FN Archimer Export Format
PT J
TI Surface signature of Mediterranean water eddies in the Northeastern Atlantic: effect of the upper ocean stratification
BT 
AF BASHMACHNIKOV, I.
   CARTON, Xavier
AS 1:1;2:2,3;
FF 1:;2:;
C1 Univ Lisbon OI FCUL, Fac Sci, Inst Oceanog, P-1749016 Lisbon, Portugal.
   Univ Bretagne Occidentale, UMR 6523, Lab Phys Oceans, F-29200 Brest, France.
C2 UNIV LISBON, PORTUGAL
   UBO, FRANCE
   IFREMER, FRANCE
SI BREST
SE PDG-ODE-LPO
IF 2.16
TC 20
TU Centre national de la recherche scientifique
   Institut de recherche pour le développement
   Institut français de recherche pour l'exploitation de la mer
   Université de Bretagne Occidentale
UR https://archimer.ifremer.fr/doc/00133/24424/22437.pdf
LA English
DT Article
CR SEMANE 2002
BO Thalassa
AB Meddies, intra-thermocline eddies of Mediterranean water, can often be detected at the sea surface as positive sea-level anomalies. Here we study the surface signature of several meddies tracked with RAFOS floats and AVISO altimetry. While pushing its way through the water column, a meddy raises isopycnals above. As a consequence of potential vorticity conservation, negative relative vorticity is generated in the upper layer. During the initial period of meddy acceleration after meddy formation or after a stagnation stage, a cyclonic signal is also generated at the sea-surface, but mostly the anticyclonic surface signal follows the meddy. Based on geostrophy and potential vorticity balance, we present theoretical estimates of the intensity of the surface signature. It appears to be proportional to the meddy core radius and to the Coriolis parameter, and inversely proportional to the core depth and buoyancy frequency. This indicates that surface signature of a meddy may be strongly reduced by the upper ocean stratification. Using climatic distribution of the stratification intensity, we claim that the southernmost limit for detection in altimetry of small meddies (with radii on the order of 10-15 km) should lie in the subtropics (35-45 degrees N), while large meddies (with radii of 25-30 km) could be detected as far south as the northern tropics (25-35 degrees N). Those results agree with observations.
PY 2012
SO Ocean Science
SN 1812-0784
PU Copernicus Gesellschaft Mbh
VL 8
IS 6
UT 000312698600001
BP 931
EP 943
DI 10.5194/os-8-931-2012
ID 24424
ER

EF