Southwest Climate Outlook - El Niño Tracker - January 2021
Assistant Research Professor, Arizona Institutes for Resilience
Assistant Professor of Anthropology, School of Anthropology
Ben McMahan joined CLIMAS after completing a PhD in Sociocultural Anthropology at the University of Arizona. His dissertation research was on hurricanes and disaster on the U.S. Gulf Coast, where he focused on
- Human interactions in dynamic social and environmental contexts,
- Risk perception and landscape changes during and after disaster, and
- Social network and policy responses to governance issues related to the acute threats of disaster; as they layer onto long term environmental issues and landscape scale changes.
He was also a key contributor to UA Bureau of Applied Research in Anthropology (BARA) collaborative/trans-disciplinary research on the social, economic, and environmental impacts of the US Oil and Gas industry (2007-2011), and the aftermath of the Deepwater Horizon oil spill (2010-2013).
At CLIMAS, his research activities included tracing how climate information is incorporated into regional decision maker networks, leading CLIMAS team research on the risks and effects of climate extremes, and collaborative research on the effects of climate variability on phenology and temporality of native plants in the region. He was also responsible for working to develop collaborative research opportunities and outreach efforts at CLIMAS, and as part of ongoing assessment and science/strategic planning, he contributed to strategic planning used to prioritize future research and outreach directions. He also coordinated publication of the monthly Southwest Climate Outlook, produced the Southwest Climate Podcasts, and was the online editor for CLIMAS’ blog - Southwestern Oscillations.
Sea surface temperature (SST) forecasts for February 2021 call for below-normal conditions across the equatorial Pacific (Fig. 1), extending the trend of the last 4-5 months (Fig. 2). International climate outlooks generally see La Niña conditions persisting through winter 2020-2021 before returning to ENSO-neutral conditions over spring 2021.
Forecast Roundup: On Jan 12, the Japanese Meteorological Agency (JMA) maintained its observation of an ongoing La Niña event, and with a 50-percent chance of this event either continuing or a return to ENSO-neutral conditions. On Jan 14, the NOAA Climate Prediction Center (CPC) ENSO status was at La Niña Advisory. The CPC called for a 95-percent chance of La Niña continuing through March and a 55-percent chance of transition to neutral during late spring or early summer. On Jan 14, the International Research Institute (IRI) issued an ENSO Quick Look (Fig. 3), noting “the east-central Pacific is roughly 1.2 degrees C below average, and all key atmospheric variables are consistent with La Niña conditions”. On Jan 19, the Australian Bureau of Meteorology was at official La Niña status and noted, “La Niña is likely to have reached its peak with respect to sea surface temperature patterns in the eastern and central Pacific Ocean”, but that impacts are expected to persist into spring. The North American Multi-Model Ensemble (solid and dashed black line, Fig. 4) indicates moderate La Niña conditions are expected for the next few months, with a return towards ENSO-neutral conditions by late spring or early summer.
Summary: La Niña conditions are present and likely to remain in place through winter or early spring. The monthly and seasonal climate outlooks suggest drier than normal conditions over the same period, consistent with La Niña events in the U.S. Southwest. Drier than normal does not mean zero precipitation, however (for example, there is a large event forecast for the region at the time of this writing). Still, the likely outcome would be less frequent events and lower seasonal totals, consistent with long-term averages for La Niña winters.
- Figures 1 - Australian Bureau of Meteorology - bom.gov.au/climate/enso
- Figure 2 - NOAA - Climate Prediction Center - cpc.ncep.noaa.gov
- Figure 3 - International Research Institute for Climate and Society - iri.columbia.edu
- Figure 4 - NOAA - Climate Prediction Center - cpc.ncep.noaa.gov