Three procedures for the analysis of the geostrophic circulation associated with an eddy over the Catalan Continental Shelf
Abstract
The ET2001 ('Eddy Tracking') oceanographic cruise took place in September 2001 in the Catalan continental shelf. This cruise was planned to monitor a mesoscale eddy combining ADCP data with simultaneous hydrological surveys (carried out through CTD casts and repeated Nv-Shuttle fast surveys). The resulting data set showed a well developed anticyclonic eddy reaching a depth of at least 100 m over the continental shelf. Three methods have been used to recover the hydrographic and velocity fields. In the first, dynamic topography is computed from hydrographic data relative to the deepest layer, and the resulting geostrophic velocity field is afterwards corrected using the ADCP measurements. The barotropic component of the motion field is determined by assuming that actual velocities are non-divergent at the reference level taken to compute dynamic height. A sensitivity analysis of results with respect to the reference level has been performed. The second method is a generalization of the first, and bases on the minimization of the differences between geostrophic and ADCP velocities along the whole water column. Finally, a multivariate analysis method mixing ADCP and hydrographic data when carrying out the spatial interpolation of the fields has also been tested.
- Publication:
-
EGS - AGU - EUG Joint Assembly
- Pub Date:
- April 2003
- Bibcode:
- 2003EAEJA....12187R