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Home > ESTOFS Global documentation

The Global Extratropical Surge and Tide Operational Forecast System (ESTOFS Global) provides users with nowcasts (analyses of near present conditions) and forecast guidance of water level conditions for the entire globe. The forecast outputs include water levels caused by the combined effects of storm surge and tides, by astronomical tides alone, and by sub-tidal water levels (isolated storm surge) out to 180 hours. The hydrodynamic model employed by ESTOFS Global is the ADvanced CIRCulation (ADCIRC) finite element model. The unstructured grid used by ESTOFS Global consists of 8,063,409 nodes and 15,478,900 triangular elements. Coastal resolution is up to 80 m for Hawaii and the U.S. West Coast; up to 90-120 m for the Pacific Islands including Guam, American Samoa, Marianas, Wake Island, Marshall Islands, and Palau; and up to 120 m for the U.S. East Coast, Puerto Rico, Micronesia, and Alaska. The flood plain extends overland to approximately 6 m elevation ASL for the U.S. East Coast, and up to 20 m elevation ASL for the Pacific Islands. ESTOFS Global: reduces bias and errors due to the removal of the open ocean boundary; includes internal tides; includes sea-ice effect on wind drag, and incorporates a bias correction using 2-day average water level anomalies (observations minus tidal predictions) calculated at CO-OPS tide stations and interpolated spatially across the ESTOFS Global mesh.
ESTOFS Global output files are provided here in two formats: structured GRIB2 files for the contiguous U.S. East region (2.5 km resolution), contiguous U.S. West region (2.5 km resolution), Alaska (6 km resolution), Hawaii (2.5 km resolution), Guam (2.5 km resolution), North Pacific (10 km resolution), and Puerto Rico (1.25 km resolution) grids, and unstructured NetCDF files on the native ESTOFS Global finite element grid, consisting of ~8 million nodes. NetCDF output is also provided at 558 observation station locations globally. GRIB2 files are created for hourly forecasts during each forecast cycle, consisting of hourly records of combined water level (surge with tide), harmonic tidal prediction (astronomical tides), and sub-tidal water levels (the isolated surge). There are also GRIB2 files that contain an entire run cycle, for each of combined, harmonic tidal prediction, and sub-tidal water levels. NetCDF files contain an entire run cycle, and consist of the hourly combined, harmonic tidal prediction, and sub-tidal water levels over the native ESTOFS Global grid, or six-minute combined, harmonic tidal prediction, and sub-tidal water level records at observation station locations.

ESTOFS web page:
Storm Surge


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