84th AMS Annual Meeting

Tuesday, 13 January 2004: 5:15 PM
Real-Time Ocean Forecasting over the Mediterranean Sea using Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPSTM)
Room 2A
Hao Jin, SAIC, Monterey, CA; and R. Hodur, J. Cummings, X. Hong, and J. Doyle
Poster PDF (1.6 MB)
Real-time ocean forecasting for the Mediterranean Sea is being performed using the ocean components of the Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS). Specifically, a 3-dimensional multivariate optimum interpolation (MVOI) program is used to construct the ocean analysis every 12 hours, and the NRL Coastal Ocean Model (NCOM) is then used to generate ocean forecasts to 72 hours from each analysis. A 12 h incremental data assimilation cycle is used, whereby at each analysis time, the 12 h NCOM forecast from the previous analysis time is used for the first-guess for the current analysis. The analysis increments are then added to the first-guess fields to construct the initial fields for NCOM. Each analysis uses all available observational data, including altimeter SSH, surface ship and buoy SST, XBT and PALACE float profiles, MCSST, and SSM/I sea ice data. NCOM uses a 6 km grid and 40 vertical levels, and is run in a one-way coupled mode, with the surface forcing provided by real-time atmosphere forecasts from COAMPS. The atmosphere forcing fields are generated daily using a doubly-nested grid over the Mediterranean area, with the inner grid using a grid resolution of 27 km. The 27 km resolution forcing fields are saved hourly from the atmospheric model for application as upper boundary conditions for NCOM. The only lateral boundary conditions necessary for the NCOM grid are at the Straits of Gibraltar. Here, climatological input/output values are specified that vary monthly. Output from the COAMPS ocean MVOI/NCOM data assimilation and forecast system, and from the COAMPS atmospheric forcing fields are displayed on a local web server and updated every 12 hours. This display includes surface variables, such as sea surface temperature, currents, height, wind stress, and heat, moisture, and solar fluxes; 3-D variables, including temperature, currents, and salinity; and custom animations of individual forecasts or series of forecasts. The real-time ocean forecast is verified with observational data. This presentation will describe the system configuration and examples and verification of the ocean analyses and forecasts of the system.

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