GOMEX 3-D Operational Ocean Forecast System Pilot Project
Sponsor: Research Partnership to Secure Energy for America
Portland State University: Christopher Mooers
University of California, Los Angeles: Yi Chao
August 2009 – January 2011
We used the Regional Ocean Modeling System (ROMS) for this Gulf of Mexico (GoM) data assimilation and forecasting system. ROMS is a new community ocean circulation model that is in widespread use for estuarine, shelf, and coastal applications. Its computational kernel includes high-order advection and time-stepping schemes, weighted temporal averaging of the barotropic mode to reduce aliasing into the slow baroclinic motions, and conservative parabolic splines for vertical discretization.
The GoM model configuration used the South Atlantic Bight and Gulf of Mexico Circulation Nowcast/Forecast (SABGOM N/F) Modeling System developed, operated and maintained by Dr. Ruoying He’s group at North Carolina State University. The spatial resolution of this operational SABGOM N/F system is 5 km. Vertically, it has 36 layers weighted to better resolve surface and bottom boundary layers. Currently, the N/F system is using the open boundary condition from the operational 1/12 degree global data assimilative HYCOM NCODA analysis. Surface forcing is obtained from NOAA's National Operational Model Archive and Distribution System (NOMADS). We worked closely with Dr. Yi Chao of UCLA to implement a 3-dimensional variational data (3DVAR) assimilation scheme into the GoM ROMS.