CPH Post

News

Heatwaves threaten future barley harvests warns study

Yields could drop significantly if summer temperatures continue to rise as part of climate change


Heatwaves could reduce the barley harvest (Photo: Colorbox)

August 11, 2014
10:34

by Ray Weaver


Hot summers and heatwaves like those experienced this year could cause the nation’s output of barley and other grains to decline significantly, according to the results of a three-year study by PhD student Catherine Heinz Ingvordsen at DTU. 

Ingvordsen’s experiment created an environment reminiscent of the UN Climate Panel's future scenarios for Denmark, where there could be a temperature increase of as much as five degrees centigrade by 2075 unless there is a dramatic reduction in the worldwide emissions of greenhouse gases. 

Climate chaos
A five-degree increase would drop the average yield of 138 grain varieties by 29 percent.

”For me, it is clearly worrying as we move towards a future with more and more people and an increasing demand for food,” Ingvordsen told Ingeniøren. 

READ MORE: Failed harvests a windfall for nation's farmers

Ingvordsen said that new types of grain need to be developed.

"By developing and examining the types of grain resistant to climate change, we can work to cultivate new types," she explained.

"But it often takes eight to ten years to create a new variety.” 

Worst case
Ingvordsen examined the effect of ‘worst-case’ heatwaves when temperatures stay at around 33 degrees for ten days when the barley is flowering. This scenario resulted in decreased crop yields of 52 percent. 

Other studies have shown that wheat production will also decline significantly if warmer summers continue in Denmark.



Related stories