Stalagmites in Northeast Brazilian Caves Confirm 9,000-Year Model of Diminishing Rainfall Developed by UMass Amherst Geoscientists February 24, 2009 by Insciences Organisation
AMHERST, Mass. – Until recently, researchers studying climate history in Brazil’s dry Nordeste region expected it to have wet and dry periods similar to the rest of South America. But over the past 9,000 years, the region has shown just the opposite, drought when rain was expected, and vice versa. Geoscientists from the University of Massachusetts Amherst and the University of Sao Paolo, Brazil, with others, report this week that they’ve identified the cause as a surprising air circulation pattern.
“Our speleothem records are really the first long, high-resolution records of rainfall for this region. As we pieced the record together, what we found surprised us. We had not expected this area to show a pattern of changes in rainfall that was different—in fact opposite—from the rest of the Southern Hemisphere tropics in South America.”