Researchers in Denmark, who have looked at different independently produced modelling scenarios for climate change, have said all three come to the same bleak conclusion: rising temperatures will push down wheat yields.

Wheat is the world’s third most widely produced cereal crop (after rice and maize), and the main arable crop for temperate regions. However, experts have said that yields, currently plateauing, are set to drop off as climate change advances, a process which is very much underway; 2016 is set to be the Earth’s warmest year since records began. Each of the three years since 2014 have broken records for the world’s warmest, and every year since the millennium has been in the 17 warmest on record (with 1998 being the only year from last century in the list).

Scientists from an international team, including Professor Joergen E. Olesen and Dr Mohamed Jabloun from the Department of Agroecology at Aarhus University, Denmark looked at three different models for climate change and wheat production. This enabled them to give even more precise projections of the relation between global warming and declining yields.

Two of the models they looked at were simulations, and the third was based on statistical data analyses (from countries’ wheat production statistics, temperature, pest and disease and rainfall records); all used different methods, and were useful for looking at different variables that could affect wheat production. The researchers said models unanimously demonstrate that for each 1°C that the global temperature increases, the global wheat production is projected to decline by an average of 5.7 percent.

Warmer regions suffer the most

Depending on the model used, expected wheat yields are set to decline by between 4.1 and 6.4 percent with each 1°C global temperature increase. Warmer regions are most likely to experience the greatest decline in wheat yield.

This projected impact was similar for major wheat-producing countries such as China, India, USA and France but less so for Russia due to the generally cooler conditions of Russia's wheat-producing areas.

“When talking about global food security it is important to understand how climate change will impact crop production at a global level in order for us to develop fact-based mitigation and adaptation strategies,” said prof Olesen. “By combining several models we were able to improve the confidence of the estimates in relation to climate change impact on global food security.”