The atmospheric response to sea-ice loss in the PAMIP experiments and its sensitivity to model biases

Polar amplification, the phenomenon that external radiative forcing produces a larger change in surface temperature at high latitudes than the global average, is a key aspect of anthropogenic climate change, but its causes and consequences are not fully understood. The Polar Amplification Model Intercomparison Project (PAMIP) seeks to improve our understanding of this phenomenon through a coordinated set of numerical model experiments. As one of the Coupled Model Intercomparison Project Phase 6 (CMIP6) endorsed MIPs, PAMIP addresses the how the global climate system responds to changes in Arctic and Antarctic sea ice. The PAMIP community will convene for a remote workshop in late March to share scientific results and to facilitate/foster collaborative studies based on the PAMIP multi-model experiment database. The workshop will inspire the choice of priority topics for focussed attention during the CMIP6 Hackathon, with a view toward accelerating the analysis and publication of the PAMIP multi-model experiments. Early results from the PAMIP suggest that the atmospheric response to future sea-ice loss is model dependent, particularly in the stratosphere. One focus of analysis will be attempting to explain the diversity in the response to sea-ice loss across CMIP6 models to model biases, particularly in the upper troposphere and lower stratosphere.