Acid Rain

 

Rainfall made sufficiently acidic by atmospheric pollution that it causes environmental harm, typically to forests and lakes. The main cause is the industrial burning of coal and other fossil fuels, the waste gases from which contain sulfur and nitrogen oxides, which combine with atmospheric water to form acids

Acid rain, also known as acid deposition, is caused by emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) from power plants, cars and factories. Natural sources like volcanoes, forest fires and lightning strikes also add to the man-made pollution. SO2 and NOx become acids when they enter the atmosphere and react with water vapor. The resulting sulfuric and nitric acids can fall as wet or dry depositions. Wet deposition is precipitation: acid rain, snow, sleet or fog. Dry deposition falls as acidic particulates or gases.