acid precipitation

American  

noun

1. meteorological precipitation that is relatively acidic.

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acid precipitation Scientific  

1. 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.

2. Also called acid rain

3. See Note at acid deposition

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Etymology

Origin of acid precipitation

First recorded in 1975–80

Example Sentences

The acid precipitation around alkali and sulphuric acid works is well known; the acid character of rains collected near and in cities, and the remarkable ammoniacal strength of some local rainfalls, have been fully discussed.

From Project Gutenberg