Ice Sheet Model Intercomparison for CMIP6 (ISMIP6) endorsed by CMIP6

-Contributed by Sophie Nowicki.

ismip6The Ice Sheet Model Intercomparison for CMIP6 (ISMIP6) is a CliC targeted activity established in Autumn 2014 with the aim of integrating modelling of the ice sheets into the next phase of the international Coupled Modelling Intercomparison Project (CMIP6) so that projections of mass budget (hence of sea level) are more readily available for the next IPCC. Recently, we received the fantastic news that ISMIP6 has been formally endorsed by CMIP. This will greatly aid the collaboration between the ice-sheet community and those working on other aspects of the coupled climate system. In particular, it will ensure the coordinated provision of climate forcing data for the ice sheets, and focus attention on the quality of climate simulation over (and around) the ice sheets.

Over the year, ISMIP6 has been making steady progress. Important developments include an initial workshop held at NASA Goddard Space Flight Center 16-18th July 2014 (supported by CliC) at which the ISMIP6 concept was discussed with the ice sheet and climate modelling communities. An important outcome was the recognition that two strands of modelling would be necessary: fully coupled in which the ice sheet model sits within a larger climate model and is fully coupled to it; and stand-alone in which ice sheet models are forced by the output of climate models (but are not explicitly coupled to them). The former will focus on Greenland, while the latter will involve both ice sheets. It was felt that fully-coupled modelling is not currently feasible for Antarctica because of uncertainties in both the oceanic forcing and ice-dynamic response of the ice sheet.

A Steering Committee has since been formed and has been working towards a first intercomparison exercise with the aim of developing community engagement from at an early stage. The committee comprises: co-chairs Sophie Nowicki, Eric Larour and Tony Payne with Bill Lipscomb, Heiko Goelzer, Ayako Abe-Ouchi, Andrew Shepherd, Helene Seroussi and Jonathan Gregory. Initial ideas for this exercise were discussed at the EGU in a splinter meeting organised by Heiko and Tamsin Edwards. The final experimental design will be agreed at the forthcoming International Glaciological Society symposium in Cambridge (August 16th-21st) with results presented at the Fall AGU. The theme for this intercomparison will be the methods of model initialisation and their effect on projections.

See more information on the upcoming ISMIP6 meeting at the IGS Symposium in Cambridge in Augsut 2015 here.