Wednesday, November 28, 2012

Climate change raises Dust Bowl-like specters

Could climate change bring another version of the Dust Bowl? Some look at the current drought in the high plains and suggest that possibility. (U.S. Department of Agriculture Drought Monitor map: Red is extreme drought, maroon is exceptional)

Colorado, Nebraska, Kansas, Oklahoma and Wyoming experienced a large dust storm in October, following "preparation of fields for fall planting, and could be the first act of an encore performance" of the the 1930s Dust Bowl in the Great Plains, where the current drought is most intense. Temperatures are expected to remain higher than normal across most of the western half of the country in the next few months, Melissa Gaskill of Scientific American reports.

"If the drought holds on for two or three more years, as droughts have in the past, we will have Dust Bowl conditions in the farming belt," Environmental Working Group agriculture expert Craig Cox told Gaskill. "It could be in a sense an invisible Dust Bowl, not like the big storms before, but withered crops, dry stream and other disasters that accompanied the Dust Bowl." Soil-conservation programs and different farming practices make a repeat of the Dust Bowl unlikely in the foreseeable future, experts think.

Agriculture on the semi-arid southern Great Plains has relied on irrigation from the Ogallala Aquifer since the 1940s, which has been depleted by half. Some fear that most of the remaining reservoir will be gone in about 30 years. Climate change "has brought less rain as well as hotter temperatures that increase evaporation, forcing farmers to use even more water," Gaskill writes. Texas Tech University Climate Science Center director Katherine Hayhoe told Gaskill that the agriculture systems in semiarid states -- Colorado, Kansas, Oklahoma and Texas -- are vulnerable. "We built these vulnerabilities into the system and climate change is the final straw that may break the camel's back," Hayhoe said. (Read more)

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