image Source - NOAA/NWS - Advanced Hydrologic Prediction Service

Temperature: In the past 30 days, temperatures were above-average across Arizona and New Mexico, with anomalies between 4 to 8 degrees F above average across most of the region (Fig 3). In the six months since the water year began on October 1, Arizona, California, Nevada, Oregon, and Washington saw record-warm average temperatures (Fig. 4).

Image Source - High Plains Regional Climate Center

Image Source - National Climate Data Center

Snowpack: High temperatures and below-average precipitation led to limited snowpack across the western U.S.  As of April 16, snow water equivalent (SWE) is below average in every basin in the West (Fig. 5). In our region, SWE ranged from 0 to 32 percent of average in Arizona and 0 to 50 percent of average in New Mexico.

Image Source - Natural Resources Conservation Service - NRCS

Drought & Water Supply: The U.S. Drought Monitor highlights persistent drought conditions across the West and identifies both short- and long-term drought conditions in Arizona and New Mexico. Total reservoir storage in March was 45 percent in Arizona (same value as last year) and 26 percent in New Mexico (compared to 24 percent last year) (see reservoir storage on page 5 for details). 

Wildfire: There is potential for wildfire in any month of the year, but March through June is the windiest time of year (see page 4), which increases likelihood of red flag warning days.  This is also one of the driest times of the year, so all eyes are on fire risk potential from now through the onset of the monsoon.

El Niño: Despite a relatively late start, El Niño continued for a second consecutive month, with potential for a stronger event as we look forward towards summer and fall of this year (see page 3 for details).

Precipitation & Temperature Forecasts: The April 16 NOAA-Climate Prediction Center seasonal outlook predicts above-average precipitation this spring into summer for most of the Southwest and Intermountain West, although California and southern Arizona are notable exceptions. Temperature forecasts remain split across the region, with elevated chances for above-average temperatures along the West Coast and eastward into Arizona (and most of the western U.S.), and increased chances for below-average temperatures in western Texas and into eastern New Mexico.

Streamflow Forecasts: The April 1 forecast for the Colorado, Rio Grande, and Arkansas river basins project well below-average streamflow for Arizona and New Mexico. This pattern is repeated across much of the western U.S., especially in Utah, Nevada, California, New Mexico, and Arizona (Fig. 6), following the unusually warm and dry conditions in March. 

Image Source - Natural Resources Conservation Service - NRCS

Spring Signals the Start of Wildfire Season for the Southwest

Wednesday, April 15, 2015

A version of this post was also published in the April 2015 Southwest Climate Outlook


Flowers are blooming and trees have sprouted green leaves, signs that spring is in full swing across the Southwest and that, despite a verdant desert, wildfire season is upon us. The outlook for this wildfire season forecasts near-average wildfire activity for much of Arizona and New Mexico.

Several factors, including gradually increasing temperatures, a decreasing probability of precipitation, and increasing wind, create perfect climatological conditions for wildfire. From a climate perspective, spring is also a transition season, when the winter storm track lifts north and the sub-tropical high pressure system to the south starts to build north, both in response to an increasing sun angle and increased heating of the Northern Hemisphere. The retreat of the winter storm track and advancement of the sub-tropical ridge is generally not a clean transition, but a battle of cool and warm air masses that plays out over weeks, if not months. In this battle, the atmospheric pressure gradient tightens and wind speeds increase in response, creating conditions that can cause wildfires to grow quickly. In Arizona and New Mexico, hot, dry, and windy conditions are often the norm in late spring, and not surprisingly, this forms the heart of wildfire season for this part of the Southwest. 

Spring wildfire activity can be modulated by conditions from the previous winter, the previous summer, or even several years prior. Long-term drought conditions can stress and kill trees, increasing fire risk, but wet winters and strong monsoons can also drive increased fire risk. Fast-growing vegetation like grasses and annuals grow quickly during wet periods, then dry out and become fine fuels for subsequent wildfire seasons. 

The current wildfire outlook for the southwest notes that near-average wildfire activity is expected for much of Arizona and New Mexico, due largely to some improvements in drought conditions across the region, including above average precipitation last summer and into the early winter season. But this precipitation also spurred on new vegetation growth, increasing the risk of wildfires across southern Arizona this spring as this vegetation senesces and becomes flammable.  Fire managers will be watching these emergent conditions carefully, especially as dry and windy conditions create short-term windows of elevated fire risk.

Image Source - National Interagency Coordination Center

Image Source - National Interagency Coordination Center

Southwest Winter Climate Update (2014-2015)

Tuesday, March 31, 2015

This mini-segment was taken from the Mar 2015 Southwest Climate Podcast


Image & Story Credits

El Niño Tracker - March 2015

Friday, March 20, 2015

Originally published Mar 19, 2015 in the CLIMAS Southwest Climate Outlook

After months of vacillating sea surface temperature (SST) anomalies, limited coordination between oceanic and atmospheric conditions favorable to El Niño formation, and ongoing confusion regarding the strength of the various diagnostic signals, El Niño has “officially” arrived in North America. This is late in the season to declare an El Niño, and the so-called spring predictability barrier makes it difficult to anticipate how seasonal changes, particularly westerly wind bursts, will help or hinder the ongoing conditions favorable to El Niño. This has been a strange season.  Strong signals in early 2014 stalled in summer and into fall, delaying the event’s onset until this month, when ocean-atmosphere coupling and an additional Kelvin wave again indicated more favorable conditions for an El Niño event.

The most recent forecasts offer mixed signals regarding El Niño. On Mar. 5, the NOAA-Climate Prediction Center (CPC) issued an El Niño advisory, maintaining a 50–60 percent probability of a weak El Niño event developing and extending through the summer. On Mar. 10, the Japan Meteorological Agency declared the El Niño event likely to have ended, with greater likelihood of a return to El Niño than ENSO neutral conditions in the summer. On Mar. 17, the Australian Bureau of Meteorology elevated its El Niño tracker from neutral back to watch status, noting the “unusual conditions” in the tropical Pacific, including warmer-than-average SST anomalies (Fig. 1-2). On Mar. 19, the International Research Institute for Climate and Society (IRI) and CPC reasserted a 50–60 percent probability of this El Niño event extending into summer 2015 (Fig. 3), similarly noting atypical (or even strange) conditions that have made characterizing this particular event difficult.  The North American multi-model ensemble shows a weak event extending into summer (Fig. 4), and corroborates the forecast discussion that suggests an increased possibility of a stronger El Niño signal extending into 2016.  While the models are bullish on the possibility of a moderate to strong event, this will depend on how ocean and atmospheric conditions progress from summer into fall. 

With a seemingly definitive El Niño declaration, we are finally out of “El Limbo”.  While forecasting or characterizing this event has been difficult for all involved, the complexity of this El Niño will be of interest to climatologists for years to come.  Looking forward, seasonal forecasts still indicate an increased chance of above-average precipitation through much of the Southwest for late winter and spring. Despite numerous storm events, we have yet to see widespread and sustained above-average winter precipitation in the Southwest, which would help considerably in mitigating longer-term drought conditions.

Image Source - Australian Bureau of Meteorology

Image Source - NOAA-National Climatic Data Center

Image Source - International Research Institute for Climate and Society

Image Source - NOAA-Climate Prediction Center

Southwest Climate Outlook March 2015

Thursday, March 19, 2015

Originally published Mar 19, 2015 in the CLIMAS Southwest Climate Outlook

Precipitation: In the past 30 days, precipitation was below average in much of southern Arizona, above average in portions of northern Arizona and southern New Mexico, and near normal across much of the rest of the region (Fig. 1). Precipitation totals for the water year (since Oct. 1) are below average across all of Arizona and most of New Mexico and are even worse in other western areas; California, the Pacific Northwest, and the Intermountain West are recording significantly below-average winter precipitation (Fig. 2).

Image Source - NOAA/NWS - Advanced Hydrologic Prediction Service

Image Source - NOAA/NWS - Advanced Hydrologic Prediction Service

Temperature: In the past 30 days, temperatures in nearly all of Arizona ranged from 0 to 6 degrees F above average. The western half of New Mexico was warmer than average, while the eastern half was cooler (Fig. 3). Regionally, winter 2014-2015 has seen a continuation of well above-average temperatures across much of the western U.S.

Image Source - High Plains Regional Climate Center

Snowpack & Water Supply: Snow water equivalent (SWE) is very low in most of Arizona (ranging from 2 to 74 percent of average) and much of New Mexico (ranging from 11 to 111 percent of average), although Califonia and the Pacific Northwest are at even lower levels (Fig. 4). Well above-average temperatures continue to have a significant effect on snowpack, pushing the snowline higher and driving early snowmelt runoff. In January, total reservoir storage was 45 percent in Arizona (compared to 46 percent last year) and 24 percent in New Mexico (compared to 23 percent last year) (see reservoir storage on page 4, for details). 

Image Source - Natural Resources Conservation Service - NRCS

Drought: Long-term drought conditions persist across the West, and the U.S. Drought Monitor continues to document long-term drought conditions across much of Arizona and New Mexico (Fig. 5).  

Image Source - National Drought Mitigation Center

Plant Ecology & Human Health: Above-average temperatures and winter rains jumpstarted plant activity across the region, and the Southwest is experiencing a banner year for wildflowers. This beauty comes at a cost; pollen levels are high enough to affect most allergy sufferers and are expected to remain that way through the spring.

El Niño: El Niño finally arrived, and will likely remain a weak event this spring and into summer. Forecasts suggest El Niño could escalate to a moderate to strong event in 2015-2016 (see ENSO Tracker on page 3).

Precipitation & Temperature Forecasts: The Mar. 19 NOAA-Climate Prediction Center seasonal outlook continues to predict above-average precipitation this spring for most of the Southwest. Temperature forecasts remain split across the region, with elevated chances for above-average temperatures along the West Coast and eastward into Arizona (and the western U.S.) and increased chances for below-average temperatures across Texas and into New Mexico (Fig. 6).

Image Source - NOAA-Climate Prediction Center

Streamflow Forecasts: The Mar. 1 forecast for the Colorado, Rio Grande, and Arkansas river basins projects well below-average streamflow for most of Arizona and New Mexico, with the exception of north-central New Mexico and a few isolated locations in Arizona (Fig. 7).

Image Source - Natural Resources Conservation Service - NRCS

Winter of Weather (2014-2015)

Monday, February 23, 2015

 


This mini-segment was taken from the Jan 2015 SW Climate Podcast


Image & Story Credits

El Niño Tracker - Southwest Climate Outlook February 2015

Friday, February 20, 2015

Originally published in the Feb 2015 CLIMAS Southwest Climate Outlook

2014-15 El Niño Tracker

A definitive 2014–2015 El Niño forecast remains elusive. Weak El Niño conditions have continued in 2015, but recent backsliding in SST anomalies (Fig. 1), especially in the Niño 1-2 regions (Fig. 2), along with the ongoing lack of coordination between atmospheric and oceanic conditions, give little confidence that the 2014–2015 event will be characterized as anything more than a weak El Niño.

Image Source - Australian Bureau of Meteorology

Image Source - NOAA-National Climatic Data Center

The most recent forecasts dialed back the probabilities for El Niño this winter and spring, and hinted we could swing to ENSO-neutral by late spring. On Feb. 5, the NOAA-Climate Prediction Center (CPC) issued another El Niño Watch, maintaining a 50–60 percent probability of an El Niño event, most likely a weak event extending into late winter or early spring. On Feb. 10, the Japan Meteorological Agency continued its assessment that El Niño conditions had been present in the equatorial Pacific for multiple months. They noted uncertainty as to the length or intensity of an El Niño event, with emphasis on a weak event that would transition to ENSO-neutral by early spring. On Feb. 17, the Australian Bureau of Meteorology kept its El Niño tracker status at neutral, given the fade in SST anomalies and lack of clear atmospheric signal. On Feb. 19, the International Research Institute for Climate and Society (IRI) and CPC reasserted a 50–60 percent probability of an El Niño event (Fig. 3).  Given the declining SST anomalies and lack of clear atmospheric signal, they characterized this event as a “borderline El Niño” that would last through early spring 2015. The North American multi-model ensemble shows a weak event that extends into summer (Fig. 4). This graph highlights the possibility of a continuation of a stronger El Niño signal into 2015 (a possibility that was discussed in the IRI-CPC forecast event), depending on how ocean and atmospheric conditions progress from summer into fall.  The dynamical models currently favor a resurgence of El Niño conditions, while the statistical models suggest an ENSO-neutral state.

