@article{fdi:010068115,
  title = {{A}n index to distinguish surface- and subsurface-intensified vortices from surface observations},
  author = {{A}ssassi, {C}. and {M}orel, {Y}ves and {V}andermeirsch, {F}. and {C}haigneau, {A}lexis and {P}egliasco, {C}. and {M}orrow, {R}. and {C}olas, {F}ran{\c{c}}ois and {F}leury, {S}. and {C}arton, {X}. and {K}lein, {P}. and {C}ambra, {R}.},
  editor = {},
  language = {{ENG}},
  abstract = {{I}n this study, the authors first show that it is difficult to reconstruct the vertical structure of vortices using only surface observations. {I}n 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. {T}he 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. {W}hile 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. {T}he validity of the index is then analyzed using results from a realistic regional circulation model of the {P}eru-{C}hile upwelling system, where both surface and subsurface eddies coexist. {T}he 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. {H}owever, the errors reach 24%, and some possible improvements of the index calculations are discussed.},
  keywords = {},
  booktitle = {},
  journal = {{J}ournal of {P}hysical {O}ceanography},
  volume = {46},
  numero = {8},
  pages = {2529--2552},
  ISSN = {0022-3670},
  year = {2016},
  DOI = {10.1175/jpo-d-15-0122.1},
  URL = {https://www.documentation.ird.fr/hor/fdi:010068115},
}