Water Weirding: American Southwest on Uncertain Ground

Global climate models have differed on what a warming globe will look like, but most agree that the American Southwest is in for a dry spell. The Southwest is familiar with drought and fire. But if a team of international climate scientists are correct, we can no longer expect historical water records in the region to be a guide for future management strategies.

In addition, the study is one of the first to link manmade global warming to direct changes in the hydrological parameters of a region. The scientists found that up to 60% of the trends in river flow, minimum winter air temperature, and spring snowpack over the past 50 years are a direct result of human impact.

Given climate change, river runoff in the region is expected to fall by 10%–30% by 2050. In an area where there are already political battles, water shortages, and strict management, even a 10% decrease in runoff is a major problem. Lake Mead, the reservoir for cities and farms throughout the entire Southwest is already only half full, but by 2021 without changes in water management the scientists give the lake a 50-50 chance of drying up completely.

Current policy on water management does not take global warming's impacts into account. Water weirding, like the drought conditions found in Atlanta will continue to surprise us until cities and regions begin to account for global climate change. To learn more about how the scientists figured out the impacts, follow the link to the American Institute of Physics. To green your own water use, check out Treehuggers How To Green Your Water.

via:: Physics Today