Researchers from the University of Colorado at Boulder have found that the dust blown over the West has increased in the last 17 years and is predicted to rise more in the coming years.
Dust emission has escalated over the years and this could be because of a variety of factors including windstorm frequency, drought cycles and changing land-use patterns. According to the researchers from the University of Colorado at Boulder, this increase has impacted both the region where the dust is picked up from and the region where the dust is blown to.
Janice Brahney, who led the study as a CU-Boulder doctoral student reveals that these dust storms generally cause a shift in nutrients on the surface of the Earth and since dust in particular areas is not monitored regularly, it is difficult to determine its movement.
The increasing dust coating the snowpacks in the Southern Rockies and the rising dust storms experienced by the residents of the West focused the scientists' attention toward this phenomenon. However, the extent of this increase has not been determined as dust hasn't been monitored regularly.
For the study, researchers had to first determine if calcium deposition could be used for dust measurement as calcium has the characteristics of mixing in the atmosphere before falling to Earth during precipitation. Brahney and her colleagues reviewed calcium deposition data from 175 National Atmospheric Deposition Program (NADP) sites across the United States between 1994 and 2010, and found that calcium deposition had increased in 116 sites. They were also able to determine that this increase had taken place due to dust erosion as none of the other contributing factors like industrial emissions, forest fires or ocean spray had increased during the study period.
Researchers say that this study is important as too much of dust erosion can cause an exhaustion of natural fertility of the soil from where the dust has blown off. Wind has the tendency of blowing away finer particles in the soil that are known to contain most nutrients and hold on to most of the soil moisture. Also, the increase of dust in the air can cause further problems like poor visibility and poor air quality.
