Year: 2026
Type: article
Abstract: Accurate simulation of crop evapotranspiration (ET) is critical for water management and for understanding the impacts of climate variability and change. Yet evidence on model skill in simulating ET remains limited, and the sources of error remain poorly understood. Daily simulations from 17 wheat crop models were evaluated against field observations from two sites in semi-arid and Mediterranean environments under water-limited and irrigated conditions. Absolute ET errors were larger under irrigation, but this contrast was substantially attenuated after normalization by observed ET. The larger absolute errors under irrigation were mainly associated with a greater lack-of-correlation component rather than stronger systematic bias, indicating greater day-to-day mismatch between simulations and observations. Differences among ET-demand approaches also tended to be more evident under irrigation, with Priestley–Taylor-based models tending to produce larger errors, although the broad method classes also differed in other model components. Mixed-effects attribution showed that the conditional associations between ET error and climatic factors differed between the two water-supply datasets. Under irrigation, ET simulation error was associated with vapour pressure deficit (VPD), wind speed, radiation, and the component of maximum temperature not linearly explained by VPD, whereas under water-limited conditions meteorological attribution was weaker and observed soil–water status provided additional information. Root-zone soil moisture provided greater model support than shallow or deep soil moisture and modified the association between VPD and ET error. These findings identify atmospheric-demand representation and root-zone water availability as priorities for improving the evaluation and development of crop ET simulations.
Source: in silico Plants
Authors: Chenzhi Wang, Diane Cooke, Xinxin Chen, Jeffrey White, Katja Trachte, Pierre Martre, Senthold Asseng, Frank Ewert, Bruce Kimball, Gerrit Hoogenboom, Steven Evett, André Chanzy, Sébastien Garrigues, Albert Olioso, Karen Copeland, Jean Steiner, Davide Cammarano, Yi Chen, Marianne Crépeau, Roberto Ferrise, Loic Manceau, Thomas Gaiser, Yujing Gao, Sebastian Gayler, Jose Guarin, Tony Hunt, Guillaume Jégo, Gloria Padovan, Elizabeth Pattey, Dominique Ripoche, Alfredo Rodríguez, Margarita Ruiz Ramos, Vakhtang Shelia, Amit Srivastava, Iwan Supit, Fulu Tao, Kelly Thorp, Michelle Viswanathan, Tobias Karl David Weber, Heidi Webber
Institutions: Leibniz Centre for Agricultural Landscape Research, University of Florida, Brandenburg University of Technology Cottbus-Senftenberg, Institut Agro Montpellier, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, Laboratoire d'Ecophysiologie des Plantes sous Stress environnementaux, Technical University of Munich, University of Bonn, Agricultural Research Service, United States Department of Agriculture, Conservation and Production Research Laboratory, European Centre for Medium-Range Weather Forecasts, Écologie des Forêts Méditerranéennes, Kansas State University, Aarhus University, Chinese Academy of Sciences, Institute of Geographic Sciences and Natural Resources Research, University of Chinese Academy of Sciences, Agriculture and Agri-Food Canada, University of Florence, University of Maryland Center for Environmental Science, University of Hohenheim, Goddard Institute for Space Studies, University of Guelph, Agroclim, University of Castilla-La Mancha, Universidad Politécnica de Madrid, Wageningen University & Research, Grassland, Soil and Water Research Laboratory, Julius Kühn-Institut, University of Kassel
Language: English
Subfield: Soil Science
Domain: Life Sciences
SDGs: Zero hunger, Climate action
Open Access status: gold
Estimated APC paid: $2,297
Funders: U.S. Department of Agriculture, Texas Tech University, Kansas State University, Texas A and M University, Ogallala Aquifer Program, European Commission, Department of Science and Technology, Ministry of Science and Technology, India, Deutsche Forschungsgemeinschaft, Chinese Academy of Sciences, Indo-German Science and Technology Centre, Agricultural Research Service, West Texas A and M University, HORIZON EUROPE Framework Programme, Leibniz-Gemeinschaft, National Key Research and Development Program of China, HORIZON EUROPE Marie Sklodowska-Curie Actions
Awards: Advancing integrated risk assessments of cropping systems in sub-Saharan Africa, Improved CarbOn cycle represeNtation through multi-sCale models and Earth obseRvation for Terrestrial ecOsystems, FAIRe Dateninfrastruktur für die Agrosystemforschung, G4282355729, G489415341, G6442697803, G7394758930, G7755276327, G7767944087, G8259387200, G8288757554, Quantifizierung der Reaktionen von Nutzpflanzen auf erhöhte Temperaturen: Treiber und Prozesse
OpenAlex ID: W7213246526