Human-influenced climate warming has already reduced rainfall and increased evaporation in the Mideast, worsening water shortages. Up to now, climate scientists had projected that rainfall could decline another 20 percent by 2100. But the Dead Sea cores suggest that things could become much worse, much faster.
Thousands of years before Biblical times, during a period when temperatures were unusually high, the lands around the Dead Sea now occupied by Israel, Jordan and surrounding nations suffered megadroughts far worse than any recorded by humans. Warming climate now threatens to return such conditions to this already hard-pressed region.
As the American Southwest grows hotter, the risk of severe, long-lasting megadroughts rises, passing 90 percent this century if greenhouse gas emissions continue at their current pace, a new study from scientists at Lamont-Doherty Earth Observatory says. Aggressively reducing emissions can cut that risk.