Human-caused climate change is "well underway" in the southwestern United States, with rapidly rising temperatures and dwindling water supplies, according to a sweeping new federal report unveiled today.

Any lingering doubt about the science is largely gone, according to Joe Galewsky, a University of New Mexico climate scientist who was not one of the report's authors, but who has reviewed its conclusions.

A series of studies in the last year have linked declining mountain snowpack to our north and warming caused by greenhouse gases emitted by human burning of fossil fuels, noted Galewsky, who recently returned from meetings in Washington, D.C., to talk to government leaders about the issue.

"Across the board, on the left and the right, people recognize that this is happening and we need to do something," Galewsky said.

In particular, flow in the Colorado River basin - where Albuquerque now gets its drinking water - is declining, and is projected to decline even more, according to the report. Temperatures across the Southwest have already risen 1.5 degrees F on average since the 1970s, and are projected to rise 4 to 10 degrees more over the next century.

"In the Southwest we're already getting literally cooked," said Overpeck, a professor at the University of Arizona.

Overpeck, who also was one of the lead authors on the 2007 climate science report of the Intergovernmental Panel on Climate Change, said the report's message is that it is becoming ever more clear that we must reduce our greenhouse gas emissions. "We need to reduce them," he said, "a lot, and fast."

Read the report.