Assassi C. auteur aut IRD Morel Yves auteur aut IRD Vandermeirsch F. auteur aut IRD Chaigneau Alexis auteur aut IRD Pegliasco C. auteur aut IRD Morrow R. auteur aut IRD Colas François auteur aut IRD Fleury S. auteur aut IRD Carton X. auteur aut IRD Klein P. auteur aut IRD Cambra R. auteur aut IRD text journalArticle eng text/pdf born digital access In this study, the authors first show that it is difficult to reconstruct the vertical structure of vortices using only surface observations. In particular, they show that the recent surface quasigeostrophy (SQG) and interior and surface quasigeostrophy (ISQG) methods systematically lead to surface-intensified vortices, and those subsurface-intensified vortices are thus not correctly modeled. The authors then investigate the possibility of distinguishing between surface-and subsurface-intensified eddies from surface data only, using the sea surface height and the sea surface temperature available from satellite observations. A simple index, based on the ratio of the sea surface temperature anomaly and the sea level anomaly, is proposed. While the index is expected to give perfect results for isolated vortices, the authors show that in a complex environment, errors can be expected, in particular when strong currents exist in the vicinity of the vortex. The validity of the index is then analyzed using results from a realistic regional circulation model of the Peru-Chile upwelling system, where both surface and subsurface eddies coexist. The authors find that errors are mostly associated with double-core eddies (aligned surface and subsurface cores) and that the index can be useful to determine the nature of mesoscale eddies (surface or subsurface intensified) from surface (satellite) observations. However, the errors reach 24%, and some possible improvements of the index calculations are discussed. specialized 032 020 46 8 2529-2552 2016 0022-3670 https://www.documentation.ird.fr/hor/fdi:010068115 10.1175/jpo-d-15-0122.1 0022-3670 [F B010068115] https://www.documentation.ird.fr/hor/fdi:010068115 https://www.documentation.ird.fr/intranet/publi/2016/10/010068115.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2016-11-03 2017-08-23 fdi:010068115 fre