NASA is keeping track of dust that settles on snow in the Rocky Mountains. The research will help hydrologists improve their predictions for how fast the Colorado River will rise this spring.
Michelle Stokes is a hydrologist for the Colorado River Basin Forecast Center in Utah. Her job is to project how much snowmelt will flow into the Colorado River and when it will arrive.
“It’s been known for a long time that if there’s a lot of dust on the snow it’s going to melt faster,” she says. “We always thought it would be really nice if we could quantify that, because it would improve our forecast, especially the timing of when the runoff comes.”
Stokes teamed up with Tom Painter of NASA’s Jet Propulsion Laboratory in California. Painter uses satellites to measure the dustiness of snow on a daily basis. A blanket of dust absorbs more sunlight than a bright white snowbank, so it raises the temperature a few degrees.
That was the missing piece in the hydrologists’ forecast model, Painter says. “So if the snowpack’s dirtier, they have to essentially increase the temperature in their model. It’s a huge impact on their runoff forecasts.”
This is the second year hydrologists have used the improved model. The forecasts help the U.S. Bureau of Reclamation manage the reservoirs on the Colorado River.