In the Southwest, the most widespread example of species redistribution is the movement of woody plants like creosote bushes and mesquite trees into native grasslands. The spread of invasive species is also considered a form of species redistribution. These changes occur due to long-term environmental changes like climate change, short-term environmental disturbances like drought or fire, or human-induced land use changes like ranching. Research indicates species ranges are shifting on global and regional levels, towards the poles and upwards in elevation. (Learn more)
More than 35 percent of Arizona’s land and almost 60 percent of New Mexico’s land is used for farming and ranching. Thus climate change-related impacts on the Southwest landscape will most likely have significant impacts on the Southwest’s agricultural sectors. Changes in water availability, vegetation cover, carbon dioxide levels, and frequency of extreme events like flood, drought, or frost will impact crop and forage production, increasing costs for both producers and consumers. (read more)
For five consecutive years, drought in the Upper Colorado River Basin limited the water flow into Lake Powell to no more than 62 percent of the historical average. In 2004, the mammoth reservoir was only one-third full. This precipitous decline in water storage highlighted the vulnerability of the resource to the confluence of climate and societal demand.
In the West, as much as 70 percent of the region’s precipitation falls during winter. Arizona and New Mexico are critically dependant on this winter precipitation. The region’s two main water lifelines, the Colorado River and the Rio Grande, tap the winter snows in the Rocky Mountains for approximately 70 percent of their annual water flow. (Read more)
Current observations suggest that climate change is altering streamflows in ways that negatively impact water supply for southwestern populations. Many climate models suggest that these changes will worsen as the climate warms, accentuating the natural variability inherent in river flows.
Since water is one of the most vital resources in the arid Southwest, the consequences of reduced streamflows and changes in the timing of peak river flows will impact water consumption, agriculture production, economic growth, recreation opportunities, and electricity generation, among other vital services. (Find out more)
Groundwater provides drinking water to urban and rural communities and supports agriculture and industry, all of which have helped enable rapid population growth in Arizona and New Mexico. Population expansion, however, has not been without its consequences. It has led to increasing groundwater withdrawals that are outpacing the rate at which the vital resource is naturally replenished. As a result, the region’s groundwater resources are among the most overused in the United States (continue reading).
Health risks are linked to climate change through direct and indirect cause-and-effect chains, and depend on factors such as a person’s age, health condition, economic status, access to quality healthcare programs, and exposure to the elements. In the Southwest, regional health risks linked to climate change include extreme heat conditions, poor air quality, and increased food-, water-, fungal- and animal-borne diseases (Read More).
In the Southwest, climate is an important natural resource and a draw for tourists. Many people come to the region to take advantage of its warm, mild winters, to boat or kayak in the lakes and rivers, or to enjoy snow sports in the higher elevations.
An invasive species is a plant, animal, or microbe that adversely affects the native ecosystem upon introduction to a new community. Invasive species are well-adapted to encroach upon new territory, and invaders compete with native species for resources like water and soil nutrients. Many invasive species are so well-adapted to diverse conditions that they can outcompete their native counterparts, leading to environmental damage and decreased biodiversity. Regional impacts of climate change, including warmer temperatures, decreased precipitation, and increased levels of carbon dioxide will affect how and where invasive species migrate and colonize (Read more).
Despite the Southwest’s arid climate, rivers in the region are not immune to overflowing their banks and flooding city streets, farms, and desert. Climate change likely will increase both flash floods and regional floods, making the region’s growing population more susceptible to losses of life and property. How climate change alters future floods remains an open-ended question. However, recent observations and research are contributing to a better understanding of flooding in the Southwest (read more).