Future heat waves pose threat to global food supply
The researchers, from the Tyndall Centre at UEA, the Grantham Research Institute for Climate Change and the Environment (London School of Economics and Political Science, London), and Global Environmental and Climate Change Centre (McGill University, Montreal), arrived at their results using the global crop model PEGASUS to simulate crop yield responses to 72 climate change scenarios spanning the 21st century.
The study also identified particular areas where heat waves are expected to have the largest negative effects on crop yields. Some of the largest affected areas are key for crop production, for example the North American corn belt for corn. When the CO2 fertilization effects are not taken into account, the researchers found a net decrease in yields in all three crops, intensified by extreme heat stress, for the top-five producing countries of each crop.
“Our results show that corn yields are expected to be negatively affected by climate change, while the impacts on wheat and soybean are generally positive, unless CO2 fertilization effects have been overestimated,” continued Deryng.
“However, extreme heat stress reinforced by ‘business-as-usual’ reduces the beneficial effects considerably in these two crops. Climate mitigation policy would help reduce risks of serious negative impacts on corn worldwide and reduce risks of extreme heat stress that threaten global crop production.”
‘Global crop yield response to extreme heat stress under multiple climate change futures’ is published in the journal Environmental Letters on March 20, 2014.
Global crop yield response to extreme heat stress under multiple climate change futures
Delphine Deryng, Declan Conway, Navin Ramankutty, Jeff Price and Rachel Warren
Delphine Deryng et al 2014 Environ. Res. Lett. 9 034011