Altimeter product Means and Climatologies (multimission, level 4), Global

Ssalto/Duacs multimission gridded sea surface heights products in version DT2021. From January 1993 to the last extension of the Delayed-time products, the long delayed-time dataset allows to compute statistical climatologies of Sea Level Anomalies maps (MSLA) over different periods of time.

Computed with respect to a twenty-year mean profile [1993-2012], and including the seasonal variability (no annual cycle is removed).

Averaged MSLA and Climatological MSLA are created from daily Ssalto/Duacs - DT MSLA - Merged Product - best sampling available in time (i.e. "all-sat-merged" serie, see Global Ocean gridded L4 Sea Surface Heights and derived variables reprocessed (1993- ongoing) and NRT for further information).

The set of variables are the following : EKE (Eddy Kinetic Energy) MSLA-H (Sea Level Anomaly H, sea surface height above sea level) MSLA-U (Sea Level Anomaly U, surface geostrophic eastward sea water velocity assuming sea level for_geoid) MSLA-V (Sea Level Anomaly V, surface geostrophic northward sea water velocity assuming sea level for geoid) MADT-H (Absolute Dynamics Topography H : sea surface height above geoid) MADT-U (Absolute Dynamics Topography U, surface geostrophic eastward sea water velocity) MADT-V (Absolute Dynamics Topography V, surface geostrophic northward sea water velocity)

Three kinds of means are proposed:

• Monthly means MSLA are calculated by averaging the daily maps of delayed-time sea level anomalies over a same month from January 1993 up to August 2023. We obtain one data file and one map for each month for each year (368 files)
• Seasonal climatologies of MSLA are calculated by averaging the daily maps of delayed-time sea level anomalies averaging season by season. We obtain one file and one map per season (JFM - AMJ - JAS- OND) (4 files)
• Monthly climatologies MSLA are calculated by averaging the daily maps of delayed-time sea level anomalies over a same month from January 1993 up to December 2022. We obtain one data file and one map for each month (12 files)