3. Stability

Changing Stability » Heating and Cooling Stability from Surface Cooling

Pure nocturnal radiative cooling in calm air results in a shallow surface-based inversion. The depth of the inversion increases with greater duration of the cooling, while the strength of the inversion increases with the degree of cooling.

Wind complicates the effects of cooling of the ground on the low-level lapse rate. This is true for both radiative cooling and passage of air over colder ground. Turbulent mixing of the air cooled at the ground with warmer air above tends to establish a surface layer with an adiabatic lapse rate capped by a turbulence inversion. Intermediate conditions and combinations between the ground inversion and the turbulence inversion can occur, depending on the relative degrees of wind and cooling.

Evaporative cooling of precipitation can produce significant cooling in an unsaturated boundary layer, resulting in a more stable environment.