title: Consistent negative response of US crops to high temperatures in observations and crop models.
abstract: High temperatures are detrimental to crop yields and could lead to global warming-driven reductions in agricultural productivity. To assess future threats, the majority of studies used process-based crop models, but their ability to represent effects of high temperature has been questioned. Here we show that an ensemble of nine crop models reproduces the observed average temperature responses of US maize, soybean and wheat yields. Each day >30 °C diminishes maize and soybean yields by up to 6% under rainfed conditions. Declines observed in irrigated areas, or simulated assuming full irrigation, are weak. This supports the hypothesis that water stress induced by high temperatures causes the decline. For wheat a negative response to high temperature is neither observed nor simulated under historical conditions, since critical temperatures are rarely exceeded during the growing season. In the future, yields are modelled to decline for all three crops at temperatures >30 °C. Elevated CO2can only weakly reduce these yield losses, in contrast to irrigation.
authors.affiliation: Climate Impacts and Vulnerabilities, Potsdam Institute for Climate Impact Research (PIK), 14473 Potsdam, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Schauberger
authors.affiliation: Department of Agronomy, Iowa State University, Ames, Iowa 50011, USA.
authors.forename: Sotirios
authors.initials: S
authors.lastname: Archontoulis
authors.affiliation: Institute of Meteorology and Climate Research-Atmospheric Environmental Research (IMK-IFU), Karlsruhe Institute of Technology, 82467 Garmisch-Partenkirchen, Germany.
authors.forename: Almut
authors.initials: A
authors.lastname: Arneth
authors.affiliation: International Institute for Applied Systems Analysis, Ecosystem Services and Management Program, Schlossplatz 1, A-2361 Laxenburg, Austria.|Department of Soil Science, Faculty of Natural Sciences, Comenius University in Bratislava, 84215 Bratislava, Slovak Republic.
authors.forename: Juraj
authors.initials: J
authors.lastname: Balkovic
authors.affiliation: Laboratoire des Sciences du Climat et de l'Environnement, Institut Pierre-Simon Laplace (IPSL), 91191 Gif sur Yvette, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Ciais
authors.affiliation: University of Chicago and ANL Computation Institute, Chicago, Illinois 60637, USA.
authors.forename: Delphine
authors.identifier: 0000-0001-6214-7241
authors.initials: D
authors.lastname: Deryng
authors.affiliation: University of Chicago and ANL Computation Institute, Chicago, Illinois 60637, USA.
authors.forename: Joshua
authors.initials: J
authors.lastname: Elliott
authors.affiliation: International Institute for Applied Systems Analysis, Ecosystem Services and Management Program, Schlossplatz 1, A-2361 Laxenburg, Austria.|Department of Geography, Ludwig Maximilian University, 80333 Munich, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Folberth
authors.affiliation: International Institute for Applied Systems Analysis, Ecosystem Services and Management Program, Schlossplatz 1, A-2361 Laxenburg, Austria.
authors.forename: Nikolay
authors.initials: N
authors.lastname: Khabarov
authors.affiliation: Climate Impacts and Vulnerabilities, Potsdam Institute for Climate Impact Research (PIK), 14473 Potsdam, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Müller
authors.affiliation: Institute of Meteorology and Climate Research-Atmospheric Environmental Research (IMK-IFU), Karlsruhe Institute of Technology, 82467 Garmisch-Partenkirchen, Germany.|School of Geography, Earth &Environmental Science and Birmingham Institute of Forest Research, University of Birmingham, Birmingham B15 2TT, UK.
authors.forename: Thomas A M
authors.initials: TA
authors.lastname: Pugh
authors.affiliation: Climate Impacts and Vulnerabilities, Potsdam Institute for Climate Impact Research (PIK), 14473 Potsdam, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Rolinski
authors.affiliation: Climate Impacts and Vulnerabilities, Potsdam Institute for Climate Impact Research (PIK), 14473 Potsdam, Germany.
authors.forename: Sibyll
authors.initials: S
authors.lastname: Schaphoff
authors.affiliation: University of Natural Resources and Life Sciences, Vienna, Feistmantelstrasse 4, 1180 Vienna, Austria.
authors.forename: Erwin
authors.initials: E
authors.lastname: Schmid
authors.affiliation: Laboratoire de Météorologie Dynamique, Institute Pierre-Simon Laplace, 95005 Paris, France.|Sino-French Institute of Earth System Sciences, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
authors.forename: Xuhui
authors.initials: X
authors.lastname: Wang
authors.affiliation: School of International and Public Affairs, Columbia University, New York, New York 10027, USA.
authors.forename: Wolfram
authors.initials: W
authors.lastname: Schlenker
authors.affiliation: Climate Impacts and Vulnerabilities, Potsdam Institute for Climate Impact Research (PIK), 14473 Potsdam, Germany.
authors.forename: Katja
authors.initials: K
authors.lastname: Frieler