less than 1 minute read

Acid Rain

Spatial Patterns Of Acidic Precipitation

Large regions are affected by acidic precipitation in North America, Europe, and elsewhere. A relatively small region of eastern North America is known to have experienced acidic precipitation before 1955, but this has since expanded so that most of the eastern United States and southeastern Canada is now affected.

Interestingly, the acidity of precipitation is not usually greater close to large point-sources of emission of important gaseous precursors of acidity, such as smelters or power plants that emit SO2 and NOx. This observation emphasizes the fact that acid rain is a regional phenomenon, and not a local one. For instance, the acidity of precipitation is not appreciably influenced by distance from the world's largest point-source of SO2 emissions, a smelter in Sudbury, Ontario. Furthermore, when that smelter was temporarily shut down by a labor dispute, the precipitation averaged pH 4.49, not significantly different from the pH 4.52 when there were large emissions of SO2.

Additional topics

Science EncyclopediaScience & Philosophy: 1,2-dibromoethane to AdrenergicAcid Rain - Atmospheric Deposition, Chemistry Of Precipitation, Spatial Patterns Of Acidic Precipitation, Dry Deposition Of Acidifying Substances