As with last month, we remain in “El Limbo” with seasonal forecasts still indicating an increased chance of above-average precipitation across the Southwest for winter and early spring. These forecasts are linked to the projected influence of El Niño conditions, but impacts associated with weak El Niño events are less certain than those associated with moderate or strong events (past weak events have brought both dry and wet conditions to the Southwest during the winter). A number of storm events have moved through the Southwest in late 2014 and early 2015, but conditions have not converged to produce widespread above-average precipitation over an extended period of time.  For this El Niño event to be of some utility in mitigating longer-term drought conditions, we would hope to see this convergence this winter into spring, with more widespread and sustained precipitation events.

Image Source - International Research Institute for Climate and Society

Image Source - NOAA-Climate Prediction Center

Notes from an Applied Climatologist: East/West Cold/Hot Dichotomy Q&A

Friday, February 20, 2015

Originally published in Feb 2015 CLIMAS Southwest Climate Outlook:


Why has it been so cold on the East Coast, and so warm in the Southwest?  Where does this fit into climatic patterns?  And is this extraordinary or just variability?

The weather pattern across the U.S. has been pretty extreme over the past weeks, with record cold and snow across the East and record to near-record warmth in the West. Why is the country so divided? In short, a wavy jet stream is to blame (Fig. 1). This high-altitude stream of fast-moving winds has been carving a circuitous path around the globe for much of the winter. The path of the winter mid-latitude jet stream around the globe (in both hemispheres) can give a good indication of where storms are tracking and where warm and cold spots at the surface are emerging. If the jet stream gets stuck in any position, then places getting storms can continue to see a parade of storms, while warm and dry places stay warm and dry. 

Image Source - NOAA-Earth Systems Resarch Laboratory (ESRL)

This winter, the mid-latitude jet stream in the Northern Hemisphere has been very wavy, or meridional [1], with ridges—large-scale bulges—to the north and troughs to the south. Ridges are associated with warm and dry conditions, while troughs are associated with cold and possibly snowy or rainy conditions. Over the past several weeks, this warm West/cold East pattern has dominated, with a persistent ridge of high pressure across the West and a very cold trough across the East (Fig. 2).  Last year, similar conditions drove California and much of the Southwest deeper into drought and unleashed record-setting cold [2] in the eastern U.S. This year, these conditions have broken down on occasion, allowing for storms to bring some precipitation to the West and for the East to warm up for brief periods.

Researchers are trying to determine why this dichotomous pattern has emerged and persisted over the past couple of years. Some climate scientists propose that a warming Artic and declining sea ice [3] are contributing to an increasing frequency of wavy and stuck jet stream events. Other scientists argue that warming water [4] in the tropics and shifts in tropical convection are at play in impacting the winter jet stream pattern. This winter appears to be a complex interaction of many different factors [5] and will be studied in more detail over the coming year to see how it fits into these active areas of research.

Image Source - NOAA-ESRL & Climate.gov

Additional Resources

  1. Meridional: In meteorology, a flow, average, or functional variation taken in a direction that is parallel to a line of longitude; along a meridian; northerly or southerly; as opposed to zonal. 
  2. U.S. temperature extremes and the polar jet stream
  3. Evidence for a wavier jet stream in response to rapid Arctic warming
  4. Record-breaking winters and global climate change
  5. Synoptic Discussion - January 2015

El Niño Tracker - January 2015

Friday, January 23, 2015

Originally published in the January 2015 Southwest Climate Outlook (SWCO)

Just when it looked like we were getting a more definitive answer regarding El Niño, ongoing lack of cooperation on the part of the atmosphere continues to muddy forecasts moving into 2015. Sea surface temperatures (SSTs) remain elevated across much of the equatorial Pacific Ocean (Fig. 1), and while temperature anomalies in the Niño 3.4 region are within the range of a weak El Niño event, they have declined in the past month (Fig. 2). It is a common refrain in forecast bulletins that a lack of coupling between ocean and atmosphere is responsible for decreased confidence in an El Niño event this winter. Additionally, a lack of temperature gradient along the equatorial Pacific and little in the way of El Niño wind patterns further reduce confidence that a stronger event is on the horizon.

Source: Australian Bureau of Meteorology

Source: NOAA-National Climatic Data Center

The most recent forecasts remain in a cautious holding pattern, pending the emergence of a more decisive signal. On Jan. 8, the NOAA-Climate Prediction Center (CPC) issued another El Niño Watch, assigning a 50 to 60 percent probability that an El Niño would form in the next two months, with forecaster consensus that this would be a weak event extending into late winter or early spring. On Jan. 9, the Japan Meteorological Agency continued its assessment that El Niño conditions had been present in the equatorial Pacific for multiple months but noted uncertainty as to the length or intensity of an El Niño event, with emphasis on a weak event that would transition to ENSO-neutral by early spring. On Jan. 15, the International Research Institute for Climate and Society (IRI) and CPC scaled back the probability of an El Niño formation to approximately 60 percent (Fig. 3) but indicated SST anomalies were sufficient enough to suggest a weak El Niño event was likely underway and would last through spring 2015. On Jan. 20, the Australian Bureau of Meteorology actually shifted its El Niño tracker status to neutral, given the fade in SST anomalies and lack of clear atmospheric signal. The North American multi-model ensemble shows a weak event that extends into summer (Fig. 4). 

Source: International Research Institute for Climate and Society

Source: NOAA-Climate Prediction Center

Vacillations in forecast percentages prompted the forecast community to describe current conditions as “El Limbo.” Despite lack of official status, El Niño-like conditions may already be driving winter patterns, and seasonal precipitation forecasts indicate an enhanced chance for above-average precipitation this winter across the Southwest, although confidence in this forecast is partially contingent on the strength of these El Niño conditions. Impacts associated with weak El Niño events are generally less certain than those of a moderate or strong event, with past weak events bringing both dry and wet conditions to the Southwest U.S. during the winter. Ultimately, the above-average tropical storm season and the humidity that remained in the region may be indicative of the effect of El Niño-like conditions, even in the absence of a formal designation, and give some idea that the regional patterns have shifted in favor of El Niño formation.

Southwest Climate Outlook January 2015

Thursday, January 22, 2015

In the Jan 2015 Southwest Climate Outlook, we look back at 2014, including record temperatures for the Southwest, the recent trends in precipitation and drought, and forward into 2015 as we continue to wait for El Niño to give us a definitive answer.


Climate Summary/Forecasts

Precipitation: After an exceptionally dry November, a number of storms pushed into the Southwest in December and early January, but overall precipitation totals were highly variable across Arizona and New Mexico (Fig. 1). 

Source: High Plains Regional Climate Center - HPRCC

Temperature: December continued the yearlong trend of above-average temperatures, with Arizona logging the warmest year on record in 2014 (as did California and Nevada), and New Mexico at near-record levels (Fig. 2). The extended warm temperatures were in part attributable to well above-average humidity that extended long after the monsoon ended.  In particular, this kept nighttime lows above average, and we did not experience the typical pattern of cooling off and drying out in early fall.

Source: NOAA-National Climatic Data Center

Snowpack: While still relatively early in the season, snow water equivalent (SWE) remains low across Arizona and New Mexico, ranging from 0 to 70 percent of average in Arizona and 50 to 90 percent of average for most of New Mexico.  SWE in the upper elevations that feed into Arizona and New Mexico are faring a little better, with most of the basins reporting more than 70 percent of average and many reporting between 90 and 110 percent of average (Fig. 3).

Source: Natural Resources Conservation Service - NRCS

Water Supply: In December, total reservoir storage was 45 percent in Arizona (compared to 47 percent last year) and 23 percent in New Mexico (compared to 22 percent last year) (see reservoir storage, for details).

Drought: Continued consistent and repeated precipitation events, especially with El Niño-led above-average precipitation throughout the winter and spring, would push us in the right direction regarding long-term drought conditions. Alleviating the drought will take time however; widespread areas of the Southwest received well below-average precipitation over the past 12 to 36 months, with the Four Corners region, northeast New Mexico, and portions of southern Arizona experiencing the largest deficits in the past 12 months (Fig. 4).

Source: High Plains Regional Climate Center - HPRCC

ENSO: The most recent NOAA-Climate Prediction Center forecast scaled back its forecast for El Niño this year, albeit only slightly.  Ongoing lack of atmospheric cooperation continues to sow confusion, despite generally above-average temperature anomalies in the Niño 3.4 region (see El Niño tracker, for details).

Precipitation Forecasts: The Jan. 15 NOAA-Climate Prediction Center seasonal outlook continues to predict above-average precipitation through the winter and into early spring for the southwest. This forecast is likely linked to El Niño-favorable conditions, but the extent of their impact remains to be seen (Fig. 5).

Temperature Forecasts: The Jan. 15 NOAA-Climate Prediction Center temperature forecasts remain split across the region, with elevated chances for above-average temperatures along the West Coast and eastward into Arizona and increased chances for below-average temperatures along the Gulf Coast into New Mexico. This pattern is projected through the winter and into the spring (Fig. 6).

Source: NOAA-Climate Prediction Center

Jan 2015 SW Climate Podcast: 2014 Year in Review, and Stuck in El Limbo

Wednesday, January 21, 2015

In the January Southwest Climate Podcast, Zack Guido is back and joins Mike Crimmins to discuss the state of the climate in 2014, including the record year for Arizona and the near record year for New Mexico.  They also talk about weather systems that affected our most recent temperature and precipitation patterns, the ongoing uncertainty with El Niño, or as some have started referring to it, "El Limbo", and the state of precipitation and drought in the southwest.  They wrap things up looking at the seasonal outlooks and the projected trends for the coming year. 

Intro 0:00
Climate Summary: Temperature and Precipitation, weak and spotty storms in December and January 1:50
Winter Storms: Water storage and winter precipitation patterns 8:00
Weather vs. Climate: Weather variability vs. Climate patterns, "El Limbo", and winter precip patterns given these trends 13:00
2014 Record Year: 2014 Temperature Records Recap 22:00
Precip and Drought: Winter patterns and drought - how much moisture "solves" the drought  24:00
Looking Forward: Jetstreams & Winter Weather Patterns + Seasonal Forecasts 27:30

If you have a question you'd like answered, you can email Zack Guido (zguido@email.arizona.edu) or Ben McMahan (bmcmahan@email.arizona.edu) with "CLIMAS Podcast Question" in the subject line. You can also tweet us @CLIMAS_UA or post a question on facebook

Transcript: Coming Soon

Suggested Source/Citation:

CLIMAS: Climate Assessment for the Southwest, (2015). 2014 Year in Review, and Stuck in El Limbo . [podcast] CLIMAS Southwest Climate Podcast. Available at: climas.arizona.edu/podcast/jan-2015-sw-climate-podcast-2014-year-review-and-stuck-el-limbo [Date Accessed]

El Niño Tracker Update - December 2014

Friday, December 19, 2014

From the Dec 18, 2014 - Southwest Climate Outlook - 

We are still waiting for a decisive signal, but conditions indicate we are near, or possibly already into, at least a weak El Niño event. Sea surface temperatures (SSTs) are elevated across the equatorial Pacific Ocean (Fig. 1), and the measurements in the Niño 3.4 region are indicative of El Niño having already started (Fig. 2).

There remains a distinct lack of cooperation on the part of the atmosphere. This lack of coupling between ocean and atmosphere (demonstrated by near-normal wind and rainfall anomalies), along with a lack of temperature gradient along the equatorial Pacific and little in the way of El Niño wind patterns, means that while we are likely already experiencing El Niño-like conditions in the Southwest (e.g. some of the recent wet weather), it may be a little longer before a formal declaration occurs, even if retroactively.  

