Geopotential height approximates the actual height of a pressure surface above mean sea-level. Therefore, a geopotential height observation represents the height of the pressure surface on which the observation was taken. ... That means, at every point along a given contour, the values of geopotential height are the same.

How is geopotential height calculated?

Geopotential is defined by units of m**2/s**2 both on pressure levels and on the surface (orography). The geopotential height is the geopotential divided by the WMO-defined gravity constant of 9.80665 m/s**2, which is constant for all latitudes and all heights.

What is the difference between geopotential height and geometric height?

Geopotential height or geopotential altitude is a vertical coordinate referenced to Earth's mean sea level, an adjustment to geometric height (altitude above mean sea level) that accounts for the variation of gravity with latitude and altitude. Thus, it can be considered a "gravity-adjusted height".