Английская Википедия:Height above mean sea level

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Шаблон:Redirect Шаблон:Short description Height above mean sea level is a measure of a location's vertical distance (height, elevation or altitude) in reference to a vertical datum based on a historic mean sea level. In geodesy, it is formalized as orthometric height. The zero level varies in different countries due to different reference points and historic measurement periods. Climate change and other forces can cause sea levels and elevations to vary over time.[1]

Uses

Elevation or altitude above sea level is a standard measurement for:

Units and abbreviations

Elevation or altitude is generally expressed as "metres above mean sea level" in the metric system, or "feet above mean sea level" in United States customary and imperial units. Common abbreviations in English are:

  • AMSL – above mean sea level[3]
  • FAMSL – feet above mean sea level[4]
  • FASL – feet above sea level[5]
  • MAMSL – metres above mean sea level[4]
  • MASL – metres above sea level[4][5]
  • MSL – mean sea level[6]

For elevations or altitudes, often just the abbreviation MSL is used, e.g., Mount Everest (8849 m MSL), or the reference to sea level is omitted completely, e.g., Mount Everest (8849 m).[6]

Methods of measurement

Шаблон:Refimprove section Elevation or altitude above sea level is most commonly measured by:

Accurate measurement of historical mean sea levels is complex. Land mass subsidence (as occurs naturally in some regions) can give the appearance of rising sea levels. Conversely, markings on land masses that are uplifted (due to geological processes) can suggest a relative lowering of mean sea level.

See also

References

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