On Dec. 4, the NOAA-Climate Prediction Center (CPC) issued another El Niño Watch, with a 65 percent probability of a weak El Niño event occurring.  Anomalous SSTs alone were probably enough to suggest a weak El Niño event, but the lack of atmospheric coupling kept the current assessment at ENSO-neutral.  On Dec. 10, the Japan Meteorological Agency declared that an El Niño started in late summer and that it would continue through early 2015. This was based on favorable El Niño conditions and elevated SSTs, even while other more robust criteria were not yet met. On Dec. 16, the Australian Government’s Bureau of Meteorology maintained its El Niño tracker status at El Niño Alert status, despite a lack of atmospheric conditions to complement the anomalous SSTs. That outlook assigned a 70 percent probability of a weak El Niño event developing in winter 2014–2015. The Dec. 18 International Research Institute for Climate and Society (IRI) and CPC upped the probability of El Niño conditions developing to more than 80 percent in the next three months and more than 70 percent through spring and into summer (Fig. 3).

The North American multi-model ensemble shows a weak event that extends well into spring (Fig. 4). The extended period of above-average SSTs appears to be increasing confidence in the formation of El Niño this winter into spring.

Seasonal precipitation forecasts still indicate an enhanced chance of above-average precipitation over the upcoming winter, but confidence in this forecast is partially contingent on the strength of the emerging El Niño event. The impacts associated with weak El Niño events are generally less certain than those of a moderate or strong event, with past weak events bringing both dry and wet conditions to the Southwest U.S. during the winter. Ultimately, the above-average tropical storm season and the humidity that has remained in the region may be indicative of the effect of El Niño-like conditions, and we may be seeing the emergent effects of El Niño impacts on the climate of the Southwest, despite the absence of a formal definition identifying the start of a bounded El Niño event.

Southwest Climate Outlook Dec 2014

Thursday, December 18, 2014

Taken from the Dec 18, 2014 - Southwest Climate Outlook - 


Precipitation: November was particularly dry in Arizona and New Mexico, with many locations recording no measureable precipitation (Fig. 1). A few events in December brought widespread moisture to the region, but actual measureable precipitation was still relatively low despite these incursions. The dew point remains well above seasonal averages, likely related to the persistent tropical activity and the conditions that favor the formation of an El Niño event. 

Source: High Plains Regional Climate Center - HPRCC

Temperature: Arizona and New Mexico were warmer than average over the past 30 days (Fig. 2), continuing a yearlong trend, and Arizona is on track for the warmest year on record. The persistently high dew point is also related to observed temperature, as we have yet to see an extended cool/dry period that brings lower nighttime temperatures to the region.

Source: High Plains Regional Climate Center - HPRCC

Snowpack & Water Supply: Snow water equivalent (SWE) is low across Arizona and New Mexico, ranging from 0 to 50 percent of average in Arizona and 0 to 90 percent of average in New Mexico (Fig. 3). Despite a few widespread snowfall events, high temperatures and below-average precipitation have led to lower-than-average snowpack levels across the region. In October, total reservoir storage was 45 percent in Arizona (compared to 47 percent last year) and 22 percent in New Mexico (compared to 22 percent last year). 

Source: Natural Resources Conservation Service - NRCS

Drought: The monsoon and tropical storm season brought seasonal rainfall totals close to or above average across Arizona and New Mexico, but these intense storms provided limited long-term drought relief, with widespread areas well below-average over the past 12 to 36 months (Fig. 4). The Four Corners region, northeast New Mexico, and portions of southern Arizona experienced the largest deficits in the past 12 months. The likelihood of an El Niño event continues to offer hope for additional drought relief. There is hope that regular precipitation over the winter may still help saturate soils in the region, which could lead to higher reservoir storage during springtime snowmelt runoff events, even if temperatures stay above average and snowpack is below average, 

Source: High Plains Regional Climate Center - HPRCC

ENSO: Forecast projections range from 65 percent to more than 80 percent probability that an El Niño will occur, with several outlooks indicating an El Niño event is imminent, if not already underway.  The Southwest is experiencing El Niño-like weather patterns and should continue to do so into the spring, especially if the El Niño event is moderate in strength.

Precipitation Forecasts: The Dec. 18 NOAA-Climate Prediction Center seasonal outlook continues to predict above-average precipitation through the winter and into early spring (Fig. 5). This forecast is tied to the ongoing conditions favorable to an El Niño event and the impact of the Pacific Decadal Oscillation.

Temperature Forecasts: The Dec. 18 NOAA-Climate Prediction Center temperature forecasts remain split across the region, with elevated chances for above-average temperatures along the West Coast, extending eastward into Arizona, and with increased chances for below-average temperatures along the Gulf Coast into New Mexico (Fig. 5). This pattern is projected through the winter and into the spring.

Source: NOAA-Climate Prediction Center

Nov 2014 SW Climate Podcast: A Warm End to Autumn and Waiting for ENSO

Wednesday, December 10, 2014

In the November Southwest Climate Podcast, Ben McMahan and Mike Crimmins discuss the warm autumn weather in the southwest, the transition to winter weather patterns, the ongoing uncertainty of El Niño forecasts, a recap of El Niño conditions and definitions, and the possibility of interaction between El Niño conditions and weather patterns in the southwest looking forward.

Intro 0:00
A Wet and Warm Autumn: Warmer than average temps, higher than average humidity, and a recent "cold" snap 1:00
Recap of 2014 Tropical Storm Season: A more active season in the E Pacific 7:30
El Niño Forecast Models: More on how El Niño is defined, models that go into them, and the current state of "now-casting" 13:44
El Niño Definition: Revisiting a more precise definition of El Niño and the conditions we might expect (if it ever arrives) 22:00
Looking toward the Future: Impact of El Niño conditions on the SW, and looking forward into 2015  27:00
Recap on Long Term Forecasts & Looking Forward 34:00

If you have a question you'd like answered, you can email Zack Guido (zguido@email.arizona.edu) or Ben McMahan (bmcmahan@email.arizona.edu) with "CLIMAS Podcast Question" in the subject line. You can also tweet us @CLIMAS_UA or post a question on facebook

Also, as we mentioned last month, we have a new podcast feature: video mini-segments from the podcast.  We have four segments posted from previous podcasts, including:

And we have decided to release approximate transcripts of the podcast.  

Suggested Source/Citation:

CLIMAS: Climate Assessment for the Southwest, (2014). A Warm End to Autumn and Waiting for ENSO. [podcast] CLIMAS Southwest Climate Podcast. Available at: climas.arizona.edu/podcast/nov-2014-sw-climate-podcast-warm-end-autumn-and-waiting-enso [Date Accessed]

What is El Niño? - From the SW Climate Podcast

Monday, December 1, 2014

This mini-segment was taken from the November 2014 Southwest Climate Podcast


Image & Story Credits

El Niño Tracker Update - Late November 2014

Friday, November 21, 2014

From the Nov 20, 2014 Southwest Climate Outlook

The long-awaited El Niño event projected to develop during winter 2014 – 2015 has yet to send a decisive signal regarding an official start, but a number of factors have increased forecasters’ confidence that one will emerge. The strength of this event still remains in question, however with the most likely projection still centering on a weak or weak to moderate event.

On Nov 6, the NOAA-Climate Prediction Center (CPC) issued an El Niño Watch, assigning a 58 percent probability that an El Niño would form and that it most likely would be weak. This forecast was based on a slight increase of sea surface temperatures (SSTs) across the eastern equatorial Pacific, linked to the contribution of the Kelvin wave (discussed last month), which helped warm SSTs in the eastern Pacific.  The CPC also reported the “ongoing lack of clear atmosphere-ocean coupling” (discussed in our previous Southwest Climate Podcasts) reduced confidence in the forecast.  On Nov 18, the Australian Government Board of Meteorology increased its El Niño tracker status from El Niño Watch to El Niño Alert, with a 70 percent probability of an El Niño developing in winter 2014–2015.  This outlook was based on a recent surge in above-average temperatures in the tropical Pacific Ocean (Fig. 1) and the Southern Oscillation Index (Fig. 2), which exceeded the El Niño threshold for the past three months, despite a lack of complete cooperation on the part of atmospheric conditions.

The Nov. 20 International Research Institute for Climate and Society (IRI) and CPC forecast reiterated these points, as the SSTs have exceeded the threshold for weak El Niño conditions, even while some of the atmospheric variables have yet to point towards an El Niño event. The mid-November forecast subsequently upped the probability of El Niño conditions developing to 75 percent (Fig. 3), and the North American multi-model ensemble shows a weak to moderate event peaking in mid to late winter and extending into the spring (Fig. 4).  

The strength of the event, if and when it forms, will matter. The impacts associated with weak El Niño events are generally less certain than those of a moderate or strong event, with past weak events bringing both dry and wet conditions to the Southwest U.S. during the winter. Seasonal precipitation forecasts still indicate an enhanced chance of above-average precipitation over the upcoming winter, but confidence in this forecast is partially contingent on the strength of the emerging El Niño event. It should also be noted that the signal for the Pacific Decadal Oscillation (PDO) has moved into a positive phase, which bodes well for increased precipitation this winter, especially since the El Niño-Southern Oscillation (ENSO) and PDO signals have the potential to enhance, rather than work against, the other.

2014 Pacific Hurricane Season Recap - Focused on the Southwest

Friday, November 21, 2014

From the Nov 20, 2014 Southwest Climate Outlook

The 2014 Pacific hurricane season was the most active season on record since 1992, with 20 named storms (Fig. 1). Fourteen of those storms developed into hurricanes, including eight major hurricanes (category 3 or greater), also breaking a record held since 1992. This meets or exceeds the high end of the NOAA-Climate Prediction Center (CPC) seasonal forecast (May 22), which predicted 14 to 20 named storms, seven to 11 hurricanes, and three to six major hurricanes. The Pacific hurricane forecast was tied to the ongoing El Niño forecast discussion, as conditions linked to the formation of an El Niño event (e.g., decreased wind shear in the tropical Pacific) also favored increased hurricane frequency and intensity in the Pacific region, and it is safe to say this season did not disappoint.  Conversely, the Atlantic hurricane season was relatively quiet, with eight named storms, six of which became hurricanes, including two major ones.  This was also in line with NOAA-CPC projections of seven to 12 named storms, three to six hurricanes, and up to two major hurricanes.

Seasonal Summary and Impact on the Southwest

The season started off strong and early with Hurricane Amanda on May 24 and continued with a number of early season tropical storms and hurricanes. A few early seasons storms, including Amanda, affected portions of Mexico but largely avoided the Southwest U.S. Most followed the typical early season pattern of staying out in the Pacific Ocean.  Notably, Hurricanes Iselle and Julio headed towards the Hawaiian Islands in late July and early August, with only Iselle actually making landfall.  As the season progressed, later season storms followed the expected pattern of recurving back into the Pacific Coast (see additional resources), and a number of major hurricanes, notably Marie, Norbert (with an assist from Atlantic Hurricane Dolly), Odile, and Simon, veered into the Pacific coast and brought considerable moisture into the Southwest. These incursions of rainfall made substantial contributions to the region’s overall monsoon totals; without them, the Southwest likely would be looking at a very different monsoon picture (i.e., below-average precipitation), particularly in September.

Specific Impacts and Looking Forward

In the Southwest, we are accustomed to the seasonal threat of flooding associated with intense monsoon precipitation, but these storms are generally highly variable spatially and relatively short. Hurricane Odile, as it lumbered into the Southwest, presented a unique threat; it had the potential for widespread flooding over a large area and over a number of days. In a worst case scenario, it could have moved slowly across the Tucson region, and dumped six or more inches of rain across the city and Pima County, not to mention additional flood potential from mountain runoff.  

This scenario posed unique challenges for emergency managers tasked with planning and preparing without sensationalizing or inciting fear in the community. Forecasters faced a related challenge of accurately characterizing a storm for which there was limited data available as it moved over data-poor regions of Mexico, knowing that the results of their forecast would be used to make widespread decisions that could prove costly if wrong. The lack of quality data, combined with apprehension about underestimating the threat of Odile, likely contributed to elevated predictions and certain planning decisions. 

Ultimately, Odile swung south of its predicted path by about 70 miles, leading to substantial rain events and considerable flooding in the southeastern corner of Arizona and across portions of southern New Mexico (Fig. 1). Tucson may have avoided the worst-case scenario in terms of hurricane impacts, but lingering effects may be more costly.  The general public derided many of the forecasts as inaccurate or unreliable, saw sensational coverage from outside media sources, and were subject to considerable disruptions associated with school, road, and government closures despite no actual flooding in town. These circumstances may contribute to a decreased likelihood to act on emergency decrees in the near future.

In the coming months, CLIMAS researchers will work with regional planners and officials to further explore the experience of Odile as it relates to emergency management planning and forecasting.

