The term Anthropocene denotes the on-going time period since the beginning of the industrialisation. Human actions have changed the Earth’s climate and environment during this period. 

How can the changes up to now be quantified and how to prepare for the future? 

Earth system models (ESMs) are key tools to answer this question. They are climate models which next to physics also take into account chemical, biological, and ecosystem processes. 

In EVA, the Norwegian Earth system model (NorESM) as the main national facility for global climate studies will be further developed, extended, quality checked, and applied to key research questions in the field of climate science. In particular, NorESM2 will be established also for participation in key international assessments. 

NorESM experiments on drivers for climate variability will be carried out, and related feedbacks will be quantified addressing key uncertainties. Complex spatio-temporal structures of the climate system will be analysed including interactions between physical processes and biogeochemical cycles. The planned pre-industrial, historical, and future NorESM simulations together with observational evidence provide the foundation for discriminating between natural and human-induced climate variability. 

More complete process representations in NorESM on the basis of observational evidence and a detailed model evaluation against observations will enable more realistic quantifications of uncertainties in state-of-the-art climate simulations. Relevant Arctic climate processes will be addressed: cold clouds, Arctic haze, sea-ice and permafrost thawing. 

EVA is firmly embedded within the international scientific research field. NorESM is provided as a major national infrastructure for large-scale predictive climate studies. Results and data sets will be open to all end-users (scientists, policy makers, and the public). For adaptation and mitigation purposes, data will be made available through the National Climate Service Centre.