Science

The U.S. Drought Monitor shows the extent of current drought conditions.
Click on the map to go to a site with a full report and statistics.

 Current U.S. Drought Is Most Severe in Decades

Much of the United States is suffering through a drought of historic proportions, illustrating the risk of extreme weather posed by climate change. The National Oceanic and Atmospheric Administration’s weekly drought monitor reported that as of January 1, more than 60 percent of the continental U.S. was in a moderate or worse drought, and more than 40 percent was in a severe or worse drought. The numbers are similar to those reported in late November, indicating that while the drought is not getting worse over the winter, conditions are not improving either.

Historically these percentages were surpassed only during the Dust Bowl of the 1930s and a severe drought in the mid-1950s.

Scientists have been warning for years that climate change is increasing the risk of drought, particularly in southern and western portions of the country, and this year’s dry conditions are consistent with predictions of escalating risk.

The drought has devastated crops that are essential to U.S. food production, including corn, soybeans and winter wheat. It has also reduced the abilities of some cities and counties to treat wastewater, affected shipping on one key stretch of the Mississippi River, and driven up global food prices.

In addition to reducing the greenhouse gas emissions causing global warming, Americans need to begin adapting to an increased risk of drought and extreme temperatures.

Rising Risk of Drought

The United States is historically susceptible to drought. Tree ring studies have shown major droughts in the distant past, while some more recent dry periods are still within living memory, such as the Dust Bowl or the drought of the 1950s. These historic examples should serve as guideposts to highlight our vulnerabilities to drought as we move into a drier future.

Scientists have long warned that global warming is increasing the risk of drought, particularly in the Southwest United States. In 2002, parts of the Midwest and Rocky Mountains were hit by drought, while California suffered through a three-year drought toward the end of the decade. In 2011, Texas experienced its driest 12 months ever. At one point, 80 percent of the state was rated at an “exceptional” level of drought. These examples are consistent with the rising risk of drought due to climate change and offer insights into what we can expect from future droughts.

Costs at Home

In the United States, the current drought is the most expansive since 1956, and the impacts are being felt in several areas of the economy. The total cost is estimated at $50 billion to $80 billion.

One of the most severely affected areas is agriculture. The USDA has declared a natural disaster in large portions of Kansas, Colorado, Oklahoma and Texas – states that accounted for one-third of the nation’s wheat crop last year.

The most recent crop reports available, from early December, showed record poor crop conditions for winter wheat, the dominant variety. Analysts predict up to 25 percent of the crop will be abandoned because it is poorly developed, driving up prices that were already high at planting time.

The hardest hit crop is corn. The 2012 harvest of 10.78 billion bushels was only about 75 percent of what the U.S. Department of Agriculture predicted last spring, as 80 percent of U.S. agricultural land was affected.

Ranchers who couldn’t afford feed sold off their herds for the third year in a row, which could mean higher meat prices in future years until herds are replenished. Inevitably, when there is a widespread crop failure, much of the burden falls on the Federal Crop Insurance Corporation, which is owned and subsidized by taxpayers. Insurance payments and high food prices helped gross income grow by 5 percent last year. However, almost $2.7 billion in inventory losses sent net farm income down by more than 3 percent from 2011.

The drought is also having a major impact on the nation’s commerce because of low water levels on the Mississippi River.  Most of the boats that haul barges on the river need at least nine feet of water, but the U.S. Army Corps of Engineers had to blast, dredge and clear obstructions on one key stretch between St. Louis, Mo., And Cairo, Ill., to keep the clearance from dropping too low for most barge traffic. Shippers were forced cut down their loads, rendering the region a virtual ghost town.

The potential supply-chain disruption, according to the American Waterways Operators, could cut significantly into the $2.8 billion worth of good shipped on the river in a typical January, affecting more than 8,000 jobs, as well as more than $54 million in wages and benefits.

At the municipal and county level, some wastewater treatment plants haven’t been able to discharge water into rivers that have flows under the minimum level. Many cities also have water restrictions, such as limits on watering lawns, to preserve remaining water supplies.

Potential Global Problems

With US production down in 2012, corn and soybean prices reached record highs on global markets. Since then, global exporters have taken up some of the slack, backing prices off record levels, although they remain high due to ongoing droughts abroad in other major agricultural regions.

As global drought risk increases, the chances of droughts striking several major breadbasket regions at once also increases, adding to price instability. In countries already facing reduced food security, cost spikes can lead to social unrest, migration and famine. The 2012 price increase represents the third surge in global food prices in the last four years. During the 2007/2008 crisis, the FAO estimated that high food prices increased the number of chronically hungry people in the word by 75 million. While the United Nations Food and Griculture Organization price index is not yet at the levels seen during the 2008 crisis or the February 2011 peak that helped set off the Arab Spring uprisings, there is a risk that prices edge higher as long as the droughts persist. .

How We Can Adapt

As the climate continues to warm, these droughts offer a glimpse of the kinds of events that will become more common. Our governments and businesses must identify the vulnerabilities that these events expose, and take steps to improve resilience. Actions like using water more efficiently and developing more drought-resistant crops will help prepare us for both future droughts and climate change, but continued adaptation, combined with steps to reduce greenhouse gases will be required to cope with the consequences of climate change.