Southwest Climate Outlook November 2014

Thursday, November 20, 2014

From the Nov 20, 2014 Southwest Climate Outlook

Precipitation: Little precipitation fell in Arizona from mid-October to mid-November following the official end of the monsoon on September 30. New Mexico recorded some precipitation of note, mainly in the southeastern corner and in scattered pockets of the central and north-central parts of the state. This is a marked change from monsoon precipitation and the substantial contributions made by the incursions of tropical storms, but this drop-off in rainfall is typical for this time of year; November joins April as one of the driest months for the region.

Temperature: Most of Arizona and New Mexico were warmer than average in the past 30 days, a pattern that was consistent across much of the Southwest. The cold front that brought winter weather to much of the U.S. in mid-November also stretched into the region, but with limited effect and primarily in portions of eastern and southeastern New Mexico. There was a shift towards colder temperatures across the region in the last few days (at time of publication), and while the air feels colder given the previously above average temperatures, the temperatures are close to historical averages. 

Snowpack: Sporadic early winter precipitation resulted in below to above-average snowpack levels across the region. It remains to be seen how much of this early season snowpack will remain, and an above-average snowpack is needed this winter to improve storage in the Upper Colorado and Rio Grande basins. Water Supply: In October, total reservoir storage was 46 percent (compared to 47 percent last year) in Arizona, while total reservoir storage was 22 percent (compared to 21 percent last year) in New Mexico.

Drought: Above-average monsoon precipitation and an active Pacific hurricane season provided some short-term drought relief in the Southwest. Long-term drought relief was limited by the inconsistency of precipitation coverage and the runoff and evaporation associated with high-intensity precipitation events. The likelihood of an El Niño event continues to offer hope for additional drought relief, as these events are typically associated with increased winter precipitation in the region.

ENSO: The latest ENSO projections indicate a 70-75 percent chance that an El Niño event will develop this winter. Some experts believe that conditions are already in place, and that it is only a matter of time before the El Niño event is officially declared. There is less confidence, however, that a moderate to strong event will form and uncertainty about whether a weak event will drive winter precipitation much above average.

Precipitation Forecasts: The NOAA-Climate Prediction Center is calling for elevated chances for above-average precipitation through the winter and into early spring. These predictions are thought to be picking up on both the possibility of an El Niño event this winter and the impact of the Pacific Decadal Oscillation. 

Temperature Forecasts: The NOAA-Climate Prediction Center temperature forecasts are split across the region, with elevated chances for above-average temperatures along the West Coast, extending eastward into Arizona, and with increased chances for below-average temperatures along the Gulf Coast into New Mexico.

Also in this issue:

SW Climate Podcast - Mini-Video: A Tale of Two Tropical Storms - Norbert vs. Odile

Friday, October 24, 2014

Next up in our new series featuring video mini-segments from the podcast.  This segment comes from the September 2014 SW Climate Podcast - and covers the impacts of Norbert and Odile in the Southwest - as part of the 2014 Eastern Pacific Tropical Storm Season

Mike Crimmins and Zack Guido talk about the specific factors that fed into Norbert vs. Odile, as well as the differential impacts of these storms (in Sept 2014).

Taken from the CLIMAS Southwest Climate Podcast

  • Mike Crimmins - CLIMAS: Climate Assessment for the Southwest & University of Arizona Cooperative Extension
  • Zack Guido - University of AZ International Research and Application Program (IRAP)
  • Ben McMahan - CLIMAS: Climate Assessment for the Southwest
  • Emily Huddleston - CLIMAS: Climate Assessment for the Southwest


Image Credits (in order of appearance)

  • Hurricane Norbert off coast of Baja Source: NASA GSFC GOES Satellite
  • Norbert Moisture Incursion - Source: NBC Channel 4 Action News
  • Precipitable Water 9/14/2014 - Source: Cooperative Institute for Meteorological Satellite Studies
  • Space Science and Engineering Center / University of Wisconsin-Madison
  • Hurricane Dolly - Source: First Alert 5 Storm Center (Texas)
  • Norbert Moisture Incursion - Source: Accuweather.com
  • Phoenix Monsoon Rain Plot - Source: Climate Science Applications Program
  • Phoenix Flooding - Source: KSHB
  • Phoenix Flooding - Source AP - Arizona Republic - Michael Chow
  • Odile Projected Path - Source: NBC News
  • Odile Circulation - Source: NASA EOSDIS Worldview
  • Odile Flood Potential - Source: Accuweather.com
  • Odile Flood Potential - Source: Accuweather.com
  • Odile Precip Forecast - Source: NOAA/NWS
  • Odile Track Swing - Source: KVOA Channel 4 News (Jeff Beamish)

If you have a question you'd like answered, you can email Zack Guido (zguido@email.arizona.edu) or Ben McMahan (bmcmahan@email.arizona.edu) with "CLIMAS Podcast Question" in the subject line.  You can also tweet us @CLIMAS_UA or post a question on facebook

Oct 2014 Southwest Climate Podcast: Monsoon Recap & El Niño Double Dips?

Friday, October 24, 2014

In the October Southwest Climate Podcast, CLIMAS climate scientists Zack Guido and Mike Crimmins discuss the 2014 monsoon, focusing on the influence of tropical storm systems, record and near-record precipitation events, monsoon intensity and duration, and the ever-present promise of El Niño.

Intro 0:00
Monsoon/Precipitation Recap: Including influence of tropical storms, record/near-record precipitation, comparison to 2013 1:00
Tropical storm influence: Extending the monsoon and driving seasonal totals 10:00
El Niño Forecast Models: Predicting a wet fall/winter, El Niño influence, Kelvin wave effects and warm waters in the Pacific 15:10
El Niño "Now-Casting": Unique case to watch, why El Niño has been hard to predict 20:00
Drought Mitigation and Winter Precip: - El Niño conditions are favorable and it's almost here  26:00
Recap & Looking Forward: (Arctic Oscillation) 31:30

If you have a question you'd like answered, you can email Zack Guido (zguido@email.arizona.edu) or Ben McMahan (bmcmahan@email.arizona.edu) with "CLIMAS Podcast Question" in the subject line. You can also tweet us @CLIMAS_UA or post a question on facebook

Also, as we mentioned last month, we have a new podcast feature: video mini-segments from the podcast.  We have four segments posted from previous podcasts, including:

Finally, we now have the capacity to release transcripts of the podcast, stay tuned.

SW Climate Podcast - Mini-Video Podcast on El Niño and ENSO Models

Tuesday, October 21, 2014

 

Next up in our new series featuring video mini-segments from the podcast.  This segment comes from the September 2014 SW Climate Podcast - and covers ENSO models and El Niño forecasts.

Mike Crimmins and Zack Guido talk about El Niño forecast models and the way that different metrics are used to predict/forecast an El Niño event.

Taken from the CLIMAS Southwest Climate Podcast

  • Mike Crimmins - CLIMAS: Climate Assessment for the Southwest & University of Arizona Cooperative Extension
  • Zack Guido - University of AZ International Research and Application Program (IRAP)
  • Ben McMahan - CLIMAS: Climate Assessment for the Southwest
  • Emily Huddleston - CLIMAS: Climate Assessment for the Southwest

Image Credits (in order of appearance):

  • Sea Surface Temperature Anomalies - April to December during building El Niño - ​Source: NOAA/Climate.gov
  • Global Sea Surface Anomalies - La Niña (1988) vs El Niño (1997) - Source: NOAA/Climate.gov
  • Ocean SST anomalies during ENSO cycle - Source: http://bobtisdale.wordpress.com
  • Mid-Sept IRI/CPC Plume-Based Probabilistic ENSO Forecast - Source: IRI/CPC
  • April/May/June SST in Pacific Ocean - Source: NOAA/Climate.gov
  • Mid-Sept 2014 Plume of Model ENSO Predictions - Source: IRI/CPC
  • Oceanic Niño Index (ONI) over time - Source: NOAA/CPC
  • El Niño vs. La Niña Winter Patterns  - Source: NOAA

If you have a question you'd like answered, you can email Zack Guido (zguido@email.arizona.edu) or Ben McMahan (bmcmahan@email.arizona.edu) with "CLIMAS Podcast Question" in the subject line.  You can also tweet us @CLIMAS_UA or post a question on facebook

Monsoon Recap - June 15 - Sept 30, 2014

Friday, October 17, 2014

Looking back on the 2014 monsoon, a simple characterization of the season as ‘normal’ or ‘average’ (or above or below these thresholds) is difficult, given the spatial and temporal variability of monsoon storms. The cumulative seasonal totals provide one way of characterizing the monsoon, and by those metrics, the Southwest saw an average to above-average summer rainy season, with much of Arizona and New Mexico receiving well above-average rainfall. 

Most of Arizona received well above-average monsoon rainfall—200 to 400 percent of average—and many     areas in the state registered 150 percent of their seasonal total or higher. The exceptions were across most of the Four Corners region and in portions of Pima, Pinal, and Graham counties (Fig. 1a). Precipitation intensity (Fig. 2a) identifies areas that received a significant portion of their monsoon precipitation in a few extreme events, with the Phoenix metropolitan area and portions of western Arizona being prime examples of more intense precipitation. Figure 3a (the percentage of days observing 0.01 inch of rain or more) further illustrates this pattern by highlighting areas that received more frequent and steady rain (e.g., much of the southeastern portion of the state) compared to areas with much less frequent rain (e.g., Phoenix, western Arizona, and the Four Corners region).

New Mexico saw a similarly strong, if not stronger, monsoon, with most areas of the state receiving more than 200 percent of their seasonal average and large swaths of southern New Mexico recording between 300 and 400 percent of their seasonal average (Fig. 1b). The exceptions were the Four Corners region and the northeastern corner of the state. New Mexico monsoon precipitation intensity (Fig. 2b) shows a relatively even pattern, with more widespread coverage and less variability compared to Arizona. The graphic depicting percent of days with rain in New Mexico (Fig. 3b) shows larger areas of more frequent but less intense precipitation, with a large percentage of the state experiencing measurable precipitation on at least a third of days during the monsoon.

The variability and intensity of these storms is only hinted at in seasonal totals however, and the monsoon is notoriously spatially variable and inconsistent. It is not uncommon for 1–2 inches of rain to fall in midtown Tucson and be dry in the foothills, or vice versa, for example, and many metrics are based on the placement of a limited number of rain gauges. This is an important point because during numerous precipitation events this season, a single storm dropped a season’s worth of rain in a day (and in a few cases, in a few hours), but the coverage was not always consistent or uniform. 

These storms also drive above-average seasonal totals, which has a limited effect on mitigating drought compared to steady and consistent rains, increase disaster potential due to intense precipitation (e.g., Tropical Storm Norbert in Phoenix and Tucson), and underscore the complexity of planning a large urban area for a possible storm event (e.g., Tropical Storm Odile in Tucson). Citizen science enterprises such as rainlog.org provide a more detailed and nuanced picture of monsoon variability through crowdsourcing of precipitation measurement, but the standard measure is still a comparison of the seasonal totals measured at stations in the Southwest (Fig. 4). The intensity and percent of days with rain (Figs. 2-3, above), help illustrate different patterns of steady vs. intense precipitation, but cumulative monsoon precipitation plots also help clarify variation in precipitation intensity.

Three plots (Figs. 5-7) help explain these different types and intensities of rain events. In September, Phoenix (Fig. 5) received almost all of its monsoon precipitation in two single days, and a majority of the rain fell in a single day when Norbert pushed in from the Gulf of California on Sept. 7. The precipitation plot for the Coronado National Monument (Fig. 6) shows a much more even precipitation pattern, with numerous smaller storms spread out over the season; the largest single-day rain event was associated with the incursion of moisture from Odile). The precipitation plot for Tucson (Fig. 7) falls in the middle, with more frequent and smaller storms compared to Phoenix, but longer dry spells and gaps in monsoon precipitation compared to Coronado NM HQ. Norbert is also clearly identifiable in this plot.

This comparison helps illustrate that while extreme precipitation events may provide short-term drought relief and precipitation totals may indicate water deficit improvements, long-term drought conditions will persist and are best mitigated by similarly long-term patterns of above-average precipitation, especially as we look forward to the winter precipitation season.

