Climate change impact studies depend on projections of future climate provided by climate models. The selection of an ensemble of climate models is not straightforward, but defines the outcome of climate change impact studies to a large extent. A new approach to select representative climate models was developed by FutureWater in collaboration with Alterra Wageningen UR and ICIMOD, and published recently in the International Journal of Climatology.

Since the number of climate models is large and increasing, limitations in computational capacity make it necessary to compromise the number of climate models that can be included in a climate change impact study. The selection of climate models is not straightforward and can be done by following different methods. Usually, the selection is either based on the entire range of changes in climatic variables as projected by the total ensemble of available climate models or on the skill of climate models to simulate past climate. The new methodology combines these approaches in a selection procedure that combines the projected range of changes in climatic means, climatic extremes, and the climate model skill to simulate past climate. This approach was developed for the Himalayan Adaptation, Water and Resilience (HI-AWARE) project, and is implemented in a climate change impact study for the Indus, Ganges and Brahmaputra river basins.

The study is published in the scientific, peer-reviewed, International Journal of Climatology and can be downloaded (open access) here.