18 Eddies in the Red Sea as seen by Satellite SAR Imagery
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Fig. 18.10 a Spatial
distribution of anti-cyclonic
basin-scale eddies detected in
2006–2011. Solid circles
mark “black” eddies, open
circles mark “white” eddies.
The diameters of the circles
correspond to those of the
eddies. b Spatial distribution
of cyclonic basin-scale eddies
detected in 2006–2011. Solid
circles mark “black” eddies,
open circles mark “white”
eddies. The diameters of the
circles correspond to those of
the eddies
On May 19 and 24, 2009, two Envisat ASAR WS images were acquired over the
same part of the Red Sea, and they show manifestations of basin-scale “black” and
“white” eddies, respectively. A closer look at the observed signatures reveals that
apparently the same eddy was imaged twice, but visualized in two different ways, i.e.
as “black” eddy (May 19, Fig. 18.11a) and as “white” eddy (May 24, Fig. 18.11b).
The time in between the two SAR acquisitions is 5 days, but eddies with diameters of