lapse rate


noun Meteorology.

the rate of decrease of atmospheric temperature with increase of elevation vertically above a given location.

Origin of lapse rate

First recorded in 1915–20

British Dictionary definitions for lapse rate

lapse rate

noun

the rate of change of any meteorological factor with altitude, esp atmospheric temperature, which usually decreases at a rate of 0.6°C per 100 metres (environmental lapse rate). Unsaturated air loses about 1°C per 100 m (dry adiabatic lapse rate), whereas saturated air loses an average 0.5°C per 100 m (saturated adiabatic lapse rate)

Scientific definitions for lapse rate

lapse rate
[ lăps ]

The rate of change of any meteorological phenomenon, especially atmospheric temperature with altitude. The lapse rate varies depending on the ground temperature, time of year (for example, in the Northern hemisphere it is lower in the winter), whether the air is over land or ocean water, and what the degree of moisture is.♦ The dry adiabatic lapse rate is the lapse rate of a dry mass of air which expands and cools as it rises. This rate is typically -9.8°C (-14.36°F) per 1,000 m (3,280 ft).♦ The saturated adiabatic lapse rate is the lapse rate of a wet mass of air, which slows down once the dew point has been reached and condensation has started to form. This rate ranges from 4°C (39.2°F) per 1,000 m (3,280 ft) to 9°C (48.2°F) per 1,000 m (3,280 ft).