Rate at which unsaturated air cools as it travels vertically, provided that all temperature change is adiabatic (without heat exchange), and no condensation occurs. In dry air it can be approximated as 1 degree Celsius per 100 meters of rise. It can be used as a basis of comparison for actual temperature profiles of air and can help predict smoke stack gas dispersion characteristics. [Journal of Atmospheric Sciences; v51; 1237-1243; 1994.] [ Journal of Applied Meteorology; v33; 65-73; 1994.]
