Future Western droughts could last an average of 12 years, spanning half of the region and severely reducing Colorado River flows that supply millions of people . . . . "Climate change is moving us in the direction of a perpetual state that is of the Dust Bowl type."
The models forecast a temperature increase of 5.4 degrees Fahrenheit by 2060 in the interior West, largely because of the buildup of heat-trapping gases emitted by fossil-fuel combustion. . . . Some droughts could be 25 percent worse than the 1930s Dust Bowl . . . On average, half of the interior West will suffer from severe drought each year . . . . Last year . . . a team led by U.S. Geological Survey hydrologist Christoper Milly . . . found that by 2050, drier conditions could lead to a 10 to 20 percent drop in runoff from rivers in the U.S. West.
This isn't the distant future we're talking about here. My kids will be middle aged, and I may well be alive even, in the time frame these predictions are discussing.
The article isn't published yet, although it probably will be. Other studies have argued for a less severe impact. But, this is one scientifically credible voice that is suggesting that the West is in deep shit when it comes to future water supplies.
This isn't an end of civilization as we know it scenario. A majority of Colorado water goes to marginal agriculture. The entire agriculture sector is already economically smaller than fishing and hunting and camping and rafting in Colorado, and it will suffer further. About half of urban water use is devoted to lawns and golf courses. It is possible to be more efficient in indoor water use than we are today. Kill horticulture and our lawns, and life will go on with even 60%-70% smaller water supplies.
But, this study is a shot across the bow to say we are heading for major changes.
Hat Tip to Dexter's Lab.
UPDATE: The University of Colorado is advising us, in a study published in today's edition of the journal Nature, that we don't need to wait for global warming effects either. Greenland's icesheet is losing water in the past two years at 250% of the rate in the previous two years:
The Greenland ice sheet - which holds 70 percent of the world's fresh water - is shedding ice at an accelerating pace . . . . "This raises the question of a much larger loss of the ice sheet in this century that we previously thought," [CU Research] Velicogna said. . . . The Greenland sheet lost the equivalent of 164 million cubic miles of ice from April 2004 to April 2006 - enough water to more than fill Lake Erie. . . . The loss of ice appears to be linked to climate change and a 4.4 degree Fahrenheit increase in recorded Greenland temperatures in the last 20 years. . . . "One the discharge starts it doesn't stop quickly, even if the temperature falls," Velicogna said. "It's like a car rolling down, down."
The data are collected via satellite.