Water supplies tracked
In a study of 421 drainage basins in the northern hemisphere, including the upper Great Basin, a group of scientists have tried to calculate the impact of climate change on water supplies, without much luck. The Great Basin contains most of Nevada.
“Using a multi-model ensemble of climate change projections, we find that these basins—which together have a present population of approximately 2 million people—are exposed to a 67 percent risk of decreased snow supply this coming century,” wrote the authors in an abstract of the study published Nov. 12 in Environmental Research Letters. “Further, in the multi-model mean, 68 basins (with a present population of more than 300 million people) transition from having sufficient rainfall runoff to meet all present human water demand to having insufficient rainfall runoff.”
But the study was unable to predict whether the climate change would cause gains or loss in water supplies because “internal climate variability creates irreducible uncertainty in the projected future trends in snow resource potential, with about 90 percent of snow-sensitive basins showing potential for either increases or decreases over the near-term decades.”
Authors of the study, “The potential for snow to supply human water demand in the present and future,” are Justin S. Mankin, Daniel Viviroli, Deepti Singh, Arjen Y Hoekstra and Noah S. Diffenbaugh.
International climate talks begin this month in Paris on plans to curb carbon emissions.