Rising temperatures reduce global wheat production

Authors: ASSENG, S - University Of Florida; EWART, F - University Of Bonn; MARTRE, P - Institut National De La Recherche Agronomique (INRA); ROTTER, R - Mtt Agrifood Research Finland; LOBELL, D - Stanford University; CAMMARANO, D - University Of Florida; Kimball, Bruce; OTTMAN, M - University Of Arizona; Wall, Gerard - Gary; White, Jeffrey; REYNOLDS, M - International Maize & Wheat Improvement Center (CIMMYT); ALDERMAN, P - International Maize & Wheat Improvement Center (CIMMYT); PRASAD, P - Kansas State University; AGGARWAL, P - International Water Management Institute; ANOTHAI, J - Washington State University; BASSO, B - Michigan State University; BIERNATH, C - German Research Center For Environmental Health; CHALLINOR, A - University Of Leeds; DE SANCTIS, G - Institut National De La Recherche Agronomique (INRA); DOLTRA, J - Center For Agricultural Research And Training, Cantabria Government (CIFA); FERERES, E - Universidad De Cordoba; GAYLER, S - University Of Tubingen; HOOGENBOOM, G - Washington State University; HUNT, L - University Of Guelph; IZAURRALDE, R - University Of Maryland; JABLOUN, M - Aarhus University; JONES, C - University Of Maryland; KERSEBAUM, K - Institute Of Landscape Systems Analysis, Leibniz Centre For Agricultural Landscape Research; KOEHLER, A - University Of Leeds; MULLER, C - Potsdam Institute; NARESH KUMAR, S - Indian Agricultural Research Institute; NENDAL, C - Institute Of Landscape Systems Analysis, Leibniz Centre For Agricultural Landscape Research; O'LEARY, G - Department Of Primary Industries; OLESEN, J - Aarhus University; PALOSUO, T - Mtt Agrifood Research Finland; PRIESACK, E - German Research Center For Environmental Health; EYSHI REZAEI, E - University Of Bonn; RUANE, A - Goddard Space Flight Center; SEMENOV, M - Rothamsted Research; SHCHERBAK, I - Michigan State University; STEDUTO, P - Food & Agriculture Organization (FAO); STOCKLE, C - Washington State University; STRATONOVITCH, P - Rothamsted Research; STRECK, T - University Of Hohenheim; SUPIT, I - Wageningen University; TAO, F - Mtt Agrifood Research Finland; THORBURN, P - Commonwealth Scientific And Industrial Research Organisation (CSIRO); WAHA, K - Potsdam Institute; WANG, E - Commonwealth Scientific And Industrial Research Organisation (CSIRO); WALLACH, D - Institut National De La Recherche Agronomique (INRA); WOLF, J - Wageningen University; ZHAO, Z - China Agricultural University; ZHU, Y - Nanjing Agricultural University

Submitted to: Nature Climate Change
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/18/2014
Publication Date: 12/22/2014
Citation: Asseng, S., Ewart, F., Martre, P., Rotter, R.P., Lobell, D.B., Cammarano, D., Kimball, B.A., Ottman, M.J., Wall, G.W., White, J.W., Reynolds, M.P., Alderman, P.D., Prasad, P.V., Aggarwal, P.K., Anothai, J., Basso, B., Biernath, C., Challinor, A.J., De Sanctis, G., Doltra, J., Fereres, E., Gayler, S., Hoogenboom, G., Hunt, L.A., Izaurralde, R.C., Jabloun, M., Jones, C.D., Kersebaum, K.C., Koehler, A.K., Muller, C., Naresh Kumar, S., Nendal, C., O'Leary, G., Olesen, J.E., Palosuo, T., Priesack, E., Eyshi Rezaei, E., Ruane, A.C., Semenov, M.A., Shcherbak, I., Steduto, P., Stockle, C., Stratonovitch, P., Streck, T., Supit, I., Tao, F., Thorburn, P., Waha, K., Wang, E., Wallach, D., Wolf, J., Zhao, Z., Zhu, Y. 2014. Rising temperatures reduce global wheat production. Nature Climate Change. 5:143-147.

Interpretive Summary: Computer simulations are widely used to assess the potential threats of climate change on food production, but the accuracy of such models has not been systematically tested against field experiments involving high temperature conditions. This paper describes comparisons among 30 different wheat crop simulation models using data from field experiments in which wheat was exposed to growing season mean temperatures ranging from 15 to 32 °C, including experiments with artificial heating. Many of the models simulated yields well, but predictions diverged at higher temperatures. In testing whether using a group of models, termed an “ensemble”, would give more accurate estimates, the median value from all models was more accurate in describing temperature response than any single model, regardless of available input information. Extrapolating the ensemble's temperature response indicated global wheat production would decline 6% for each degree centigrade of global warming. This trend was associated with increased variability of yield regionally and over time. To reduce future potential yield losses, breeding for wheat varieties that have a longer period of grain filling or delay maturity and that tolerate high temperatures will be critical.

Technical Abstract: Crop models are essential to assess the threat of climate change for food production but have not been systematically tested against temperature experiments, despite demonstrated uncertainty in temperature response. Herein, we compare 30 different wheat crop models against field experiments in which wheat was exposed to growing season mean temperatures ranging from 15 to 32 oC, including experiments with artificial heating. Many models simulated yields well, but model disagreement increased at higher temperatures. The model ensemble median was consistently more accurate in simulating temperature response than any single model, regardless of available input information. Extrapolating the ensemble's temperature response indicated global wheat production losses of 6% for each degree centigrade of global warming, with increased variability of yield in space and time. To reduce potential yield losses, breeding for increased grain filling duration or delayed maturity combined with heat tolerance in wheat will be critical.