This post was originally published as part of the October 2014 Southwest Climate Outlook

2014/2015 El Niño Tracker: Oct 16, 2014

Thursday, October 16, 2014

An El Niño Watch, issued by the NOAA Climate Prediction Center (CPC), continues for the seventh consecutive month as signs of an emerging El Niño are just on the horizon, but not quite here yet. Another slug of warm water (also known as a Kelvin wave), has been making its way across the Pacific Ocean from west to east just below the surface and is poised to emerge and help warm sea surface temperatures in the eastern Pacific over the next month or so. Westerly wind bursts, which help move this warmer-than-average water to the east, have occurred in the western and central Pacific but have been temporary and haven’t helped sustain a steady progression towards El Niño conditions, which typically peak during mid-winter. 

Forecast models are betting the current Kelvin wave and associated warm water in the east Pacific will finally get this fickle event to organize and roll forward as a weak El Niño; only a handful of models suggest a moderate-strength event. The early-October consensus forecast (Fig. 1) issued by the International Research Institute for Climate and Society (IRI) and the CPC still indicates more than a 65 percent chance of El Niño conditions developing during the November-December-January period and most likely persisting through early next spring. The impacts associated with weak El Niño events are much less certain than with stronger events, with similar past events bringing both dry and wet conditions to the Southwest U.S. during the winter. Seasonal precipitation forecasts still indicate an enhanced chance of above-average precipitation over the upcoming winter, but confidence in this forecast has wavered slightly because of the expected weak nature of the emerging El Niño. 

This post was originally published as part of the October 2014 Southwest Climate Outlook

SW Climate Podcast - Mini-Video Podcast on Tropical Storm Climatology

Tuesday, October 7, 2014

 

Next up in our new series featuring video mini-segments from the podcast.  This segment comes from the September 2014 SW Climate Podcast - and covers Tropical Storm Climatology in the Southwest.

Mike Crimmins and Zack Guido talk about tropical storm climatology in the southwest, and the various patterns that affect the path of these storms over the season.

Taken from the CLIMAS Southwest Climate Podcast

  • Mike Crimmins - CLIMAS: Climate Assessment for the Southwest & University of Arizona Cooperative Extension
  • Zack Guido - University of AZ International Research and Application Program (IRAP)
  • Ben McMahan - CLIMAS: Climate Assessment for the Southwest
  • Emily Huddleston - CLIMAS: Climate Assessment for the Southwest

Image Credits (in order of appearance)

  • Tropical Storm Point of Origin by Date - Source: NOAA
  • TS Storm Damage - Source: Wikipedia Commons
  • Norbert 2014 Sequence - NASA Worldview Portal
  • TS Storm Frequency - NOAA
  • 2014 Pacific Tropical Storm Tracks - National Weather Service
  • Typical Arizona Cyclone Pattern - National Weather Service Tucson Office
  • Southern Arizona Track Composite - National Weather Service Tucson Office
  • Hurricane Amanda May 26, 2014 - NASA Worldview Portal
  • Genevieve, Iselle, Julio 2014 - NOAA
  • Iselle & Julio - The Weather Channel
  • Iselle Tracker - USA Today
  • Retreat of the Monsoon Ridge - NCEP/NCAR

Academic Credits

  • Ritchie E.A. & K.M. Wood (2011).  The Influence of Eastern Pacific Tropical Cyclone Remnants on the Southwestern United States.  Monthly Weather Review 139, 192-210.

If you have a question you'd like answered, you can email Zack Guido (zguido@email.arizona.edu) or Ben McMahan (bmcmahan@email.arizona.edu) with "CLIMAS Podcast Question" in the subject line.  You can also tweet us @CLIMAS_UA or post a question on facebook

SW Climate Podcast - Mini-Video Podcast on Monsoon & Drought Q&A

Thursday, October 2, 2014

We are introducing a new feature: video mini-segments from the podcast.  The first segment comes from the August 2014 SW Climate Podcast - and addresses monsoon & drought in response to a listener question.

If you have a question you'd like answered, you can email Zack Guido (zguido@email.arizona.edu) or Ben McMahan (bmcmahan@email.arizona.edu) with "CLIMAS Podcast Question" in the subject line.  You can also tweet us @CLIMAS_UA or post a question on facebook

Southwest Climate Podcast: Tropical Storm Climatology & El Niño Models

Wednesday, October 1, 2014

In the September Southwest Climate Podcast, Zack Guido and Mike Crimmins talk about tropical storm climatology, details about Norbert and Odile, explore the details of the "Kelvin Wave", and answer a question about El Niño models submitted by a listener.

Intro & Recap: 0:00
Tropical Storm Climatology 10:06
Norbert Vs. Odile 14:45
What is a Kelvin Wave? 27:53
El Niño Models (Question from listener) 29:45

If you have a question you'd like answered, you can email Zack Guido (zguido@email.arizona.edu) or Ben McMahan (bmcmahan@email.arizona.edu) with "CLIMAS Podcast Question" in the subject line.  You can also tweet us @CLIMAS_UA or post a question on facebook

Also, we are introducing a new feature: video mini-segments from the podcast.  The first of which comes from last month's podcast, and addresses monsoon & drought in response to a listener question, and is viewable on youtube.

 

Monsoon Summary (June 15 – Sep 18)

Friday, September 19, 2014

We are nearing the end of the 2014 season, and while it is difficult to characterize the highly variable day-to-day storms of any monsoon as “normal,” we have had a fairly typical if not above-average monsoon season in terms of precipitation. Regional assessment is complicated by the effects of a few extreme events that amplified precipitation amounts in parts of Arizona and New Mexico and caused an entire month’s or year’s worth of precipitation to fall in a single storm.

Southeast, southern, west-central, and the high-elevation areas of central Arizona have all seen impressive monsoon totals, with precipitation ranging from 200 to 400 percent of average. Most of Arizona, in fact, has seen above-average seasonal monsoon precipitation (100-200 percent of average) with the exception of the Four Corners region, which is struggling with below-average precipitation and long-term drought (Figure 1). The intensity of these storms, measured as the ratio of total precipitation over the time period to the number of days observing rain, in inches per day (Figure 2), reveals that some areas—western Arizona in particular—received a significant portion of their monsoon precipitation in a few extreme events, and in some cases a single storm. These intense storms offer little in the way of long-term drought relief but pose major threats in terms of their destructive potential, especially in urban/metropolitan areas. Figure 3 (the percentage of days observing 0.01 inch or more) illustrates which areas received more consistent and steady rain.

New Mexico has seen a strong monsoon as well, with most of the state receiving well-above-average precipitation, and large portions of central and southern New Mexico receiving 200 percent or greater of average precipitation. As with Arizona, the Four Corners region is below average, as is the northeastern corner of the state (Figure 4). Maps of the intensity and frequency of monsoon precipitation in New Mexico (Figures 5 and 6, respectively) show larger areas of more frequent, less intense storms. This precipitation should help mitigate short-term drought conditions, but long-term deficits remain.

Tropical storms have been active in the Pacific, and while early-season storms veered into the Pacific Ocean, recent storms (Marie, Norbert, and Odile) have followed the later-season pattern of re-curve into the Pacific coast, boosting precipitation in the Southwest (albeit in a highly variable way). Norbert caused considerable flooding in Phoenix and to a lesser extent in Tucson, and on September 17 Odile caused most of southern Arizona and New Mexico to brace for the worst, with projections of 3-6 inches of rain for those in the direct path. The storm eventually swung south, and most of the impacts were felt in northern Mexico and far-southern Arizona (Figure 7).

This post was originally published as part of the September 2014 Southwest Climate Outlook

El Niño Tracker - Sept 2014

Thursday, September 18, 2014

The song remains the same this month with El Niño not quite here yet, but probably soon. This is now the seventh consecutive month since the NOAA Climate Prediction Center issued an “El Niño Watch” last March. The signs are a bit stronger once again, but it is getting late in the game since El Niño events take several months to build up and typically peak during the mid-winter months. Another slug of warm water (known as a “Kelvin Wave”) has been making its way across the Pacific Ocean from west to east just below the surface and is poised to emerge and help warm sea-surface temperatures in the eastern Pacific over the next month or so. There has also been some activity in the western and central Pacific called “westerly wind bursts” which can help move this warmer-than-average water to the east, but the bursts have been temporary and haven’t helped sustain a steady progression towards El Niño conditions. 

Forecasts models are predicting the current Kelvin Wave and associated warm water in the east Pacific will finally get this fickle event to organize and roll forward as at least a weak El Niño. The mid-September consensus forecast (Figure 1) issued by the International Research Institute for Climate and Society (IRI) and the NOAA Climate Prediction Center (NOAA-CPC) still indicate a greater than 70 percent chance of El Niño conditions developing during the November-December-January period and most likely persisting through early next spring. Most models indicate that the event will ultimately peak at a weak strength, with only a handful of models suggesting a moderate-strength event. The impacts associated with weak El Niño events are much less certain; past events have brought both dry and wet conditions to the southwest U.S. during the winter season. Seasonal precipitation forecasts still indicate an enhanced chance of above-average precipitation over the upcoming winter season, but confidence in this forecast has wavered slightly because of the expected weak nature of the emerging El Niño event.

This post was originally published as part of the September 2014 Southwest Climate Outlook

Southwest Climate Podcast: Monsoon Frequency vs. Intensity, & El Niño Still Dragging its Heels

Tuesday, August 26, 2014

In the August Southwest Climate Podcast, Zack Guido and Mike Crimmins talk about variability and timing of monsoon precipitation, and why frequent and sustained moisture might matter more than heavy infrequent rains (for drought, especially).  El Niño is still dragging its heels, but it still looks good for a weak to moderate event this winter.  Interspersed throughout, Zack and Mike answer questions submitted by listeners, including "weather" vs. "climate" and how the monsoon is a good way to think about this distinction, and whether the monsoon and El Niño can really help with a long term drought.  

If you have a question you'd like answered, you can email Zack Guido (zguido@email.arizona.edu) or Ben McMahan (bmcmahan@email.arizona.edu) with "CLIMAS Podcast Question" in the subject line.  You can also tweet us @CLIMAS_UA or post a question on facebook

 

Monsoon Summary (June 15 - Aug 19)

Friday, August 22, 2014

The 2014 monsoon can be characterized many ways—the amount and intensity of rain has been spotty both spatially and temporally, the humidity has been persistently high, and precipitation has improved short-term drought conditions in many areas. Certainly it cannot be characterized as a dud. 

With about a month remaining in the 2014 monsoon season, southeast Arizona, the higher elevation areas in central Arizona, and west-central Arizona have generally experienced above-average precipitation (Figure 1). West-central Arizona historically experiences less monsoon rainfall and more infrequent storms then other regions, and this year only a few storms have generated most of the observed rainfall in this region. Consequently, west-central Arizona boasts higher storm intensity, a metric that takes the total accumulated precipitation and divides it by the number of days with precipitation. Using this metric, west-central Arizona has an intensity of 0.5 inches per day; many of the higher elevation regions also have a similar intensity, where as the desert values are less than 0.2 inches per day. A notable exception occurs around Phoenix where 2–3 inches of rainfall fell on August 19 (with some nearby stations tallying as much as 5–6 inches) and caused severe flash flooding. In New Mexico, precipitation has been above average across most of the state and in particular within the Rio Grande basin (Figure 2). Consequently, short-term drought conditions have improved in recent weeks, although water storage is still low from the accumulated impacts of below-average winter rain and snow over the last decade. 

The frequency of rain tells another story and shifts the focus to southeastern Arizona. In this region, precipitation greater than 0.1 inches has fallen during half of the days since June 15 (Figure 3). Most rain gauges in this region have measured near-average or above-average precipitation. Monsoon storms have also been frequent in New Mexico, with most of the state experiencing rainfall on half of the days since June 15 (Figure 4). 

Tropical storm activity in the eastern Pacific Ocean has also been active, although all eight of the named cyclones have tracked westward away from the North American continent. Hurricane activity is expected to continue through October; this could bring even more moisture to the Southwest, as some of the biggest floods on record have occurred from decaying tropical storms wafting over the region.  

