Arid Lands & Resources

The Southwest has grown hotter and drier during the past decade, and new climate data from the federal government shows these changes have been dramatic, shifting the long-term averages that represent the region’s “normal.”

The US Bureau of Reclamation last week warned water users to brace for a 500,000 acre-foot cut in water from the Colorado River as a historic drought continues to tighten its grip on the Southwest.

The US Bureau of Reclamation last week warned water users to brace for a 500,000 acre-foot cut in water from the Colorado River as a historic drought continues to tighten its grip on the Southwest.

Interstate water disputes are as American as apple pie. States often think a neighboring state is using more than its fair share from a river, lake or aquifer that crosses borders.

Climate experts say drought conditions in Arizona are the type usually only seen once or twice in a century and one season of rain won’t fix it.

Lack of monsoon rainfall last summer and spotty snowfall this winter combined to worsen the Western drought dramatically in the past year, and spring snowmelt won’t bring much relief.

The Colorado River is one of the most highly developed surface water systems in the world, but demand for the river’s water continues to exceed supply. University of Arizona geosciences professor Connie Woodhouse discusses the impact of a warming climate on the Colorado River. She is the featured speaker for the annual College of Science lecture series April 15.

Connie Woodhouse spoke with Leslie Tolbert, Regent’s professor emerita in Neuroscience at the University of Arizona.

Droughts are lasting longer and rainfall is becoming more erratic across the Western hemisphere, according to a new study published by the US Department of Agriculture. 

Annual precipitation in our region dropped by eight times more than in the West as a whole from 1976 to 2019. The total decline of 3.2 inches in the Southwest compared to 0.4 inches regionwide.