There’s more to drought than a shortfall of rain or snow, says climatologist Brad Fuchs of the National Drought Mitigation Center. “We’re also looking at the full water cycle,” he says. “Water that’s coming in, water that’s leaving, water that’s being stored in lakes, reservoirs, streams, the soil or groundwater.”
If a region is in “extreme drought,” it’s only been that dry 5 or 10 percent of the time in its history. Almost 20 percent of the country is in that state at present. More than 2 percent is in “exceptional” drought. “You’re only going to expect to see conditions like that every 50 to 100 years,” Fuchs says.
The total amount of drought hasn’t been trending upward, Fuchs says, but it is impacting different parts of the country. Atmospheric scientists who studied droughts since 2000 found that warmer atmospheric temperatures, which pull moisture from plants, soil and bodies of water, can play a bigger role than rainfall shortages in creating drought conditions.
Population growth in drought-prone areas is another factor in drought stress. More “straws in the cup” add to the challenges for water resource managers, Fuchs says.
Conservation strategies that have become commonplace in the West — from banning lawns and low flow toilets to recharging aquifers with purified wastewater — need to be a bigger part of the conversation in states where drought conditions have become more serious than in the past, Fuchs says.
“We don’t know when the next drought is going to begin, and we don’t know how long it will last when it does start,” he says. “If it’s going to continue to be dry in a region, don’t waste the water on your yard.”
