Title: Climate Change in the Southwest - Potential Impacts (U.S. National Park Service)
Headings: Climate Change in the Southwest - Potential Impacts
Series: Climate Change in the Southwest
Climate Change in the Southwest - Potential Impacts
Climate change in the Southwest
Potential climate change impacts
Water
Vegetation
Vegetation shifts
Fire
Impacts by Region

Content: The models used by the US Global Change Research Program indicate that the average annual temperature in the Southwest may increase by 4 to 10 degrees Fahrenheit, compared to temperatures between 1960 and 1979. Atmospheric circulation patterns are likely to change, causing southwestern climate to become more arid overall (Christensen et al. 2007, Seager et al. 2007). The aridity may become much worse during La Niña events, causing droughts that may be more severe than any other droughts seen in the climate record, including the medieval megadroughts (Seager et al. 2007, Dominguez et al. 2009). The Southwest may also experience more frequent and longer-lasting heat waves, and the precipitation that does fall is more likely to come from extreme precipitation events (Diffenbaugh et al. 2005). Human- caused changes in winter climate appear to be happening already: