Illustration of the mesoscale dynamics in
the Mediterranean with thermal NOAA/AVHRR images from SATMOS/MétéoFrance and DLR
(but g: ocean colour/chlorophyll content from SeaWiFS, from ies).
Excepted image1a, images are single paths, and have been selected to illustrate either
general or peculiar circulation features. Temperature increases from blue to
red, but all images have an independent colour scale.
and/or between the coast and the southern edge of an AE creates small transient
e: the channel of Sardinia with an AE (blocked) at the entrance,
and the channel of Sicily (the upwelling cells along the southern coast of Sicily are typical
of summertime conditions).
f: The western Levantine subbasin, with libyo-egyptian (LE) eddies.
g: The Middle-East, with coastal instabilities revealed by their chlorophyll content.
h: The Northern Current off Turkey, showing sharp meanders and an eddy pinching off.
i: The Northern Current feeding the wind-induced Ierapetra eddy, east of Crete.
j: The Ligurian subbasin, with a vortex dipole (mushroom-like structure) north of Corsica;
the cold patch east of the strait of Bonifacio reveals the divergence induced by a strong (past)
mistral wind event.
k: the Liguro-Provençal subbasin: in its eastern part the Northern Current flows close
to the coast since the slope is steep; off the gulf of Lions it skirts the wide continental shelf along the
~200m isobath, and thus crosses the gulf offshore; south (and probably east of
the strait of Bonifacio too) the cold area reveals where wintertime deep
convection occurs, forming dense mediterranean water (image typical of
l: Upwelling cells in the gulf of Lions induced by a strong Mistral event (image typical of
- a: monthly composite of January 1998, showing the general path of AW (warmer)
describing a counterclockwise gyre in both western and eastern basins.
- b: Alboran filled by two gyres, its classic situation.
- c: the jet of AW on the western half of the eastern Alboran gyre reaches the algerian slope
near 0° and continues as the Algerian Current, which can be seen (colder signature) propagating
alongslope as far as ~4°E (south of Minorca), where it veers offshore (due to
eddies interactions, not shown). An algerian eddy (AE) can be seen south of Ibiza.
- d: AEs interacting in the eastern part of the Algerian subbasin.
Upwelling cells (dark blue tongues) are generated on the southwestern side of the AEs,
where the current is directed offshoreward. The strong shear between 2
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