# Homogeneous atmosphere

From AMS Glossary

## homogeneous atmosphere

- A hypothetical atmosphere in which the density is constant with height.

The lapse rate of temperature in such an atmosphere is known as the autoconvective lapse rate and is equal to*g*/*R*(or approximately 3.4°C/100 m), where*g*is the acceleration of gravity and*R*is the gas constant for air. A homogeneous atmosphere has a finite total thickness that is given by*R*_{d}*T*_{v}/*g*, where*R*_{d}is the gas constant for dry air and*T*_{v}is the virtual temperature (K) at the surface. For a surface temperature of 273 K, the vertical extent of the homogeneous atmosphere is approximately 8000 m. At the top of such an atmosphere both the pressure and absolute temperature vanish.