Sea level
AVERAGE LEVEL FOR THE SURFACE OF ONE OR MORE OF EARTH'S OCEANS
Mean sea level; Sea Level; Sea-level; Sea levels; Eustasis; Mean sea-level; Eustatic change; Eustacy; Sealevel; Eustatic; Eustatic movements; Mean Sea Level; Höhe über dem Meeresspiegel; Mean level of the sea; Höhennormal; Glacio-eustatic; Median sea level; Sea-levels; Global mean sea level
Mean sea level (MSL, often shortened to sea level) is an average surface level of one or more among Earth's coastal bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical datuma standardised geodetic datumthat is used, for example, as a chart datum in cartography and marine navigation, or, in aviation, as the standard sea level at which atmospheric pressure is measured to calibrate altitude and, consequently, aircraft flight levels.