This post was originally published as part of the August 2014 Southwest Climate Outlook

El Niño Watch - Aug 21, 2014

Thursday, August 21, 2014

An “El Niño Watch” continues this month as issued by the NOAA Climate Prediction Center several months ago. The watch is just that: we are waiting and watching for the development of a full-fledged El Niño event that has yet to materialize across the equatorial Pacific Ocean. Several indicators of El Nino-Southern Oscillation (ENSO) status declined, moving back towards ENSO-neutral values over the past month instead of leaning towards an El Niño event as they had been.  These shifts included slight cooling in the eastern Pacific Ocean and near-average wind patterns along the equator (Figure 1). But for those cheering on the development of an El Niño event, not all hope is lost. A slug of warm water just below the surface has materialized in the western Pacific Ocean and is slowly moving eastward.  This is similar to the pulse of warm water that led to dramatic warming in the eastern Pacific Ocean earlier this spring. This “Kelvin Wave” is not as strong in magnitude as the earlier springtime wave, but is expected to surface in the eastern Pacific over the next several months, pouring fuel back into the El Niño engine.

Seasonal ENSO outlooks pick up on this pattern and remain rather bullish in suggesting that an El Niño event is likely later this fall that would peak in early winter (Figure 2). The models suggest this would be a moderate event at best; in fact most models suggest a weak El Niño event of around 1 degree C above average in sea-surface temperatures in the central/eastern Pacific Ocean. The weaker the event, the trickier the forecast with respect to expected precipitation across Arizona and New Mexico. Weak El Niño events vary between wet, near average, and even dry winters in historical records across the Southwest. Official seasonal precipitation forecasts continue to suggest an enhanced chance of above-average precipitation across Arizona and New Mexico through the winter, but confidence in these forecasts is tied to the development and ultimate strength of the El Niño event that has yet to materialize.

This post was originally published as part of the August 2014 Southwest Climate Outlook

Recap: Drought and Water Supplies in the Southwest - 1075' Shortage on the Colorado River

Wednesday, August 13, 2014

This week, we released the 5th episode in the CLIMAS podcast series[1] 1075' - Shortage on the Colorado River, which explores what a shortage declaration on the Colorado River would mean to those living in the Southwest. 1075 refers to the elevation of Lake Mead – in feet above sea level – that serves as the trigger for shared shortage restrictions[2].   Any shortage declaration before 2026 would be the first under the 2007 Interim Guidelines[3].  After years of drought and ever-increasing demands on the river, the latest projections from the Bureau of Reclamation suggest the lake could drop below 1075 sometime in  2015.  

Water availability and potential shortages are a persistent concern for the Southwest, and careful management and creative conservation efforts are a requisite part of a sustainable water use plan for the region.  We knew this was a timely and relevant issue when we planned and recorded the series over spring and summer 2014, but we didn't anticipate the media frenzy that led to more sensationalistic media coverage of Lake Mead levels specifically, and water issues in the west more generally.

The media attention reinforced our goal of "attempting to demystify the rules and regulations that govern water use on the Colorado River and discuss what it means to the people and sectors across Arizona when a shortage occurs..." and of "exploring the opportunities and consequences of a shortage to construct a nuanced view of a complex issue."  The negative side is often what receives the most attention. But, perhaps a shortage will spur innovation and lead to better conservation that saves money. At the most fundamental level, we wanted to know if Lake Mead falling below 1075 would be looked back upon as a moment in history that 'changed everything' or if this seemingly inevitable moment would feel a lot like the Y2K craze.

We turned to regional water experts to help us better understand Southwest water supply issues, the Central Arizona Project, realities of water management, opportunities for conservation, and details on what will actually happen if - and more likely when - a shortage declaration is made in the next few years.

Episodes

  • In Episode 1: Management of the Colorado River, Zack Guido and Ryan Thomas interview Doug Kenney about the management and history of the Colorado River, who uses the water, and what a potential shortage could mean for the system.  This is an excellent and detailed overview of Colorado River management issues, and is an excellent foundation for subsequent episodes.
  • In Episode 2: Stressors on the River, Zack sits down with Bonnie Colby, Geroge Frisvold, and Kiyomi Morino to discuss specific stressors on the Colorado River Basin, how these stressors may change over time, and how these changes may affect management and behaviors across the Southwest.
  • In Episode 3: Shortage Impacts on the Central Arizona Project, Zack and Ryan are joined by Mohammed Mahmoud of the Central Arizona Project (CAP) to the role that CAP plays in delivering Colorado River water throughout Arizona, as well as implications for the CAP system if/when a shortage declaration is made.
  • In Episode 4: The Central Arizona Groundwater Replenishment District Zack interviews Dennis Rule of the Central Arizona Groundwater Replenishment District (CAGRD), to get into details about the CAGRD in the management of Arizona groundwater, and potential impacts on the system from continued drought in the Colorado River Basin.
  • In Episode 5: Tucson Water and Municipal Water Issues Zack sits down with Alan Forrest, the Director of Tucson Water, and they discuss strategies that Tucson implemented to deal with potential water shortages, the conservation and recapture efforts of municipalities in Southern Arizona, and the practical realities of providing municipal water to an growing population in the southwest.

Background

These issues (Lake Mead levels, water management concerns, etc.) didn't pop up out of nowhere.  The social, environmental, and management context are the backstory - and the experts we interviewed helped us capture some of the nuance, but it's also important to highlight a few threads that contributed to the ongoing conversation.

Stories and reports about drought conditions, especially in California and Texas, brought contemporary water issues to the forefront over the past year or so [4].  Attention ramped up this spring and summer as media outlets picked up in on a new study highlighting higher than predicted groundwater consumption estimates, especially in the southwest (see this map).  Media coverage focused on this story, as well as the drop in water levels at Lake Mead, often conflating groundwater and surface/allocation water issues.  Coverage veered into the sensational, as stark images of dry conditions dominated the coverage, while the headlines were filled with portents of doom.  The added attention can help bring energy and ideas to critical issues in need of timely solutions, but it can also confuse audiences when they see headlines predicting societal and environmental collapse.  These problems persist long after media attention has waned, and managers must respond to the aftermath of this style of coverage, focusing on practical solutions and maintaining good working relationships with a diverse network of stakeholders (some of whom are alienated from the process by overly binary or simplistic pronouncements of any political flavor).

As is often the case, this wasn't even the first time this had been written about in detail, and a number of journalists and scientists have been giving this issue careful consideration as it unfolds.  John Fleck has been tracking this issue in detail, and has a number of insightful posts (Lower CO Basin New Years Resolution - 2012 - The Colorado River Doomsday Clock - 2013), including a one earlier this summer detailing CAP strategies for management, and his most recent entry addressing specific challenges (and possible implications) of the results outlined in the Castle et al. study.  Fleck also wrote about policy implications for this study, detailing flexibility in the Colorado River System thus far, as well as how groundwater usage complicates management plans and outcomes.  Brian Devine wrote about the consequences of agricultural to municipal water transfers, as well as more general questions about conservation, and Doug Kenney and Kimery Wiltshire used the record low level in Lake Mead to frame a discussion of implications for shortages and strategies for management and conservation.

The point? - a number of people have been thinking about this for a long time - and we hope that by turning to a few of these experts, both in the framing of why we did this podcast, and who we were able to bring in for conversations, we can present a nuanced take on the very real challenge of water management in the Southwest, but without losing sight of the strategies that have worked and are working to protect this limited resource.  Stay tuned - we plan to expand this conversation to include additional perspectives on this issue.

Notes

  1. We may do a second "season" given all the interest in the series, especially since there are numerous other experts we would love to talk to, and other sectors (e.g. ranching, agricultural, industrial) that we would like to include in the conversation.
  2. Note: Mead elevation falling below 1075' in a given month does not automatically trigger shortage restrictions. The January 1st forecast from the August 24-month study is the Mead elevation value that determines if a Tier 1 Lower Basin shortage will occur. The 24-month study is a monthly report produced by the Bureau of Reclamation to keep track of Colorado River system reservoirs. So even if Lake Mead is forecasted to drop below 1075' in mid-2015, shortage is not declared unless the 2014 August 24-month study forecasts a January 1st Mead elevation at or below 1075'.
  3. There was a shortage declared in 1963/1964 when Lake Powell was filling. Drought caused low inflows into Lake Mead and deliveries to the Lower Basin were subsequently cut.  
  4. There was some hope that a stronger El Niño might alleviate some of the drought conditions, but as predictions for a strong El Niño event have waned, so has that optimism.

Many thanks to Dr. Mohammed Mahmoud (of the Colorado River Programs / Central Arizona Project) for providing the clarifications in footnotes [2-3].

1075' - Shortage on the Colorado River Ep. 5 - Tucson Water & Muncipal Water Issues

Tuesday, August 12, 2014

Lake Mead from the Hoover Dam - Source: Wikipedia Commons

1075’ – Shortage on the Colorado River is a CLIMAS podcast series that explores what the first ever shortage declaration on the Colorado River would mean to those living in the Southwest. 

1075 refers to the elevation of Lake Mead – in feet above sea level – that serves as the trigger for shared shortage restrictions[1]. While this has never happened before[2], after years of drought and ever-increasing demands on the river, the latest projections from the Bureau of Reclamation suggest the lake could drop below 1075[3] as soon as early 2015.

In this series, we attempt to demystify the rules and regulations that govern water use on the Colorado River and discuss what it means to the people and sectors across Arizona when a shortage occurs. This series will explore the opportunities and consequences of a shortage to construct a nuanced view of a complex issue.

  • Episode 5: Tucson Water and Municipal Water Issues (Alan Forrest) - In this episode, CLIMAS climate scientist Zack Guido speaks with Alan Forrest, Director of Tucson Water, about various strategies that Tucson implemented to deal with potential water shortages, the conservation and recapture efforts that areas of municipalities in Southern Arizona, and the practical realities of providing municipal water to an growing population in the southwest.

 


Alan Forrest is Director of Tucson Water, a municipally owned water utility serving a population of over 700,000 (250,000+ services) in the Tucson and Pima County Area in SE Arizona.  He is one of Arizona's recognized experts in water management, and began his municipal water career at Tucson Water in the 1980's.  He has worked on water and municipal water issues in Southern Arizona for over 30 years, in both the public and private sectors.


[1] Note: Mead elevation falling below 1075' in a given month does not automatically trigger shortage restrictions. The January 1st forecast from the August 24-month study is the Mead elevation value that determines if a Tier 1 Lower Basin shortage will occur. The 24-month study is a monthly report produced by the Bureau of Reclamation to keep track of Colorado River system reservoirs. So even if Lake Mead is forecasted to drop below 1075' in mid-2015, shortage is not declared unless the 2014 August 24-month study forecasts a January 1st Mead elevation at or below 1075'.

[2] Any shortage before 2026 would be the first declared shortage under the 2007 Interim Guidelines. However, there was a shortage declared in 1963/1964 when Lake Powell was filling up. Drought caused low inflows into Lake Mead and deliveries to the Lower Basin were subsequently cut.

[3] The Applied Climate Science Group in the School of Natural Resources at the University of Nebraska-Lincoln has compiled an impressive array of photos and data relating to the drop in Lake Mead levels - be sure to check it out!

Many thanks to Dr. Mohammed Mahmoud (of the Colorado River Programs / Central Arizona Project) for providing the clarifications in footnotes [1] and [2].

1075' - Shortage on the Colorado River Ep. 4 - CAGRD (Dennis Rule)

Tuesday, August 5, 2014

Lake Mead from the Hoover Dam - Source: Wikipedia Commons

1075’ – Shortage on the Colorado River is a CLIMAS podcast series that explores what the first ever shortage declaration on the Colorado River would mean to those living in the Southwest. 

1075 refers to the elevation of Lake Mead – in feet above sea level – that serves as the trigger for shared shortage restrictions[1]. While this has never happened before[2], after years of drought and ever-increasing demands on the river, the latest projections from the Bureau of Reclamation suggest the lake could drop below 1075[3] as soon as early 2015.

In this series, we attempt to demystify the rules and regulations that govern water use on the Colorado River and discuss what it means to the people and sectors across Arizona when a shortage occurs. This series will explore the opportunities and consequences of a shortage to construct a nuanced view of a complex issue.

  • Episode 4: The Central Arizona Groundwater Replenishment District (Dennis Rule) - In this episode, CLIMAS climate scientist Zack Guido talks to Dennis Rule, manager of the Central Arizona Groundwater Replenishment District (CAGRD), about the importance of CAGRD in the management of Arizona groundwater and potential impacts on the system from continued drought in the Colorado River Basin.

