The International Organization for Standardization (ISO), more specifically ISO 19111, offers the following two definitions:[1] ISO 6709 (2008 version) makes the following additional definition: The International Civil Aviation Organization (ICAO) offers similar definitions:[2] ICAO further defines: I.e., elevation would be the altitude of the ground or a building.
Certain vertical coordinates are not based on length, for example, geopotential numbers have units of m2/s2.
[3][4] However, this practice is not acceptable with the International System of Units (SI).
It is used for distance climbed during sports such as mountaineering, skiing, hiking, running or cycling[6] In German-speaking countries the abbreviation 'Hm' for Höhenmeter ("height metre") is used; if it is preceded by a '±' it refers to the cumulative elevation gain.
Various instruments and techniques may be used for measuring or determining vertical position: Many physical phenomena are related to vertical position, as driven by gravity: When one gives the value of a quantity, any information concerning the quantity or its conditions of measurement must be presented in such a way as not to be associated with the unit.