Parameter Tree:
EARTH SCIENCE > OCEANS > SEA SURFACE TOPOGRAPHY

Definition:
To measure sea surface height, or surface topography, scientists need
to obtain the precise distance between the satellite and the center of
the Earth and the precise distance between the satellite and the sea
surface. Sea surface height is then calculated by subtracting the
distance between the sea surface and the satellite from the distance
between the center of the Earth and the satellite. The distance between
the satellite and the center of the Earth is obtained by carefully
monitoring the satellite position at all times.


Reference:
http://www.icess.ucsb.edu/geos/11151.html