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
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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