Drought: A Creeping Disaster

Climatologists call drought a “creeping disaster” because its effects are not felt at once. Others compare drought to a python, which slowly and inexorably squeezes its prey to death. The great aridification of 2011 began last fall; now temperatures in many states have spiked to more than 100 degrees for days at a stretch. A high pressure system has stalled over the middle of the country, blocking cool air from the north. Texas and New Mexico are drier than in any year on record. The deadly heat led to 138 deaths last year, more than hurricanes, tornadoes or floods, and it turns brush to tinder that is vulnerable to lightning strikes and human carelessness. Already this year, some 40,000 wildfires have torched over 5.8 million acres nationwide — and the deep heat of August is likely to make conditions worse before they get better. Climatologists disagree about what caused this remarkable dry-out. But there is little disagreement about the severity of the drought — or its long-term implications. When I asked Richard Seagar, who analyzed historical records and climate model projections for the Southwest for the Lamont-Doherty Earth Observatory at Columbia University, if a perpetual drought was possible there, he replied: “You can’t really call it a drought because that implies a temporary change. The models show a progressive aridification. You don’t say, ‘The Sahara is in drought.’ It’s a desert. If the models are right, then the Southwest will face a permanent drying out.”...more