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Ocean sea surface temperature, sea ice thickness and atmospheric total precipitableOcean sea surface temperature, sea ice thickness and atmospheric total precipitable
water on 2014/09/14-00Z from AXIOM-1 high resolution couple reanalysis
Credit: NASA
SSAI researchers have developed the potential first step in a fully coupled atmosphere/ocean/sea ice model. The eXperimental Analysis of sea Ice and Ocean Mesoscale version 1 (AXIOM-1) is an experimental coupled analysis of global ocean and sea ice obtained by assimilating observations of sea surface temperature, sea surface salinity, sea ice concentration and sea surface chlorophyll into a high-resolution configuration of the Geophysical Fluid Dynamics Laboratory Modular Ocean Model-5 coupled to the Los Alamos National Laboratory Community Ice Code sea ice model and to the Global Modeling and Assimilation Office (GMAO) Goddard Earth Observing System Model, Version 5 (GEOS-5) atmospheric model. 

In addition to producing a global high-resolution analysis of the ocean and sea ice system that is in equilibrium with the operational GMAO atmospheric analysis, AXIOM-1 produces coupled model states that could be used to initialize GMAO operational weather forecasts. Until now, operational forecasts have been produced by integrating the GEOS-5 atmospheric model without coupling it to ocean and sea ice models, assuming instead that lower boundary conditions (i.e., sea surface temperature, sea ice concentrations, etc.) will not change significantly over a five-day forecast period. In contrast, model forecasts initialized from the AXIOM-1 coupled analysis would evolve the full atmosphere/ocean/sea ice coupled system. As a result, weather forecast skills could improve significantly, especially when ocean surface conditions may vary rapidly, as can occur, for example, during hurricane season.