Nadia Ayoub (CNRS/LEGOS, France); Lucie Caubet (CNES/Université de Toulouse/LEGOS, France); Michel Tchilibou (CLS, France)

We investigate some of the challenging corrections applied to SWOT observations in shelf and coastal areas, using the Northeast Atlantic shelf as a benchmark region. In particular, we assess the accuracy of the DAC and tides corrections in this macro-tidal region, and we are questioning the quality of the L3 cross-track correction in a place where the SWOT swath cover continental or islands regions, with large uncertainties on the adjustment to other nadir observations. Both fast-sampling and Science orbits data are examined in our investigations. Empirical adjustment of the L3 cross-track correction will be assessed, using SWOT SHHA variance reduction as a quality metric, despite it is biased by the SSHA data dependency of the SWOT native correction, and comparisons with tide gauge observations. This is part of the SWOT ST project SCOEPUS (N. Ayoub and F. Lyard PIs)