How Acidic is Rain in New York State?
The average pH of rainfall in New York State ranges from 4.0 to 4.5, which is up to 30 times more acidic than “normal.” A pH scale is used to measure acidity, with 0 being the most acidic and 14 the most alkaline. A value of 7 is neutral. Solutions with a pH of less than 7 are acids, while those with a pH greater than 7 are bases. The scale also is logarithmic, meaning that a one-unit change actually represents a tenfold change. Rainfall is somewhat acidic by nature, primarily due to carbon dioxide and water vapor combining in the atmosphere. While the acidity of natural precipitation varies somewhat, it normally is around pH 5.6.
