Tracking calcium deposits shows big increase in dust deposition in the past couple of decades
By Bob Berwyn
FRISCO — Significant dust storms the past few years have had a big impact on the timing of snowmelt in the Colorado Rockies, but scientists haven’t been able to say for certain if those events are becoming more frequent.
Now, a new study from the University of Colorado Boulder shows that the amount of dust deposition has increased, at least during the 17-year span covered by the researchers, who tracked calcium deposits to reach their conclusions. Calcium dissolved in precipitation has long been measured by the National Atmospheric Deposition Program as a way assess acid rain.
The scientists reviewed calcium deposition data from 175 NADP sites across the United States between 1994 and 2010, measuring increases in calcium deposition increased at 116 locations. The sites with the greatest increases were clustered in the Northwest, the Midwest and the Intermountain West, with Colorado, Wyoming and Utah seeing especially large increases. Continue reading “Colorado scientists quantify increased dust pollution”