Several large ensemble model simulations, either from Global Climate Models (GCM), Earth System Models (ESM), or Regional Climate Models (RCM), have been generated over the recent years. These ensembles, typically simulating historical climate and making future projections, are powerful because they can be used to accurately estimate forced changes in the climate system and to determine the magnitude and realism of simulated internal climate variability. They can further be applied to investigate how climate change signals may emerge from internal variability over time. Combining large ensemble simulations also provides long time series to investigate the dynamics of hydro-meteorological extremes and to assess compound events (e.g., successive or simultaneous extreme events) under conditions of climate change.

This session invites studies using large GCM, ESM, or RCM ensembles looking at the following topics: 1) forced changes in internal variability and reinterpretation of observed record; 2) development of new approaches to attribution of observed events or trends; 3) impacts of natural climate variability; 4) assessment of extreme event occurrence in historical and future climate; 5) development of projections for compound events; 6) comparison of large ensembles including uncertainty assessment; and 7) novel methods for efficient analyses and post-processing of large ensembles.

We welcome research across the components of the Earth system and particularly invite studies that apply novel methods or cross disciplinary approaches to leverage the potential of large ensembles.