A 'Second Dust Bowl' Could Trigger Worldwide Food Shortages and Price Hikes, Study Suggests

A second Dust Bowl could have a rippling effect on food security and prices affecting not just the U.S. but the entire world, say scientists writing in the journal Frontiers in Sustainable Food Systems.

In the 1930s, an atypical La Niña triggered a period of severe drought, strong winds, and above-average temperatures in the American Great Plains. The soil was already degraded from decades of overuse. But the La Niña was the final straw, causing intense dust storms and widespread crop failure that lasted several years.

The country's wheat and maize production plummeted, dropping 36 and 48 percent respectively over the course of the 1930s.

Although there have been several severe droughts since, the Ogallala aquifer, which runs beneath the Great Plains region, has helped buffer the effects by supplying irrigated water to the region. But what would happen if the U.S. was hit by a similar shock in the future?

That is the question behind a new study, looking at how "a second Dust Bowl" — equivalent in scale to its namesake — would affect the U.S. and the world.

"In today's system of global food trade, disruptions are not bound by borders," lead author Dr. Alison Heslin, a postdoctoral researcher at the Center for Climate Systems Research of Columbia University and NASA's Goddard Institute for Space Studies, said in a statement.

"Shocks to production are expected to affect trade partners who depend on imports for their domestic food supply."

Large dust cloud appears behind a truck
South of Lamar, Colorado, a large dust cloud appears behind a truck traveling on highway 59, May 1936. A similar event would have a large impact on the world's food supply, scientists say. PhotoQuest/Getty

Heslin and colleagues used computer models to see how a Dust Bowl-like event would impact food chains across the world today. The researchers used historical data on wheat production, trade and reserves to establish a baseline. They then applied a "shock" and watched how it rippled out, impacting trade and wheat supplies in the U.S. and across the world.

Shortages, they say, could be addressed in two ways. They can be absorbed at the national level, with countries using up reserves or reducing consumption. Or they can be shared among trading partners by lowering the number of exports and upping the number of imports.

In one model, countries adjust their imports and exports at the same time, increasing imports from countries without shortages and decreasing exports with all trading partners equally. In this sense, the shock is absorbed by exports and imports.

In the second, more complicated simulation, the U.S. reduces exports only. The shock ripples "downstream" to trading partners who would typically receive imports from the U.S.. From this point, countries with a shortage respond by upping their imports.

The models show that not only would an event like this devour 94 percent of the U.S.' reserves in just four years, it would — without exception — cause each of the countries that receive U.S. imports to deplete their reserves. This is despite the fact that not one of them suffered their own crop failure. In short, a national agricultural event would have a global impact.

A four-year event like the Dust Bowl could trigger an initial 31 percent drop in the world's wheat supplies. On a national level, the study suggests at least 36, and as many as 52, countries could use up more than three-quarters of the reserves they had at the start within four years. Even the ten countries with the highest reserves at the start of the simulation, including China, USA, India, and Iran, could see stocks deplete as much as 15 to 22 percent.

"This suggests that the impacts would not only raise prices for US consumers but would also raise prices far beyond the US borders," said co-author Dr. Jessica Gephart, Assistant Professor at the Department of Environmental Science of the American University in Washington, D.C.

As the researchers point out, their simulations were based on a production shock that only directly affects one country — in this case, the U.S. In reality, as global temperatures rise, the chances of of multiple production shocks taking in different countries at the same time is likely to increase.

"In such an event, with multiple producing countries decreasing exports, the trade system would exhaust available reserves, and countries would face consumption declines," they write.

The authors also note that the study doesn't take into account factors like price increases, which could impact trade activity, or "other actor responses" such as hoarding, which may further impact the supply chain and create additional shortages.

There is, however, some good news. The models suggest that in most cases production shocks and food shortages can be addressed by adjusting the flow of trade.

Abandoned Farms During the Dust Bowl
Picture shows an abandoned farmstead in the dust bowl in 1937 Oklahoma. Bettmann/Getty