Climate change projected to boost insect activity and crop loss, researchers say

field of corn with setting sun in background — In 2016, the United Nations estimated that at least 815 million people worldwide don’t get enough to eat. Corn, rice and wheat are staple crops for about 4 billion people, and account for about two-thirds of the food energy intake, according to the UN Food and Agriculture Organization.

Scientists have already warned that climate change likely will impact the food we grow. From rising global temperatures to more frequent “extreme” weather events like droughts and floods, climate change is expected to negatively affect our ability to produce food for a growing human population.

But new research shows climate change is expected to accelerate the rate of crop loss due to insects. In a paper published Aug. 31 in the journal Science, a UW-led team of scientists found that insect activity in today’s temperate, crop-growing regions will rise along with temperatures. Researchers project that this activity, in turn, will boost worldwide losses of rice, corn and wheat by 10-25 percent for each degree Celsius that global mean surface temperatures rise. Just a 2-degree Celsius rise in surface temperatures will push the total losses of these three crops each year to approximately 213 million tons.

“We expect to see increasing crop losses due to insect activity for two basic reasons,” said co-lead and corresponding author Curtis Deutsch, a UW associate professor of oceanography. “First, warmer temperatures increase insect metabolic rates exponentially. Second, with the exception of the tropics, warmer temperatures will increase the reproductive rates of insects. You have more insects, and they’re eating more.”