Climate-induced warming is jeopardizing the global food supply even as farmers take adaptive measures to stymie these effects, scientists are warning.
In contrast with previous research suggesting that warming could actually bolster food production, a new study, published in Nature on Wednesday, finds the opposite.
For every additional degree Celsius the planet warms, its ability to produce food could decrease by 120 calories per person per day, or 4.4 percent of the current daily consumption, according to the study.
“If the climate warms by 3 degrees, that’s basically like everyone on the planet giving up breakfast,” senior author Solomon Hsiang, a professor of environmental social sciences at Stanford University, said in a statement.
Another serious side effect, Hsiang warned, could be price surges that infringe upon access to food for families across the world.
U.S. agriculture is expected to suffer significant losses, particularly in the Midwest, the researchers noted.
Lead author Andrew Hultgren, an assistant professor of agricultural and consumer economics at the University of Illinois Urbana-Champaign, warned that U.S. corn and soybean production could “just get hammered under a high warming future.”
“You do start to wonder if the Corn Belt is going to be the Corn Belt in the future,” Hultgren said in a statement.
Hsiang and Hultgren, together with more than a dozen scholars, worked over the past eight years to draw observations from more than 12,000 regions across 55 countries. They analyzed adaptation costs and yield for crops responsible for two-thirds of the planet’s calories: wheat, rice, soybeans, barley and cassava.
They found that previous studies failed to consider what adaptation measures might be realistic for farmers — assuming that they would implement either “perfect” adaptation protocols or none at all.
The researchers estimated that adjustments farmers are making — such as switching crops, shifting planting and harvesting dates and altering fertilizer — could offset about a third of climate-related losses in 2100 amid rising emissions.
But the rest of the losses, they stressed, would remain.
“Any level of warming, even when accounting for adaptation, results in global output losses from agriculture,” Hultgren said.
Overall, the researchers found that yield losses could amount to about 41 percent in the wealthiest regions and 28 percent in lowest income areas by 2100.
There is a 50 percent chance that the world’s rice yields could rise, because rice thrives on warm nights, while there is a 70 to 90 percent chance that the other staple crops will decline, according to the study.
In the shorter-term, the authors estimated that climate change would bring down global crop production by about 8 percent by 2050, regardless of the rise or fall of emissions. This is because carbon dioxide emissions, they explained, stay in the atmosphere, trapping heat for the long haul.
Going forward, the scientists said they are working with the United Nations Development Program to raise awareness about their findings among governments. They are also creating a system to determine which communities are most at risk of declines and could benefit from targeted support.
“Farmers know how to maintain the soil, invest in infrastructure, repair the barn,” Hsiang said. “But if you’re letting the climate depreciate, the rest of it is a waste. The land you leave to your kids will be good for something, but not for farming.”