This summer, record high temperatures have scorched much of the United States. Add little rainfall to the intense heat and the result has been corn crop failure and worries about much worse.
In fact, moderate to severe drought now covers nearly 64 percent of the lower 48 states, according to statistics released today by the U.S. Drought Monitor at the University of Nebraska, Lincoln, making it one of the most widespread droughts in the past century.
The nation hasn't seen a drought this big in more than 50 years, according to a report released earlier this week by the National Climatic Data Center, part of the National Oceanic and Atmospheric Administration.
As the extended dry period threatens corn and other crops, fears are growing that we are headed for another Dust Bowl, a series of severe droughts in the 1930s that filled the prairie states with plumes of dusty soil.
But the Dust Bowl was about more than just dry weather.
The country was also in the midst of recession, adding social upheaval to the uncertain climate, said John Nielsen-Gammon, an atmospheric scientist at Texas A&M University in College Station. Unlike today, small family farms dominated rural areas at the time. And agricultural practices were less sophisticated than they are now -- all factors that contributed to the period’s extreme environmental and economic consequences.
The Dust Bowl also involved year after year of severe drought, unlike the current situation, which has only just begun in most places.
“For most of the central and northern United States, this is a drought that has only developed over the past 90 days, so at this point it’s just a single year of brief but intense drought,” Nielsen-Gammon said. “Most farmers can deal with one year of drought.”
“If this were to continue like this next year and the year after that,” he added, “then we’d be talking about major long-term impacts like the Dust Bowl.”
On a geological scale, the Northern Plains states have experienced a handful of long-term dry periods since the last Ice Age, Nielsen-Gammon said. For several hundred years at a time over the past few millennia, the Great Plains have been nothing but sand dunes.
More recently, over the last 100 years, droughts have repeatedly occurred from Texas to Minnesota for reasons that are hard to predict and hard to explain. Unlike winter weather patterns, which are often controlled by El Niño’s and other variations in Pacific Ocean’s surface temperatures, summer rainfall levels can be random. Often, Nielsen-Gammon said, whether a summer is wet or dry comes down to luck.
This year, after a winter with little snow, a large ridge of high pressure has stalled over the central United States, deflecting most storms into Canada and New England, said David Miskus, a meteorologist at NOAA’s Climate Prediction Center in Silver Spring, Md.
In the Midwest, Miskus said, the current drought is comparable to one that struck in 1988. More severe were the Dust Bowl droughts in the 1930s along with a series of droughts that lasted for years in the 1950s. In general, he added, it’s difficult to compare the severity of current droughts with ones that occurred before 2000, when meteorologists adopted a new method for tracking data.
And every drought is different: Some are localized and intense. Some are widespread and long lasting.
Already, the drought of 2012 is causing problems for both farmers and consumers. Dry topsoil and excessive heat have had the biggest impact so far on corn crops, leading to lower yields and rising prices, which will likely translate to more expensive meat and dairy products, too. The U.S. Agriculture Department announced on Monday that 38 percent of the nation’s corn crop is currently in poor or very poor condition. Soybeans may be next.
But, Nielsen-Gammon said, the nation learned some important lessons from that period that make an identical scenario unlikely to happen again.
To reduce soil erosion, for example, farmers have adopted new tilling, plowing and planting techniques that aim to avoid large patches of barren, heavily disturbed soil. Starting with Roosevelt-era projects, irrigation infrastructure is also much better now. Society has also changed.
“Back in the Dust Bowl, most people lived in rural areas on farms and that’s no longer the case, so it’s not going to have the same kind of impact as it did back then,” Nielsen-Gammon said. “We can worry now, but it’s clear the Dust Bowl was worse.”
It’s hard to know what’s to come, Miskus said. Some models are predicting an El Niño event later this year, which would likely bring above-average precipitation to the south in the winter and spring. But now is the critical period for Plains-state farmers, who are sweating it out through corn-pollination season.
Over the next three months, the Climate Prediction Center’s models are projecting continued hot and dry conditions and intensifying drought throughout much of the central and eastern regions of the country, according to data released this morning. The Southwest is one region where wet weather is likely to return.
A few good soakings could go a long way toward alleviating concerns. But time is of the essence.
“The good news is that this drought formed recently,” Miskus said. “Since it’s still short-term, if we get into a wet spell, it could be improved pretty quickly.”
“If it’s going to rain,” he added, “it’s got to start here pretty quick.”