--- Welcome to the official ADCIRCWiki site! The site is currently under construction, with limited information. ---

For general information, see the ADCIRC site, ADCIRC FAQ, or the ADCIRC Wikipedia page. For model documentation not yet available on the wiki, see the ADCIRC site. New content is being continuously added to the ADCIRCWiki, and material from the main ADCIRC site will be gradually transitioned over to the wiki.

Alaskan Winter Storm with Ice

Jump to navigation Jump to search

This example tests ADCIRC version 55 (and beyond). It tests the simulation of the storm tides in a regional Alaska domain under astronomical and atmospheric forcing in November 2011 during a strong winter storm in the presence of sea ice (affecting the surface wind drag)[1]. The results of interest are the global elevations, velocities and meteorology. The test finishes in about 5 minutes in serial ADCIRC for two weeks of simulation. Find the test at the GitHub test suite.


The mesh was generated using the OceanMesh2D Alaska Example_8_AK.m. The domain encompasses the Gulf of Alaska, Bering Sea, and Chukchi Sea with a minimum resolution of 5 km, comprised of 15,876 vertices and 27,757 triangular elements.

Options/Features Tested

  • ICS = 20: Equal-Area cylindrical projection.
  • IM = 513111: Uses the implicit scheme for the linear component of the gravity wave term (computational time step is 4 minutes).
  • NTIP = 2: Equilibrium tide + self-attraction and loading tide (read from a fort.24 file) forcing for 8 tidal constituents.
  • NWS = 14014: Reads from GRIB2 files that specify the global atmospheric forcing and sea-ice concentration (6-hourly CFSv2 reanalysis data). Sea-ice concentration affects the wind drag coefficient[1].
  • WTIMINC = 21600, 21600: First value gives the temporal interval of the GRIB2 met data (6 hours), second value gives the temporal interval of the GRIB2 ice data (6 hours) - these should always be the same.
  • A00, B00, C00 = 0.4, 0.4, 0.2: Ensures that the implicit scheme is stable with a fairly large time step.
  • ESLM = -0.2: Enables the Smagorinsky turbulence closure with a coefficient of 0.2.
  • NOUTGE = 5: Outputs the global elevations into a netCDF4 fort.63 file.
  • NOUTGV = 5: Outputs the global velocities into a netCDF4 fort.64 file.
  • NOUTGM = 5: Outputs the global meteorology into a netCDF4 fort.73 file (pressure) and a netCDF4 fort.74 file (velocity).
  • internal_tide_friction: Spatially varying linear wave drag fort.13 file attribute accounting for energy conversion due to internal tide generation in the deep ocean.
  • &WarnElevControl namelist: Set "WarnElev", the warning elevation level, to 30-m (elevations reach beyond 20-m [default] but remain below 30-m).
  • &metControl namelist: Set "rhoAir", to 1.29193 (density of air at 0 deg C for 1013 mbar); set "WindDragLimit" equal to 0.0025; set "invertedBarometerOnElevationBoundary" to true (in Alaska extremely large-scale low pressure systems persist and cross over the open boundaries, so it is important to have the inverted barometer condition along the elevation specified boundary); set "outputWindDrag" to true.


  1. 1.0 1.1 Joyce, B.R., Pringle, W.J., Wirasaet, D., Westerink, J.J., Van der Westhuysen, A.J., Grumbine, R., Feyen, J., 2019. High resolution modeling of western Alaskan tides and storm surge under varying sea ice conditions. Ocean Model. 141, 101421. doi:10.1016/j.ocemod.2019.101421