Earth system models (ESM) seek to simulate all relevant aspects of the Earth system. They include physical, chemical and biological processes and aim to provide projections of future climate. The world community of climate scientists has developed a number of very sophisticated models for this purpose and to guide future policy makers in making choices about climate change mitigation and adaptation. The models have different strengths and weaknesses and do not agree exactly.

One area which consumes significant resources in all modelling centres and where increased collaboration could be effective is model evaluation – comparing different versions of the same model, comparing models with data and intercomparing different models.

Assimila is undertaking a study under the auspices of the IS ENES3 (Infrastructure for the European Network for Earth System Modelling (2019 – 2022)) project to look in depth at the evaluation of Earth system models and to make recommendations, based on user surveys, for future development.