The Inter-Sectoral Impact Model Intercomparison Project

ISIMIP is a community-driven climate-impacts modelling initiative aimed at contributing to a quantitative and cross-sectoral synthesis of the differential impacts of climate change, including the associated uncertainties. ISIMIP offers a consistent framework for cross-sectoral, cross-scale modelling of the impacts of climate change. The key goal of ISIMIP is to contribute to the comprehensive (cross-sectoral) understanding of the impacts of politically and scientifically-relevant climate-change scenarios.
ISIMIP is organised into simulation rounds, which are guided by a focus topic. For each round, a simulation protocol defines a set of common simulation scenarios based on the focus topic. Participating modelling groups are provided with a common set of climate input data, and other data (in some cases unique to one sector) necessary to ensure cross-sectorally consistent impacts simulations. Participation is open to all models capable of following the simulation protocol.

The ISIMIP3 simulation round has started with the release of the ISIMIP3a and 3b protocols on 21 February 2020. It follows the long-term goal of harmonizing input data for a growing number of sectors. As a new sector, the fire sector has been included. The ISIMIP3a protocol focuses on i) impact model evaluation and improvement and ii) detection and attribution of observed impacts according to the framework of the IPCC WGII-AR5 Chapter 18 definition. As a major update, it thus includes a counterfactual “no-climate change baseline” (detrended climate + observed socio-economic forcing). The ISIMIP3b protocol is dedicated to a quantification of climate-related risks at different levels of climate change and socio-economic conditions. A particular focus is put on providing socioeconomic forcing data that account for different adaptation scenarios (group III simulations). Simulations that include future changes of socioeconomic drivers are intended to start in summer 2021.