Kolodziejczyk N., Reverdin G., Gaillard F., Lazar Alban. (2014). Low-frequency thermohaline variability in the Subtropical South Atlantic pycnocline during 2002-2013. Geophysical Research Letters, 41 (18), p. 6468-6475. ISSN 0094-8276.
Titre du document
Low-frequency thermohaline variability in the Subtropical South Atlantic pycnocline during 2002-2013
Kolodziejczyk N., Reverdin G., Gaillard F., Lazar Alban
Source
Geophysical Research Letters, 2014,
41 (18), p. 6468-6475 ISSN 0094-8276
Low-frequency variability of spiciness is observed in the Subtropical South Atlantic over the period 2002-2013 with the Argo gridded product In Situ Analysis System. Within the pycnocline, spiciness anomalies propagate at a mean speed of 0.04 +/- 0.02 m s(-1), the same speed as the gyre mean circulation, from the Agulhas Retroflection region off South Africa (similar to 35 degrees S-20 degrees E) toward the South American coast (similar to 18 degrees S-35 degrees W). After 2010, propagation is still found, but stationary local spiciness generation is also found over the Subtropical South Atlantic. This spiciness increase is associated with high values of vertical Turner angle below the mixed layer base during late winter. This suggests spice injection resulting from penetrative convective mixing due to air-sea buoyancy loss. These features may have an impact on the low-frequency warm and salty signal produced by the Agulhas leakage in Subtropical South Atlantic and the upper branch of the Atlantic Meridional Overturning Circulation.
