Century of Drought May Be Ahead
A drought that gripped western North America from 2000 to 2004 was the worst since the Middle Ages, but such extreme conditions may become normal during the next 100 years, finds a new study.
During the drought that started at the turn of the century, forests withered, river basins were depleted, crop productivity dropped and carbon sequestration — the natural capturing of carbon in the atmosphere — was cut in half across the western United States, Canada and Mexico. The last two periods to match those severe conditions were in the Middle Ages, from 977 to 981 and 1146 to 1151, according to researchers using tree ring data. But by the end of this century, 2000 to 2004 may be remembered as a relatively wet period if conditions worsen as the new study suggests. The researchers forecast that a 21st century “megadrought” may be ahead and that 80 of the 95 years from 2006 to 2100 may have precipitation levels as low as, or lower than, the drought from 2000 to 2004.