MISOMIP is conceived as a series of community exercises involving coupled ice sheet-ocean models, progressing from relatively idealized experiments to realistic experiments of the West Antarctic Ice Sheet (WAIS) region. The first MISOMIP experiment, MISOMIP1, is in essence the combination of MISMIP+ and ISOMIP+ experiments.
MISOMIP1 prescribes that the ice sheet is initially in steady state with no melting, as in MISMIP+. Consistent with this, the initial conditions for the ocean model are cold enough to produce low melt rates (of order 0.2 m/yr on average). For the first 100 years of the simulation, the ocean’s temperature and salinity are restored in the far field to a warm profile consistent with Circumpolar Deep Water in the Amundsen Sea Embayment. This warm water is expected to be advected into the ice-shelf cavity within less than a decade, at which point it induces strong melting and subsequent rapid ice retreat. After 100 years, the far-field restoring in the ocean model is abruptly switched to a colder profile at the surface freezing temperature. This will shut off melting over the subsequent decade and allow ice to re-advance for the next 100 years.
Bathymetry is the same as for MISMIP+ and ISOMIP+. All ice-sheet parameters are the same as for MISMIP+ except for basal melting, which is computed by the coupled system in MISOMIP1 rather than being parameterized, and that a thickness-based calving parameterization is applied. The ice-sheet initial condition should be identical to MISMIP+ except for calving parameterization. The initial state of the ocean and forcing is the same as in ISOMIP+ Experiment 1 (COLD initial profile, WARM restoring profile).
A complete description of the experiments will be published in an article in Geoscientific Model Development, to be submitted in July, 2015.
Example output from POP2x runs includes movies and figures. Example NetCDF results are coming soon.