The rate of cooling of ascending saturated air. It is approximately 1.5°C/1000 ft but may reduce to as little as 1°C/1000 ft in the warm saturated tropical regions. It may exceed 2°C/1000 ft when the temperature of the air falls below the freezing point until it is no longer saturated and the lapse rate falls to that of dry air. The same as saturated adiabatic lapse rate and moist adiabatic lapse rate.
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