Extreme Midwest Droughts May Risk Corn and Soybean Crops in the Next Half-Century

Droughts in the Midwest are becoming a serious concern. Now, scientists have taken a closer look at weather patterns, and have found that increasingly harsh drought conditions may take a serious toll on corn and soybean yields over the next half-century.

The U.S. corn and soybean crops account for about 40 and 35 percent of global production, respectively. This makes any risk to these crops in the U.S. a threat to global food security. That's why scientists decided to take a closer look at the possible impacts that we may see in the future if droughts continue to remain a problem.

The scientists examined field data over an 18-year period. More specifically, they pointed toward the effects of vapor pressure deficit (VPD) on corn and soybean yields. VPD includes temperatures and humidity measures; extremes at either end signify too much drought or too much water.

So what did they find? It turns out that corn yields could drop by 15 to 30 percent, while soybean losses could be less severe.

"Yield increases are getting smaller in bad conditions," said Roderick Rejesus, one of the researchers, in a news release. "Agronomic and genetic crop improvements over the years help a lot when growing conditions are good, but have little effect when growing conditions are poor, like during droughts."

In fact, the researchers estimate that VPD will rise significantly over the next 40 years. This means more drought conditions, which means poorer growing conditions for crops. It's important in particular for farmers to take this into account when planting.

"There are a number of risk management implications for farmers," said Rejesus in a news release. "Should farmers-80 percent of whom already purchase crop insurance-buy even higher levels of crop insurance? What kinds of safety nets should be in place for farmers, if any? What happens to meat prices when corn yields diminish? There are lots of tradeoffs involved in this issue."

The findings are published in the journal Science.