New climate record shows century-long droughts in eastern North America

Tuesday Aug 19, 2008
by ANDREA GIBSON

Weak sun created cool oceans, lowered rainfall seven times in 7,000 years

ATHENS, Ohio (Aug. 19, 2008) – A stalagmite in a West Virginia cave has yielded the most detailed geological record to date on climate cycles in eastern North America over the past 7,000 years. The new study confirms that during periods when Earth received less solar radiation, the Atlantic Ocean cooled, icebergs increased and precipitation fell, creating a series of century-long droughts.

A research team led by Ohio University geologist Gregory Springer examined the trace metal strontium and carbon and oxygen isotopes in the stalagmite, which preserved climate conditions averaged over periods as brief as a few years. The scientists found evidence of at least seven major drought periods during the Holocene era, according to an article published online in the journal Geophysical Research Letters.