Implications of crop model ensemble size and composition for estimates of adaptation effects and agreement of recommendations

Research output: Contribution to journalArticle

Abstract

Climate change is expected to severely affect cropping systems and food production in many parts of the world unless local adaptation can ameliorate these impacts. Ensembles of crop simulation models can be useful tools for assessing if proposed adaptation options are capable of achieving target yields, whilst also quantifying the share of uncertainty in the simulated crop impact resulting from the crop models themselves. Although some studies have analysed the influence of ensemble size on model outcomes, the effect of ensemble composition has not yet been properly appraised. Moreover, results and derived recommendations typically rely on averaged ensemble simulation results without accounting sufficiently for the spread of model outcomes. Therefore, we developed an Ensemble Outcome Agreement (EOA) index, which analyses the effect of changes in composition and size of a multi-model ensemble (MME) to evaluate the level of agreement between MME outcomes with respect to a given hypothesis (e.g. that adaptation measures result in positive crop responses). We analysed the recommendations of a previous study performed with an ensemble of 17 crop models and testing 54 adaptation options for rainfed winter wheat (Triticum aestivum L.) at Lleida (NE Spain) under perturbed conditions of temperature, precipitation and atmospheric CO2 concentration. Our results confirmed that most adaptations recommended in the previous study have a positive effect. However, we also showed that some options did not remain recommendable in specific conditions if different ensembles were considered. Using EOA, we were able to identify the adaptation options for which there is high confidence in their effectiveness at enhancing yields, even under severe climate perturbations. These include substituting spring wheat for winter wheat combined with earlier sowing dates and standard or longer duration cultivars, or introducing supplementary irrigation, the latter increasing EOA values in all cases. There is low confidence in recovering yields to baseline levels, although this target could be attained for some adaptation options under moderate climate perturbations. Recommendations derived from such robust results may provide crucial information for stakeholders seeking to implement adaptation measures.

Details

Authors
  • A. Rodríguez
  • M. Ruiz-Ramos
  • T. Palosuo
  • T. R. Carter
  • S. Fronzek
  • I. J. Lorite
  • Roberto Ferrise
  • N. Pirttioja
  • Marco Bindi
  • P. Baranowski
  • S. Buis
  • D. Cammarano
  • Y. Chen
  • B. Dumont
  • F. Ewert
  • T. Gaiser
  • P. Hlavinka
  • H. Hoffmann
  • J. G. Höhn
  • F. Jurecka
  • Kurt Christian Kersebaum
  • J. Krzyszczak
  • M. Lana
  • J. Minet
  • Manuel Montesino
  • C. Nendel
  • J. R. Porter
  • Françoise Ruget
  • Mikhail A. Semenov
  • Z. Steinmetz
  • Pierre Stratonovitch
  • I. Supit
  • Fulu Tao
  • M. Trnka
  • A. de Wit
  • R. P. Rötter
Organisations
External organisations
  • Technical University of Madrid
  • University of Castilla La Mancha
  • Natural Resources Institute Finland (Luke)
  • Finnish Environment Institute
  • University of Florence
  • Institute of Agrophysics, PAS
  • University of Bonn
  • Mendel University
  • Academy of Sciences of the Czech Republic
  • Leibniz-Zentrum fur Agrarlandschaftsforschung (ZALF) e. V.
  • Swedish University of Agricultural Sciences
  • University of Liège
  • University of Copenhagen
  • Rothamsted Research
  • Wageningen University
  • University of Göttingen
  • Andalusian Institute of Agricultural and Fisheries Research and Training
  • INRA National Institute of Agricultural Research
  • James Hutton Institute
  • RIFCON GmbH
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Meteorology and Atmospheric Sciences
  • Environmental Sciences related to Agriculture and Land-use

Keywords

  • Climate change, Decision support, Outcome confidence, Response surface, Uncertainty, Wheat adaptation
Original languageEnglish
Pages (from-to)351-362
JournalAgricultural and Forest Meteorology
Volume264
Publication statusPublished - 2019
Publication categoryResearch
Peer-reviewedYes