Understanding the role of fine scales in enhancing biological activity in the highly dynamical Patagonian Continental Shelf.
The Patagonian Continental Shelf region is characterized by large tidal currents and by other strong signals as internal tides and internal gravity waves. These strong signals can generate an important bias in the satellite altimetry products as Sea Surface Height because of poor temporal and spatial sampling of satellite altimeters.
Accurate in-situ measurements are needed to discern what is observed with satellite altimetry and what should be removed from the signal retrieved. The SWOT 1-day repeat orbit was a unique opportunity for such a purpose.
Within the context of SABIO (Studying physical processes in the Southwestern Atlantic to understand BIOlogical productivity & regional ecosystems, CNES-EUMSTAT funded project), it was proposed to deploy four moorings during the first 90 days of the 1-day repeat orbit of SWOT pass number 7 in the Patagonian Continental Shelf (See figure). Two of the moorings consist of a bottom-frame equipped with instruments to measure Temperature, Conductivity and Pressure at the sea bottom and horizontal velocities in the whole water column. A fast-sampling rate (10 minutes) was set during the three months to ensure capturing detailed measurements of the physical processes that affect SSH.
The other two moorings were wire-walkers (https://rocklandscientific.com/products/moored-systems/wirewalker/) that were provided by Scripps Institution of Oceanography and consist of a CTD and a fluorometer attached to a vertical profiler fixed at the sea bottom.
In order to compare the satellite retrievals of the nadir with those of the swath, two moorings were deployed in the middle of one of the swaths and two others under the nadir track. Along-track and along-swath distance will be 40km. This configuration allowed detecting small-scale structures and compare SWOT nadir and swath spatial resolution ability of capturing sub-mesoscale structures.
The Patagonian Continental Shelf campaign helped understand the physical processes that contribute to enhancing the biological activity in the Argentine Continental Shelf.
Principal investigators: M. Saraceno (saraceno@cima.fcen.uba.ar), C. Guinet, LA Ruiz Etcheverry, A. Lucas
Institutions involved in the campaign: Instituto Franco-Argentino para el Estudio del Clima y sus Impactos (IRL IFAECI/CNRS-IRD-CONICET-UBA), INIDEP (Argentina), SCRIPPS (USA)
Contact point for the study site: Martin Saraceno (saraceno@cima.fcen.uba.ar)