meteorological precipitation that is relatively acidic.
Compare acid rain.
Origin of acid precipitation
First recorded in 1975–80
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Science definitions for acid precipitation
Any form of precipitation, including rain, snow, hail, fog, or dew, that is high in acid pollutants, especially sulfuric and nitric acid. Acid precipitation has a pH of less than 5.6 (the normal acidity of unpolluted atmospheric water) and is often less than pH 5.0. Also called acid rain See Note at acid deposition.
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