Assimilation of HF radar-derived radials and total currents in the Monterey Bay area
Paduan, Jeffrey D.
MetadataShow full item record
Impact of HF radar surface-current assimilation on ocean circulation model predictions in the Monterey Bay area is studied and evaluated during the time frame of the Autonomous Ocean Sampling Network (AOSN-II) experiment (August-September 2003). In the first instance, a previously described method for assimilation of surface current data is applied to 33-h low-pass-filtered data and a non-tidal version of the circulation model. It is demonstrated that assimilation of surface velocity data significantly improves the surface and subsurface correlation of model currents with moored current obseervations. These results from the AOSN-II period illustrate that surface-current assimilation is beneficial even in cases for which very high-resolution (3 km) atmospheric forcing is utilized. The assimilation approach is also tested with the hourly, unfiltered, CODAR-type HF radar-derived surface currents within a model configuration that includes tidal forcing. It is shown, that assimilation of unfiltered (with tides) surface-current observations into the model with tides improves the sub-tidal model prediction to the level comparable with the assimilation of filtered data into the non-tidal model, which is significant with respect to options for designing real-time nowcast and forecast systems. Finally, the approach is extended and evaluated for the direct assimilation of HF radar-derived radial velocity components. The model runs that included assimilation of radials from at least two HF radar sites show better correlation with observations that the non-assimilative run, especially those runs that included radials from the Santa Cruz site. Directions of radials for that site coincide with the directions of dominant southward flow during upwelling events and the northward flow during relaxation events. Direct assimilation of radial currents extends the range of influence of the data into regions covered by only one HF radar site.
Showing items related by title, author, creator and subject.
Tokmakian, Robin Telrud (Monterey, California. Naval Postgraduate School, 1997-06);Two assimilation experiments have been conducted using the Semtner/Chervin Parallel Ocean Climate Model at 1/40 resolution to investigate the dynamical changes which occur with the application of the nudging method to ...
Haeger, Steven D.; Szczechowski, Carl; Carron, Michael; Chu, Peter C.; Wells, Susan K. (1997-03);This paper presents an analysis on the space/time statistical thermal structure in the Yellow Sea from the Navy's Master Observation Oceanography Data Set during 1929-1991. This analysis is for the establishment of an ...
Wind speed and moisture sensitivity tests of the NRL limited area dynamical weather prediction model : an OSSE study of ERICA IOP-4 Schulz, William J. (Monterey, California. Naval Postgraduate School, 1992-03);An Observing System Simulation Experiment (OSSE) is conducted to investigate the sensitivity of the Naval Research Laboratory (NRL) mesoscale model to atmospheric water and surface wind speed input. The explosively ...