#09 Coupling Ice Shelf Cavities into ACME

Abstract

To date and to our knowledge, no climate models have included explicit static sub-ice-shelf cavities and associated calculation of sub-ice-shelf heat and moisture fluxes as part of coupled simulations.  Inclusion of ice shelf cavities and associated processes is (1) a critical first step towards full coupling of the marine-based Antarctic Ice Sheet and (2) a unique scientific capability in its own right.

To address this fundamental gap in coupled climate modeling, we have now implemented a pioneering representation of static ice shelf cavities in ACME.  Ice shelves and associated fluxes are introduced via code modifications and manipulation of the input domain and inter-component mapping, such that:

• Ocean upper pressures capture ocean surface displacement due to overlying ice shelves (see associated poster)

• atmosphere->ocean fluxes are ignored (for G-compset) or diverted to the land model (for B-compset) over ice shelves

• Sea ice is prohibited from entering ice shelf cavities

• Frazil ice is prohibited from forming within ice shelf cavities

• Runoff is routed to the ice shelf calving front instead of the ice sheet grounding line

The capability has been tested in a realistic configuration via both G-compset and B-compset simulations, with preliminary analysis suggesting the implementation of static ice shelf cavities is correct.  G-compset and B-compset simulations are ongoing to address fundamental questions related to numerical stability, equilibration/variability time scales, resolution dependence, and, ultimately validation against extant observational datasets in preparation for application to ice-shelf-cavity-related climate science.  In addition to opening a door to an exciting new realm of coupled climate science, this work will provide the basis for further development associated with a full coupling of the marine-based Antarctic Ice Sheet within the ACME climate model.

This poster focuses on the coupling, mapping files, and interaction between components.  The submission #26 Ocean Cavities Below Ice Shelves is on the numerical methods required to support sub-ice shelf cavities within the ocean model.