title: A potato model intercomparison across varying climates and productivity levels.
abstract: A potato crop multimodel assessment was conducted to quantify variation among models and evaluate responses to climate change. Nine modeling groups simulated agronomic and climatic responses at low-input (Chinoli, Bolivia and Gisozi, Burundi)- and high-input (Jyndevad, Denmark and Washington, United States) management sites. Two calibration stages were explored, partial (P1), where experimental dry matter data were not provided, and full (P2). The median model ensemble response outperformed any single model in terms of replicating observed yield across all locations. Uncertainty in simulated yield decreased from 38% to 20% between P1 and P2. Model uncertainty increased with interannual variability, and predictions for all agronomic variables were significantly different from one model to another (P < 0.001). Uncertainty averaged 15% higher for low- vs. high-input sites, with larger differences observed for evapotranspiration (ET), nitrogen uptake, and water use efficiency as compared to dry matter. A minimum of five partial, or three full, calibrated models was required for an ensemble approach to keep variability below that of common field variation. Model variation was not influenced by change in carbon dioxide (C), but increased as much as 41% and 23% for yield and ET, respectively, as temperature (T) or rainfall (W) moved away from historical levels. Increases in T accounted for the highest amount of uncertainty, suggesting that methods and parameters for T sensitivity represent a considerable unknown among models. Using median model ensemble values, yield increased on average 6% per 100-ppm C, declined 4.6% per °C, and declined 2% for every 10% decrease in rainfall (for nonirrigated sites). Differences in predictions due to model representation of light utilization were significant (P < 0.01). These are the first reported results quantifying uncertainty for tuber/root crops and suggest modeling assessments of climate change impact on potato may be improved using an ensemble approach.
authors.affiliation: Crop Systems and Global Change Laboratory, USDA-ARS, Beltsville, MD, USA.
authors.forename: David H
authors.initials: DH
authors.lastname: Fleisher
authors.affiliation: Crop Systems and Global Change Laboratory, USDA-ARS, Beltsville, MD, USA.
authors.forename: Bruno
authors.initials: B
authors.lastname: Condori
authors.affiliation: Production Systems and the Environment, International Potato Center, Lima, Peru.
authors.forename: Roberto
authors.initials: R
authors.lastname: Quiroz
authors.affiliation: Desert Agriculture and Ecosystem Program, Kuwait Institute for Scientific Research, Safat, Kuwait.
authors.forename: Ashok
authors.initials: A
authors.lastname: Alva
authors.affiliation: Agricultural & Biological Engineering Department, University of Florida, Gainesville, FL, USA.
authors.forename: Senthold
authors.initials: S
authors.lastname: Asseng
authors.affiliation: Production Systems and the Environment, International Potato Center, Lima, Peru.
authors.forename: Carolina
authors.initials: C
authors.lastname: Barreda
authors.affiliation: Department of Agrifood Production and Environmental Sciences, University of Florence, Florence, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Bindi
authors.affiliation: Agricultural & Biological Engineering Department, University of Florida, Gainesville, FL, USA.
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Boote
authors.affiliation: Department of Agrifood Production and Environmental Sciences, University of Florence, Florence, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Ferrise
authors.affiliation: Soil, Crop and Climate Sciences, University of the Free State, Bloemfontein, South Africa.
authors.forename: Angelinus C
authors.initials: AC
authors.lastname: Franke
authors.affiliation: Central Potato Research Institute, Shimla, India.
authors.forename: Panamanna M
authors.initials: PM
authors.lastname: Govindakrishnan
authors.affiliation: Production Systems and the Environment, International Potato Center SSA, Nairobi, Kenya.
authors.forename: Dieudonne
authors.initials: D
authors.lastname: Harahagazwe
authors.affiliation: Agricultural & Biological Engineering Department, University of Florida, Gainesville, FL, USA.
authors.forename: Gerrit
authors.initials: G
authors.lastname: Hoogenboom
authors.affiliation: Centre for Environment Science and Climate Resilient Agriculture, Indian Agricultural Research Institute, New Delhi, India.
authors.forename: Soora
authors.initials: S
authors.lastname: Naresh Kumar
authors.affiliation: Department of Agrifood Production and Environmental Sciences, University of Florence, Florence, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Merante
authors.affiliation: Leibniz Centre for Agricultural Landscape Research, Institute of Landscape Systems Analysis, Müncheberg, Germany.
authors.forename: Claas
authors.initials: C
authors.lastname: Nendel
authors.affiliation: Department of Agroecology, Aarhus University, Tjele, Denmark.
authors.forename: Jorgen E
authors.initials: JE
authors.lastname: Olesen
authors.affiliation: Leibniz Centre for Agricultural Landscape Research, Institute of Landscape Systems Analysis, Müncheberg, Germany.
authors.forename: Phillip S
authors.initials: PS
authors.lastname: Parker
authors.affiliation: Department of Earth and Environmental Sciences, KU Leuven University, Leuven, Belgium.
authors.forename: Dirk
authors.initials: D
authors.lastname: Raes
authors.affiliation: Agricultural & Biological Engineering Department, University of Florida, Gainesville, FL, USA.
authors.forename: Rubi
authors.initials: R
authors.lastname: Raymundo
authors.affiliation: NASA Goddard Institute for Space Studies, New York, NY, USA.
authors.forename: Alex C
authors.initials: AC
authors.lastname: Ruane
authors.affiliation: Biological Systems Engineering, Washington State University, Pullman, WA, USA.
authors.forename: Claudio
authors.initials: C
authors.lastname: Stockle
authors.affiliation: Earth System Science and Climate Adaptive Land Management, Wageningen University and Research Center, Wageningen, The Netherlands.
authors.forename: Iwan
authors.initials: I
authors.lastname: Supit
authors.affiliation: Department of Earth and Environmental Sciences, KU Leuven University, Leuven, Belgium.
authors.forename: Eline
authors.initials: E
authors.lastname: Vanuytrecht
authors.affiliation: Plant Production Systems, Wageningen University and Research Center, Wageningen, The Netherlands.
authors.forename: Joost
authors.initials: J
authors.lastname: Wolf
authors.affiliation: AgWeatherNet Program, Washington State University, Pullman, WA, USA.
authors.forename: Prem
authors.initials: P
authors.lastname: Woli
mesh_terms: D018533:Biomass; D001838:Bolivia; D057231:Climate Change; D003718:Denmark; D008962:Models, Theoretical; D011198:Solanum tuberosum; D014861:Washington
keywords: climate change; crop modeling; model improvement; solanum tuberosum; uncertainty analysis; yield sensitivity