Extreme Heat Waves May Be Damaging Wheat Crops, Study Warns

The study indicates that the likelihood of heat waves capable of impacting crop yields has significantly risen in these areas, with once-in-a-century events now projected to occur once every six years in the Midwestern US and once every 16 years in Northeastern China.

The findings emphasize the need for preparedness as seasonal patterns continue to shift and extreme weather events become more frequent.

"The historical record is no longer a good representation of what we can expect for the future," stated lead author Erin Coughlan de Perez, Dignitas Associate Professor at the Friedman School.

She stressed that people are underestimating the possibilities of extreme events in today's changed climate.

The study employed an approach known as the Unprecedented Simulated Extreme Ensemble (UNSEEN) to estimate the frequency of extreme temperatures exceeding critical growth thresholds for wheat. By generating thousands of potential temperature and rainfall variations, the researchers were able to assess the risk to wheat crops. High temperatures during the spring flowering stage can impede the plant's development, leading to heat stress and enzyme breakdown.

The results demonstrate a shift in the risk profile of extreme weather events. "In the Midwest, we used to have seasons where you'd see an average of maybe four or five days of that enzyme breakdown threshold being exceeded—it was pretty uncommon," explained Coughlan de Perez. "But our research showed possible alternative realities of today's climate that generated 15 days above this threshold, which we surmise would be very damaging."

The study also highlights the connection between record-breaking heat and drought, which, when combined, pose a significant threat to the growing season. Both the United States and China are key global breadbaskets, responsible for producing substantial quantities of grains. The simultaneous failure of these crops, along with other staple crops, could have far-reaching consequences on global food prices and availability.

The researchers caution that recent luck with milder weather has masked the full extent of what could occur. Climate change has altered the odds, increasing the potential severity of heat waves. The study calls for proactive planning and preparedness measures.

"Maybe you won't roll an eight for a while, but I think it's worth having some plans in place for when that happens," added Coughlan de Perez.

Additionally, the study identifies regional and global atmospheric circulation patterns that could lead to highly unfavorable hot and dry events, potentially affecting wheat production in both the US and China simultaneously. The findings aim to inform climate adaptation strategies and ensure stakeholders are better equipped to handle future unprecedented events.

Coughlan de Perez stressed the importance of imagination in tackling climate change. "If we're not imagining the kinds of extremes that could happen, then we won't prepare for them," she emphasized.

The study encourages the utilization of available tools and resources to understand the possibilities and to be ready for the challenges ahead.