The likelihood of extreme temperatures that could affect wheat crop yields has increased significantly in regions of the US and China, according to a new study.

The world is getting hotter, causing shifts in seasonal patterns and increasing the amount of extreme weather such as severe droughts and heat waves, which can affect crop yields and food supplies.

The findings of the new study predict heat waves that happened approximately once every hundred years in 1981 are now likely to happen once every six years in the Midwestern US and once every 16 years in Northeastern China. The work shows the range of conditions that people need to prepare for, even if those conditions haven’t occurred yet.

“The historical record is no longer a good representation of what we can expect for the future,” says Erin Coughlan de Perez, professor at the Friedman School at Tufts University and lead author of the paper in npj Climate and Atmospheric Science. “We live in a changed climate and people are underestimating current day possibilities for extreme events.”

According to the most recent report from the Intergovernmental Panel on Climate Change, the average global surface temperature in the last decade was 1.1 degrees Celsius higher than it was between 1850 and 1900.

The results indicate that both regions have been lucky in recent years. There is an aspect of randomness to weather—a range of possibilities could occur, sort of like when you roll a six-sided die. So far, these regions have been rolling fairly low numbers, ending up with cooler weather than they could have had. But climate change has switched out the die—the highest number is bigger than it used to be. These regions haven’t experienced the full extent of what is possible, and they might not be ready for it.

Read the full article about wheat production and climate change by Taraneh Pettinato at Futurity.