In various scientific contexts, a scale height is a distance over which a quantity decreases by a factor of e (approximately 2.71828, the base of natural logarithms). It is usually denoted by the capital letter H.
Scale height used in a simple atmospheric pressure model
For planetary atmospheres, scale height is the increase in altitude for which the atmospheric pressure decreases by a factor of e. The scale height remains constant for a particular temperature. It can be calculated by the formula shown here.
Approximate scale heights for selected Solar System bodies follow.
Venus: 15.9 km
Earth: 8.5 km
Mars: 11.1 km
Jupiter: 27 km
Saturn: 59.5 km
Titan: 40 km
Uranus: 27.7 km
Neptune: 19.1–20.3 km
|H||scale height (m)|
|R||specific gas constant (J*kg-1*K-1)|
|T||mean atmospheric temperature in kelvins (250 K for Earth) (K)|
|g||acceleration due to gravity on planetary surface (m/s2)|