Tomorrow's Superstorms May Speed Erosion

Rainstorms 50 to 100 years from now may be more intense and more frequent than today's, and may pack more soil-eroding power.

Stormwaters running off landscapes—orchards, vineyards, even hilly backyards or parklands—could increase by a worrisome 20 to 30 percent in some parts of America, Agricultural Research Service (ARS) scientists in Arizona and their colleagues have estimated. In turn, the runoff might wash away 25 to 50 percent more soil, the researchers' experiments suggest.

Mark A. Nearing, a soil scientist who heads the ARS Southwest Watershed Research Center in Tucson, Ariz., collaborated with other experts from the United States and abroad to develop these projections. The scientists ran climate data from the past century through seven leading mathematical models to get a glimpse of what might be ahead for erosion-prone farms and ranches of the American Southwest and other sites here and overseas.

Scientists based the estimates on an array of factors, including the presumption that the U.S. climate trends of the past 100 years—and farming practices—will continue along the same lines, according to Nearing. Researchers can use these findings and others to get a better idea of the possible soil-erosion consequences of global climate change. That foundation could lead to better ways to protect vulnerable topsoil from the erosive force of tomorrow's thunderstorms.

Read more about the study in the September 2006 issue of Agricultural Research magazine.

ARS is the U.S. Department of Agriculture's chief scientific research agency.