# Toussaint's formula

From Glossary of Meteorology

## Toussaint's formula

A rule proposed by Toussaint for the linear decrease of temperature with height in an atmosphere for which the temperature at mean sea level is 15°C.

It is given by where

*t*is the temperature in degrees Celsius and*z*is the geometric height in meters above mean sea level. Toussaint's formula is used to determine temperature below 11 000 m in the ICAO Standard Atmosphere.

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