Retrieving density and velocity fields of the ocean's interior from surface data

TitleRetrieving density and velocity fields of the ocean's interior from surface data
Publication TypeJournal Article
Year of Publication2014
AuthorsLiu L., Peng S.Q, Wang J.B, Huang R.X
JournalJournal of Geophysical Research-Oceans
Volume119
Pagination8512-8529
Date Published2014/12
Type of ArticleArticle
ISBN Number2169-9275
Accession NumberWOS:000348452800018
KeywordsData assimilation; energy; enso; global ocean; hybrid coupled model; HYCOM; isQG method; NCODA reanalysis; Potential vorticity; prediction; quasi-geostrophic dynamics; reconstruction; satellite remote; sea; sea surface and interior; sensing; SODA reanalysis; turbulence
Abstract

Using the interior+surface quasigeostrophic (isQG) method, the density and horizontal velocity fields of the ocean's interior can be retrieved from surface data. This method was applied to the Simple Ocean Data Assimilation (SODA) and the Hybrid Coordinate Ocean Model (HYCOM)/Navy Coupled Ocean Data Assimilation (NCODA) reanalysis data sets. The input surface data include sea surface height (SSH), sea surface temperature (SST), sea surface salinity (SSS), and a region-averaged stratification. The retrieved subsurface fields are compared with reanalysis data for three tested regions, and the results indicate that the isQG method is robust. The isQG method is particularly successful in the energetic regions like the Gulf Stream region with weak stratification, and the Kuroshio region with strong correlation between sea surface density (SSD) and SSH. It also works, though less satisfactorily, in the Agulhas leakage region. The performance of the isQG method in retrieving subsurface fields varies with season, and peaks in winter when the mixed layer is deeper and stratification is weaker. In addition, higher-resolution data may facilitate the isQG method to achieve a more successful reconstruction for the velocity retrieval. Our results suggested that the isQG method can be used to reconstruct the ocean interior from the satellite-derived SSH, SST, and SSS data in the near future.

DOI10.1002/2014jc010221
Short TitleJ Geophys Res-Oceans
Student Publication: 
No