This site contains hindcasts and real-time nowcast/forecast results from the 1/12° Global HYCOM+CICE System, including snapshots animations and forecast verification statistics for many zoom regions of sea surface height (SSH), sea surface temperature (SST), sea surface salinity (SSS), sea ice concentration, sea ice thickness, and sea ice speed and drift,

The Los Alamos sea ice model (CICE) (Hunke and Lipscomb, 2008) is coupled with the HYbrid Coordinate Ocean Model (HYCOM) (Chassignet et al., 2009). Sea ice and ocean fields are passed between the two models hourly using Earth System Modeling Framework (ESMF) (Hill et al., 2004). The sea ice and ocean models are set up and coupled on the same 1/12° global tripole grid. Horizontal resolution is approximately 3.5 km near the North Pole and 6.5 km near 40°N. Atmospheric forcing is obtained from the Fleet Numerical Meteorology and Oceanography Center 3 hrly 0.281° NAVy Global Environmental Model (NAVGEM).

The data assimilation is performed once a day using the Navy Coupled Ocean Data Assimilation (NCODA) (Cummings, 2005) system with a model forecast as the first guess. NCODA assimilates available satellite altimeter observations (along track obtained via the NAVOCEANO Altimeter Data Fusion Center), satellite sea ice concentration, satellite and in situ SST as well as available in situ vertical temperature and salinity profiles from XBTs, Argo floats and moored buoys using a 3-Dimensional VARiational analysis (3DVAR) scheme.

Data fields will be available for download from hycom.org.

For more information see (Cummings and Smedstad, 2013) and (Metzger et. al., 2014).

References

Chassignet, E.P., H.E. Hurlburt, E.J. Metzger, O.M. Smedstad, J.A. Cummings, G.R. Halliwell, R. Bleck, R. Baraille, A.J. Wallcraft and C. Lozano, 2009: US GODAE Global Ocean Prediction with the HYbrid Coordinate Ocean Model (HYCOM). Oceanography vol 22, 64-75.

Cummings, J.A., 2005: Operational multivariate ocean data assimilation. Quart. J. Royal Met. Soc., Vol. 131, pp 3583- 3604.

Cummings J.A. and O. M. Smedstad. 2013: Variational Data Assimilation for the Global Ocean. Data Assimilation for Atmospheric, Oceanic and Hydrologic Applications vol II, chapter 13, 303-343.

Hill, C., C. DeLuca, V. Balaji, M. Suarez, A. da Silva, 2004: The Architecture of the Earth System Modeling Framework. Computing in Science and Engineering, Vol. 6, pp 18-28.

Hunke, E.C. and W. Lipscomb, 2008: CICE: The Los Alamos sea ice model, documentation and software user's manual, version 4.0. Tech. rep. LA-CC-06-012, Los Alamos National Laboratory, Los Alamos, NM. (http://oceans11.lanl.gov/drupal/CICE).

Metzger, E.J., O.M. Smedstad, P.G. Thoppil, H.E. Hurlburt, J.A. Cummings, A.J. Wallcraft, L. Zamudio, D.S. Franklin, P.G. Posey, M.W. Phelps, P.J. Hogan, F.L. Bub and C.J. DeHaan, 2014: US Navy operational global ocean and Arctic ice prediction systems. Oceanography, 27(3), 32--43, http://dx.doi.org/10.5670/oceanog.2014.66.