Canadian scientist warns of potential ‘megadrought

Emma Graney in the Leader Post (Saskatchewan): When a drought hit North America in the 1930s, creating a giant dust bowl and crippling agriculture from Saskatchewan to Oklahoma, it entered history as the Dirty Thirties. But University of Regina paleoclimatologist Jeannine-Marie St. Jacques says that decade-long drought is nowhere near as bad as it can get.

St. Jacques and her colleagues have been studying tree ring data and, at the American Association for the Advancement of Science conference in Vancouver over the weekend, she explained the reality of droughts. “What we’re seeing in the climate records is these megadroughts, and they don’t last a decade — they last 20 years, 30 years, maybe 60 years, and they’ll be semi-continental in expanse,” she told the Leader-Post by phone from Vancouver.

The big concern, she says, is that there’s no reason a megadrought won’t hit the continent again. “When Europeans settled North America ... we know from tree ring records that it was a very wet period, and so people’s sense of what’s normal is probably not correct,” St. Jacques said. “We’re certainly very scared in the community, because there’s no reason why these things shouldn’t come back.”...

Wind erosion carries topsoil from farmland during the Dust Bowl, circa 1930's, from the USDA