Parts of the West are beginning to experience "Dust Bowl-like conditions," according to scientists at the University of Colorado-Boulder, who have noticed an uptick in the amount of dust being blown across the Great Plains and "large swaths of the West."
Tracking dust is difficult, mainly because there are very few teams monitoring dust storm incidents. But Jason Neff, co-author of the study, published in Aeolian Research Monday, says his team found a new way to gauge it.
"The thing we found is calcium in rainfall," Neff says. "The reason this works is because a lot of desert soils contain calcium. When they blow up into the air, it dissolves into the rain and falls to the ground."
By monitoring this calcium, which the team took from the National Atmospheric Deposition Program established in the 1970s to study acid rain, Neff says researchers can be reasonably sure that the amount of dust being blown around has greatly increased since 1994.
"In some cases, it's gone up a few hundred percent," he says. "There are three bulls-eyes on the map – the biggest is a western slope of the Rocky Mountains, another is in the Great Plains, and a third is in the drier areas of Oregon and Washington."
The change could be attributable to recent years of drought and changes in land use. Neff says in many areas, grazing, off-road vehicle riding and urban development may have stripped the land of some of the vegetation that helps hold top-level soil in place.
In those areas, there has been anecdotal evidence of dust storms, which can cause visibility problems for drivers, but more importantly, dust particles can also cause respiratory problems or, as much of the Midwest learned in the 1930s, extreme problems growing crops. Coupled with years of drought, some areas might become unsuitable for crops, he says.
"The Dust Bowl period in the mid 1930s was a phenomenon that combined a few years of drought with people trying to grow crops in marginal land," he says. "We've gotten better at how and where we practice agriculture, so we're not likely to experience something as dramatic as the Dust Bowl again."
But in smaller areas, farming might become more difficult, especially in some of the harder-hit areas. Neff says there is little that can be done except to hope for more rain.
"When there's little rain, it's hard to do anything," he says. "In those places they might just be stuck waiting for the drought to end."