 


Dennis Rule is the Manager of the Central Arizona Groundwater Replenishment District (CAGRD).  In 1993, the legislature created a groundwater replenishment authority to be operated by the Central Arizona Water Conservation District ("CAWCD") throughout its three-county service area. This replenishment authority of CAWCD is commonly referred to as the Central Arizona Groundwater Replenishment District ("CAGRD"). In 1999, the legislature expanded CAWCD's replenishment authorities and responsibilities by passing the Water Sufficiency and Availability Act. The purpose of the CAGRD is to provide a mechanism for landowners and water providers to demonstrate an assured water supply under the new Assured Water Supply Rules ("AWS Rules") which became effective in 1995. Every ten years, the CAGRD is required by law to submit a Plan of Operation to the Director of ADWR. The Plan describes the activities that CAGRD proposes to undertake in the Phoenix, Pinal and Tucson Active Management Areas ("AMAs") over the next one-hundred years based on continued membership enrollment through 2015.


[1] Note: Mead elevation falling below 1075' in a given month does not automatically trigger shortage restrictions. The January 1st forecast from the August 24-month study is the Mead elevation value that determines if a Tier 1 Lower Basin shortage will occur. The 24-month study is a monthly report produced by the Bureau of Reclamation to keep track of Colorado River system reservoirs. So even if Lake Mead is forecasted to drop below 1075' in mid-2015, shortage is not declared unless the 2014 August 24-month study forecasts a January 1st Mead elevation at or below 1075'.

[2] Any shortage before 2026 would be the first declared shortage under the 2007 Interim Guidelines. However, there was a shortage declared in 1963/1964 when Lake Powell was filling up. Drought caused low inflows into Lake Mead and deliveries to the Lower Basin were subsequently cut.

[3] The Applied Climate Science Group in the School of Natural Resources at the University of Nebraska-Lincoln has compiled an impressive array of photos and data relating to the drop in Lake Mead levels - be sure to check it out!

Many thanks to Dr. Mohammed Mahmoud (of the Colorado River Programs / Central Arizona Project) for providing the clarifications in footnotes [1] and [2].

1075' - Shortage on the Colorado River Ep. 3 - Shortage Impacts on the CAP

Tuesday, July 29, 2014

Lake Mead from the Hoover Dam - Source: Wikipedia Commons

1075’ – Shortage on the Colorado River is a CLIMAS podcast series that explores what the first ever shortage declaration on the Colorado River would mean to those living in the Southwest. 

1075 refers to the elevation of Lake Mead – in feet above sea level – that serves as the trigger for shared shortage restrictions[1]. While this has never happened before[2], after years of drought and ever-increasing demands on the river, the latest projections from the Bureau of Reclamation suggest the lake could drop below 1075[3] as soon as early 2015.

In this series, we attempt to demystify the rules and regulations that govern water use on the Colorado River and discuss what it means to the people and sectors across Arizona when a shortage occurs. This series will explore the opportunities and consequences of a shortage to construct a nuanced view of a complex issue.

  • Episode 3: Shortage Impacts on the Central Arizona Project (Mohammed Mahmoud) - In this episode, CLIMAS climate scientist Zack Guido and Mohammed Mahmoud, planning analyst with the Colorado River Programs department at the Central Arizona Project (CAP), discuss the CAP and its role in delivering Colorado River water throughout Arizona, as well as how a shortage would impact the CAP system.

 


Mohammed Mahmoud is a Planning Analyst II with the Colorado River Programs department at the Central Arizona Project. His educational background includes a B.S. (2001) and M.S. (2003) in Civil Engineering from Michigan Technological University, and a PhD (2008) in Hydrology and Water Resources from the University of Arizona. Mohammed's primary area of expertise is future planning; especially as related to scenario development for decision-making needs. In his doctoral research, Mohammed developed a formal framework for scenario development aimed at enhancing water resources decision-making. At CAP, Mohammed is engaged in Colorado River water policy issues, climate change activities, and the modeling of water uses within the Colorado River.


[1] Note: Mead elevation falling below 1075' in a given month does not automatically trigger shortage restrictions. The January 1st forecast from the August 24-month study is the Mead elevation value that determines if a Tier 1 Lower Basin shortage will occur. The 24-month study is a monthly report produced by the Bureau of Reclamation to keep track of Colorado River system reservoirs. So even if Lake Mead is forecasted to drop below 1075' in mid-2015, shortage is not declared unless the 2014 August 24-month study forecasts a January 1st Mead elevation at or below 1075'.

[2] Any shortage before 2026 would be the first declared shortage under the 2007 Interim Guidelines. However, there was a shortage declared in 1963/1964 when Lake Powell was filling up. Drought caused low inflows into Lake Mead and deliveries to the Lower Basin were subsequently cut.

[3] The Applied Climate Science Group in the School of Natural Resources at the University of Nebraska-Lincoln has compiled an impressive array of photos and data relating to the drop in Lake Mead levels - be sure to check it out!

Many thanks to Dr. Mohammed Mahmoud (of the Colorado River Programs / Central Arizona Project) for providing the clarifications in footnotes [1] and [2].

Southwest Climate Podcast: Strong Start for the Monsoon & Groundhog Day for El Niño Forecasts

Thursday, July 24, 2014

In the July Southwest Climate Podcast, CLIMAS climate scientists Zack Guido and Mike Crimmins talk about the solid start to the monsoon, and seemingly inevitable monsoon breaks (like we just experienced). They also discuss the "inevitability" of this fickle El Niño event. There’s a feeling of Groundhog Day with these forecasts—and there continues to be uncertainty regarding the strength and duration of this El Niño event.

 

 

1075' - Shortage on the Colorado River - Podcast Ep. 2 - Stressors on the River

Tuesday, July 22, 2014

Lake Mead from the Hoover Dam - Source: Wikipedia Commons

1075’ – Shortage on the Colorado River is a CLIMAS podcast series that explores what the first ever shortage declaration on the Colorado River would mean to those living in the Southwest. 

1075 refers to the elevation of Lake Mead – in feet above sea level – that serves as the trigger for shared shortage restrictions[1]. While this has never happened before[2], after years of drought and ever-increasing demands on the river, the latest projections from the Bureau of Reclamation suggest the lake could drop below 1075[3] as soon as early 2015.

In this series, we attempt to demystify the rules and regulations that govern water use on the Colorado River and discuss what it means to the people and sectors across Arizona when a shortage occurs. This series will explore the opportunities and consequences of a shortage to construct a nuanced view of a complex issue.

  • Episode 2: Stressors on the River (B. Colby, G. Frisvold, K. Morino) In this episode, CLIMAS climate scientist Zack Guido hosts three University of Arizona experts, Bonnie Colby, George Frisvold and Kiyomi Morino, to discuss water supply and demand in the Colorado River basin. This podcast explores stressors on the Colorado River Basin, how these stressors may change over time, and how these changes may affect management and behaviors across the Southwest.

Bonnie Colby is a professor in the UA Department of Agricultural and Resource Economics.  Some of her current projects involve nonmarket valuation of natural amenities, analyzing transactions costs generated by regulatory policies, evaluating the reallocation of water resources among economic sectors, economic tools to resolve environmental conflicts, and identifying strategies to promote efficient allocation of risk associated with variability in water supply and water quality.

George Frisvold is a professor in the UA Department of Agricultural and Resource Economics.  His research interests include the economics of climate change adaptation and mitigation, water resources, renewable energy, agricultural R&D, technology adoption, and agricultural biotechnology.

Kiyomi Morino is a research associate in the UA Laboratory of Tree-Ring Research.  Her research is focused on integrating science and policy, particularly with respect to western water issues, and she is working with colleagues to develop novel ways of exploring future climate change impacts on the Colorado River using tree-ring based reconstructions of streamflow. 


[1] Note: Mead elevation falling below 1075' in a given month does not automatically trigger shortage restrictions. The January 1st forecast from the August 24-month study is the Mead elevation value that determines if a Tier 1 Lower Basin shortage will occur. The 24-month study is a monthly report produced by the Bureau of Reclamation to keep track of Colorado River system reservoirs. So even if Lake Mead is forecasted to drop below 1075' in mid-2015, shortage is not declared unless the 2014 August 24-month study forecasts a January 1st Mead elevation at or below 1075'.

[2] Any shortage before 2026 would be the first declared shortage under the 2007 Interim Guidelines. However, there was a shortage declared in 1963/1964 when Lake Powell was filling up. Drought caused low inflows into Lake Mead and deliveries to the Lower Basin were subsequently cut.

[3] The Applied Climate Science Group in the School of Natural Resources at the University of Nebraska-Lincoln has compiled an impressive array of photos and data relating to the drop in Lake Mead levels - be sure to check it out!

Many thanks to Dr. Mohammed Mahmoud (of the Colorado River Programs / Central Arizona Project) for providing the clarifications in footnotes [1] and [2].

Monsoon Summary (June 15 - July 15)

Friday, July 18, 2014

Originally published in the Southwest Climate Outlook, released the 3rd Thursday of every month.  Sign up for email newsletter version.


Monsoon storms began around July 3 in many parts of southern Arizona. The average onset date of the monsoon in southeast Arizona is between July 1 and 6 (Figure 1). In months that preceded the monsoon, climatologists speculated that a developing El Niño event could delay the onset, an interpretation based on past analogs. This did not occur, in part because the atmosphere has yet to respond to the El Niño, despite warmer-than-average sea surface temperatures (SSTs) in the tropical Pacific Ocean (see El Niño Watch for details). 

Many parts of Arizona received above-average precipitation last month thanks to monsoon rainfall (Figure 2). The spotty nature of the monsoon, however, belies sweeping characterizations that apply to all regions because above- and below-average rainfall is often experienced over short distances not captured by more sparsely located rain gauges. The Prescott area of Arizona, for example, has not yet been doused as much as other areas. Nonetheless, many weather stations in southeastern Arizona have measured above-average rainfall since June 15. These include the Tucson International Airport and airports in Douglas and Nogales, where rain has measured 1.61, 2.59, and 3.4 inches since June 15, respectively. These totals amount to 0.45, 1.01, and 1.14 inches above average, respectively. Sierra Vista logged 4.87 inches of rain—3.36 inches above average. 

Many places around Arizona have felt above-average humidity. This is reflected in dewpoint temperatures, which increase as moisture content in the air increases, across the state. In Tucson, for example, dewpoints often have been above 60 degrees F (Figure 3), as they have in Phoenix and Yuma. These humidity levels indicate that moisture is present and, if other conditions converge, storms will result. The intensity and geographic coverage of the storms, however, also depend in part on atmospheric temperature gradients that enable air to rise, condense, and squeeze out rain, and on the presence of winds aloft that push storms off the mountains. Even if rain does not fall, higher levels of humidity help suppress fire risk, and fire restrictions across the regions are being eased.

While southern Arizona generally has experienced an active monsoon thus far, the opposite story has evolved in southern New Mexico and southwest Texas (Figure 2). El Paso, for example, has only received 0.32 inches of rain, or about 0.8 inches below average. The position of the high pressure system, which has largely been centered north of southeast Arizona, has helped create this juxtaposition. On the western, Arizona side of the system, moisture-laden air has been streaming from the south, whereas dry air has been wafting from the north on the eastern, New Mexican side.

El Niño Watch - July 18, 2014

Friday, July 18, 2014

Originally published in the Southwest Climate Outlook, released the 3rd Thursday of every month.  Sign up for email newsletter version.


The El Niño event that has been anticipated for the past several months continues to suffer from stage fright; it has yet to fully materialize across the equatorial Pacific Ocean. Nonetheless, forecasts remain bullish that an El Niño will form in coming months, and consequently the El Niño Watch is still in place. Probabilities that an El Niño will fully materialize this fall and winter reach slightly more than 70 percent, according to the mid-July ENSO forecast issued by the NOAA-Climate Prediction Center (CPC) and the International Research Institute for Climate and Society (IRI; Figure 1). These high probabilities reflect above-average sea surface temperatures (SSTS) in the far eastern Pacific and weak westerly winds in the central Pacific. Belief that this event will evolve into a strong El Niño, however, has lost muster because SSTs have hovered slightly above average and not steadily climbed (Figure 2). In addition, the atmosphere has failed to cooperate in a manner consistent with above-average SSTs. For an El Niño to gain strength, the warming SSTs in the central Pacific need to be accompanied by a subsequent weakening of the easterly trade winds which, in turn, reinforce warm SSTs. The easterly winds have yet to slacken as much as expected.

