Dead Sea climate episodes said 'dramatic'

Climate changes in the Dead Sea area in past centuries have caused surprisingly fast episodes of desertification, sometimes within just decades, scientists say. Researchers from the University of Bonn and Israeli colleagues analyzing pollen in sediments and fluctuations in sea levels have called their findings "dramatic." The researchers took a 68-foot-long sediment sample on the west bank of the Dead Sea and analyzed fossil pollen for evidence of different levels of precipitation and temperature. "This allowed us to reconstruct the climate of the entire post-glacial era," Bonn researcher Thomas Litt said. "This is the oldest pollen analysis that has been done on the Dead Sea to date." Three different formations of vegetation existed in turn around the Dead Sea, researchers said. In moist phases, lush vegetation similar to what exists around the Mediterranean Sea today thrived. When the climate turned drier, steppe vegetation took over, and desert plants characterized even drier episodes. Some of the changes between moist and dry phases were extremely rapid, researchers said. "Our results are dramatic; they indicate how vulnerable the Dead Sea ecosystems are," Litt said. "They clearly show how surprisingly fast lush Mediterranean sclerophyll vegetation can morph into steppe or even desert vegetation within a few decades if it becomes drier."