Different sea surface heights used in altimetry

Overview of the different fields used in altimetry (Crédits CLS)

 

The Altimeter measurement allows to retrieve the SSH, i.e. the height from the reference ellipsoid to the instantaneous sea surface.

A MSS can be used to compute the SLA, i.e. the height between the mean state of the SSH (over a specific period N, see the altimeter reference period page) and the instantaneous sea surface:

SLAN = SSH – MSSN

A MDT field can be used to retrieve the ADT, i.e. the sea surface height above the Geoid:

ADT = SLAN + MDTN

The difference between the MSS and MDT is the Geoid:

MSSN = MDTN + Geoid