The Tunguska catastrophe in 1908 evidently led to high levels of acid rain. This is the conclusion reached by Russian, Italian and German researchers based on the results of analyses of peat profiles taken from the disaster region. In peat samples corresponded to 1908 permafrost boundary they found significantly higher levels of the heavy nitrogen and carbon isotopes 15N and 13C.

Prior to the federal Clean Air Act, unhindered industrial emissions were released into the air throughout the Midwestern and Eastern United States for decades. Many of those harmful chemicals came right back down to earth in the form of acid rain, a chemical concoction that includes nitric and sulfuric acid.

Acid rain was one of the world’s worst pollution problems of the 1970s and 1980s, affecting large areas of upland Britain, as well as Europe and North America.

The release of sulfur and nitrogen into the atmosphere by power plants and agricultural activities plays a minor role in making the ocean more acidic on a global scale, but the impact is greatly amplified in the shallower waters of the coastal ocean, according to new research by atmospheric and marine chemists.

Nitric acid is a notoriously strong and chemically destructive compound found in water on earth and in our atmosphere. However, a team of researchers have found that its punch is much weaker when it sits on the top of a water surface.