Nonetheless, the CPC forecast suggests that both the ocean and atmosphere are transitioning to and ultimately will become an El Niño. Feeding this expectation is the observation that convection in the central Pacific has become more organized in recent weeks. This indicates a growing atmospheric connection with the SSTs that could eventually lead to a weakening of the trade winds. Moreover, many of the dynamical forecast models (those that included both ocean and atmosphere dynamics) suggest a rapid warming in the central Pacific during the August–October period, with the El Niño event peaking in mid-winter of 2014 and 2015. Although the ultimate strength and duration remains uncertain, a weak to moderate event appears the most likely outcome, and the CPC notes the possibility for a strong event has diminished greatly in the past several months.

El Niño events tend to bring wetter conditions to the Southwest during the winter (Figure 3), with moderate and strong events delivering higher chances for above-average precipitation. However, if the El Niño event is weak, the precipitation outlook for the upcoming fall and winter becomes more uncertain. The strength and duration of the event should become clearer over the next two months as ocean and atmosphere signals lock in to each other.

Southwest Climate Outlook July 2014

Friday, July 18, 2014

Originally published in the Southwest Climate Outlook, released the 3rd Thursday of every month.  Sign up for email newsletter version.


Precipitation: June was very dry, with little to no precipitation save for remnant moisture from Hurricane Cristina. An on-time start to the monsoon led to above-average precipitation in the first two weeks of July in parts of Arizona and New Mexico. Since mid-January, most of Arizona and New Mexico have logged less than 50 percent of average precipitation.

Temperature: Most of Arizona and New Mexico were warmer than average in June. The onset of the monsoon around July 3 has driven lower-than-average temperatures across the region.

Water Supply: Total reservoir storage increased by about 1.2 million acre-feet (AF) in Arizona in June. Lake Powell rose by about 1.8 million AF and Lake Mead fell by about 394,000 AF. Storage stands at 47 percent of capacity in Arizona and is lower than it was one year ago (49 percent). In New Mexico, storage decreased by 127,000 AF in June, mostly due to a 137,000 acre-foot drop at Elephant Butte. Storage in New Mexico stands at 23 percent of capacity and is greater than it was one year ago (17 percent). (AZ Reservoir Volumes / NM Reservoir Volumes)

Drought: Moderate to extreme drought continues to cover nearly all of Arizona. More than 72 percent of the state is classified with severe drought while extreme drought covers about 16 percent of the state. Almost all of New Mexico is under moderate to exceptional drought (the highest category), with more than 77 percent of the state designated as severe and over 40 percent designated as extreme drought.

Monsoon: Monsoon storms began in southeastern Arizona around July 3, falling within the historical average onset date range. Precipitation since July 1 has been above average in many parts of southern Arizona but generally below average in southern New Mexico. (monsoon summary - July SW Climate Outlook)

Fire Summary: Between January 1 and July 14, 1,074 wildfires burned 157,497 acres in Arizona and 551 wildfires scorched 20,675 acres in New Mexico. The monsoon has brought much needed moisture and humidity to the region. 

ENSO: ENSO-neutral conditions continue. The probability that an El Niño event will develop is 70 percent, increasing to 80 percent in fall and winter. Most projections, however, remain uncertain as to the overall strength of the event. (El Niño Watch - July SW Climate Outlook)

Precipitation Forecasts: Forecasts point to above-average precipitation for Arizona and New Mexico over the next three months. Given widespread drought conditions, even an average monsoon could help improve drought conditions. 

Temperature Forecasts: Monsoon storm cycles introduce variability into short-term temperature patterns, but the longer-term forecasts call for equal chances for above-, below-, and near-average temperatures. These forecasts are based in part on increasing temperature trends.

1075' - Shortage on the Colorado River, A CLIMAS Podcast Series

Monday, July 14, 2014

Lake Mead from the Hoover Dam - Source: Wikipedia Commons

1075’ – Shortage on the Colorado River is a CLIMAS podcast series that explores what the first ever shortage declaration on the Colorado River would mean to those living in the Southwest. 

1075 refers to the elevation of Lake Mead – in feet above sea level – that serves as the trigger for shared shortage restrictions[1]. While this has never happened before[2], after years of drought and ever-increasing demands on the river, the latest projections from the Bureau of Reclamation suggest the lake could drop below 1075[3] as soon as early 2015.

In this series, we attempt to demystify the rules and regulations that govern water use on the Colorado River and discuss what it means to the people and sectors across Arizona when a shortage occurs. This series will explore the opportunities and consequences of a shortage to construct a nuanced view of a complex issue.

  • Episode 1: Management of the Colorado River (Doug Kenney) - In this episode, we take a broad view of the Colorado River Basin, exploring how the river is managed, who uses the water, and what a potential shortage could mean for the system. Our guest is Doug Kenney, Director of the Western Water Policy Program, a division of the Getches-Wilkinson Center for Natural Resources, Energy and the Environment, at the University of Colorado School of Law.

Douglas S. Kenney’s Bio:
Doug Kenney is Director of the Western Water Policy Program, a division of the Getches-Wilkinson Center for Natural Resources, Energy and the Environment at the University of Colorado School of Law. He researches and writes extensively on several water-related issues, including law and policy reform, river basin and watershed-level planning, the design of institutional arrangements, water resource economics, and alternative strategies for solving complex resource issues. Dr. Kenney has served as a consultant to a variety of local, state, multi-state, and federal agencies, including several Interior Department agencies, EPA, the US Forest Service, and special commissions (e.g., the Western Water Policy Review Advisory Commission); and national governments and non-governmental organizations in Asia and Africa. Additionally, he has made presentations in (at least) 19 states (and the District of Columbia), 7 nations, and 4 continents.


[1] Note: Mead elevation falling below 1075' in a given month does not automatically trigger shortage restrictions. The January 1st forecast from the August 24-month study is the Mead elevation value that determines if a Tier 1 Lower Basin shortage will occur. The 24-month study is a monthly report produced by the Bureau of Reclamation to keep track of Colorado River system reservoirs. So even if Lake Mead is forecasted to drop below 1075' in mid-2015, shortage is not declared unless the 2014 August 24-month study forecasts a January 1st Mead elevation at or below 1075'.

[2] Any shortage before 2026 would be the first declared shortage under the 2007 Interim Guidelines. However, there was a shortage declared in 1963/1964 when Lake Powell was filling up. Drought caused low inflows into Lake Mead and deliveries to the Lower Basin were subsequently cut.

[3] The Applied Climate Science Group in the School of Natural Resources at the University of Nebraska-Lincoln has compiled an impressive array of photos and data relating to the drop in Lake Mead levels - be sure to check it out!

Many thanks to Dr. Mohammed Mahmoud (of the Colorado River Programs / Central Arizona Project) for providing the clarifications in footnotes [1] and [2].

CLIMAS Colloquium: Local Climate Impacts & Global Supply Chains

Friday, March 28, 2014

A video recording is now available on the CLIMAS media page

CLIMAS Colloquium Series

Speaker: Diana Liverman, Co-Director, Institute of the Environment and Regents Professor, School of Geography and Development

Title: “Understanding local climate impacts in the context of global supply chains”
When: 10:30 a.m. - 12:00 p.m. on Friday, 3/28/14
Where: UA Marshall Building, Room 531

 

Abstract: This spring IPCC and the USGCRP will release important reports that document the potential impacts of climate change for the world and for the United States.  Their reports represent the latest science and are designed to be relevant to stakeholders.  In this talk, Diana Liverman will discuss the extent to which these and other assessments cover key sectors of global and regional economies and the challenges involved in understanding local climate impacts in a global economy.   Assessments do not provide adequate analysis of major sectors such as manufacturing and services that underpin our economies and comprise key stakeholders.  In many cases, the local effects of climate extremes and changes can only be understood in a global context - for example our food security in southern Arizona is only weakly connected to agricultural production in our region but is very dependent on climate impacts in other regions (that we import from) and on food prices that are often determined within global trading systems. Liverman will review some recent case studies and proposals to study climate and supply chains as a way to better understand climate impacts in the business sector and across the globe.

Recent Variations in Low-Temperature and Moisture Constraints on Vegetation in the Southwestern U.S.

Friday, April 19, 2013

Dr. Jeremy Weiss, a senior researcher with UA’s Environmental Studies Laboratory, will discuss the importance of seasonality and elevational gradients for understanding the effects of drought and warming on vegetation in topographically complex regions like the Southwest, and explain how projected changes in future regional climate may potentially further or alter these effects.

Starting in the late 1970s, warming in the Southwest has produced fewer cool season freezes, losses in regional snowpack, earlier spring flowering and leafout, and hotter summers, all of which should affect vegetation differently across the region’s diverse climatic and biotic zones. Another potential impact of the ongoing regional warming is changes in how recent and future droughts affect vegetation. One way to examine the effects of drought and a warming climate on vegetation is to compare climatic controls on photosynthesis and transpiration during the major regional droughts of the 1950s and 2000s, periods of unusually dry conditions before and during the recent decades of warming.

Weiss and his colleagues examined indices that represent climatic constraints on foliar growth for both drought periods and evaluated these indices for areas that experienced tree mortality during the 2000s drought. They found that relative to the 1950s drought, warmer conditions during the 2000s drought reduced cold temperature constraints at lower elevations in winter and higher elevations in summer. Warmer conditions also increased aridity (as measured by vapor pressure deficit) from early spring through late autumn. Increased vapor pressure deficits are extremely limiting to foliar growth.

For more information about this research project, visit:
http://www.geo.arizona.edu/dgesl/research/other/climateGEM/climateGEM.htm

Field of Dreams, or Dream Team? Assessing Two Models for Drought Impact Reporting in the Semiarid Southwest

Friday, March 22, 2013

To make decisions about drought declarations, status, and relief funds, decision makers need high quality local-level drought impact data. In response to this need in Arizona, the Arizona DroughtWatch program was created, which includes an online drought impacts reporting system. Despite extensive and intensive collaboration and consultation with the intended public participants, Arizona DroughtWatch has had few consistent users and has failed to live up to its goal of providing decision makers or the public with high quality drought impacts data.

In this talk Dr. Meadow will present results of a project to evaluate the Arizona DroughtWatch program (forthcoming in the Bulletin of the American Meteorological Society), which revealed several weaknesses in the public-participation reporting-system model including: reduced participation due to participants’ over commitment and time constraints, consultation fatigue, and confusion about the value of qualitative impact reports. Based on these findings, the study authors recommend that professional resource agency personnel provide the backbone of drought impacts monitoring to ensure that decision makers receive the high-quality, consistent information they require. Public participation in impacts monitoring efforts can also be improved using this model. Professional observers can help attract volunteers who consider access to high-quality data an incentive to visit the Arizona DroughtWatch site and who may be more likely to participate in impacts monitoring if they see examples of how the information is being used by decision-makers.

Drought Impacts on Dust and Health in New Mexico

Friday, March 1, 2013

Campus Christian Center, Second Floor
University of Arizona

Dust storms create both health issues and transportation hazards. Valley Fever is endemic to the border region and gets carried with the dust. Interstates and local highways are often closed for hours in an attempt to avoid accidents and injuries. Windblown dust concentrations can be very high when strong winds occur during extended droughts - creating “exceptional episodes” of poor air quality. Air quality in rural areas of New Mexico and along the US/Mexico border is normally acceptable and well below the US EPA’s air quality standards for particulate matter. But these episodes expose millions of people to particulate levels that exceed air quality standards.

The state climatologist of New Mexico is working with the New Mexico Departments of Health and the Environment to reduce exposure during dust storms. They are investigating the dust emission generation, transport, and human exposure processes and trying to develop mitigation strategies. Determining the sources of windblown dust through ground observations and remote sensing are improving monitoring and forecasting efforts.

Southwest Climate Podcast: Arizona "Blizzard" - Drought Remedy?

Friday, February 1, 2013

Was the "blizzard" in February unprecedented for Arizona, and did climate change play any role? In this month's podcast, Gregg Garfin and Zack Guido discuss this and the influence the storm and recent temperatures had on the state's snowpack. They also explore the status of drought in both Arizona and New Mexico, and what the precipitation forecast looks like for the next few months.