G-Shock GW-9200BPJ-1 - Manual (Page 86)

E-84
There are two standard methods of expressing altitude: Absolute altitude and
relative altitude. Absolute altitude expresses an absolute height above sea
level. Relative altitude expresses the difference between the height of two
different places.
Height of building 130 m
(relative altitude) Rooftop at an altitude of
230 m above sea level
(absolute altitude)
Sea Level