environmental lapse rate
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environmental lapse rate[in¦vī·ərn¦mənt·əl ′laps ‚rāt]
The rate of decrease of temperature with elevation in the atmosphere. Also known as atmospheric lapse rate.
environmental lapse rate (ELR)
The lapse rate in the surrounding air within which a volume of air is being lifted. The average rate is 2°C/1,000 ft. This should not be confused with dry adiabatic lapse rate (DALR) and saturated adiabatic lapse rate (SALR), in which the lapse rates are fixed. See also dry adiabatic lapse rate and saturated adiabatic lapse rate.