Utah’s largest water reservoir is contained in snowpack that releases water all summer long. Scientists estimate that in the Colorado River basins, annual mean discharge from snowpack decreases by 9.3% for every degree Celsius of warming.
This is not just because of less runoff. U.S. Geological Survey scientists found that loss of reflective snowpack also increases evaporation.
One way to increase snowpack might be through weather modification. The Utah DWR has had an operational cloud seeding program since 1976, spraying silver iodide particles into clouds to encourage formation of ice crystals. DWR claims that cloud seeding increases precipitation by 5% to 15%; the science is still not conclusive as to how well it works outside of a laboratory.
Colorado River flow dwindles as warming-driven loss of reflective snow energizes evaporation (Science, 13 Mar 2020): science.sciencemag.org/content/early/2020/ 02/19/science.aay9187
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This is an excerpt from our April EnviroNews column. View the full article here.