Definition: rain water with the chemical of sulfuric acid ( H2 SO 4) with around a pH level of 3 to 6. it is a term that describes higher then normal amounts of nitric and sulfuric acids.

As we know. Acid rain is a major component of air pollution and since pollution is a factor in Global Warming it is safe to say that Acid Rain is a component to Global Warming. Acid rain is found in the form of rain, snow, fog, dew and dry particles such as, gas and particles. About half of the acidity in the atmoshpere falls back to earth through dry deposition as gases and dry particles. The wind blows these acidic particles and gases onto buildings, cars, homes, and trees. In some instances, these gases and particles can eat away the things on which they settle. The use of tall smokestacks to reduce local pollution has contributed to the spread of acid rain by releasing gases into regional atmospheric circulation. Often deposition occurs a considerable distance downwind of the emissions, with mountainous regions tending to receive the most (simply because of their higher rainfall)

Flow chart showing dry and wet deposition processes. If you have difficulty viewing this graphic, or need additional information, contact Cindy Walke, Web Manager, at 202-343-9194.
Flow chart showing dry and wet deposition processes. If you have difficulty viewing this graphic, or need additional information, contact Cindy Walke, Web Manager, at 202-343-9194.
The coal-fired Gavin power plant in Cheshire, Ohio
The coal-fired Gavin power plant in Cheshire, Ohio

  • natural sources contribute to a natural amount of acid rain including: volcanoes, decaying vegetation, man-made sources, and
  • From factories, cars emissions, sulfur dioxide (SO2) and nitrogen oxides (NOx) resulting from fossil fuel buring emitted into the air where it is mixed with the humidity within the atmosphere.
  • when the mild solution of sulfuric acid and nitric acid reacts in the air with oxygen, water and other chemicals, winds blow them across the atmosphere increasing the spread of acid rain
  • the sulfuric acid then falls towards the earth as it rains
  • WET DEPOSITION: acidic rain, fog, and snow. When the chemicals are blown into areas with wet weather, the acids can fall to the ground in the form of rain, snow, fog, or mist.
  • DRY DEPOSITION: In dry areas where acidic chemicals go into dust or smoke and fall to the ground through dry deposition, sticking to the ground, buildings, homes, cars, and trees

  • acidication of laks and streams
    • most lakes/rivers have pH between 6 and 8 but acid rain affect lakes that have a little ability to neutralize acidi compounds (buffering capacity) and thus become acidic
    • causes deaths and a decrease in biodiversity of fish as well as deformations
    • Acid rain causes acidification of lakes and streams and contributes to damage of trees at high elevations (for example, red spruce trees above 2,000 feet in elevation).
  • damages of trees
    • trees can just die off, as well as have a slower growth, injury tolerance and soil degradation so that future trees cannot grow
    • damages trees by damaging their leaes and limiting the nutrient available to them
  • accelerated the decay of building materials and paints including buildings, status, and sculputes
    • acid rain accelerates the decay of building materials and paints, including irreplaceable buildings, statues,and sculptures that are part of our nation's cultural heritage.
      • especially in cars, varnish and paint
  • decreases visbility
    • prevent full visibility in the air because of the chemicals in the air
    • 50-60% of the visibility reduction in the USA is due to sulfate particles
    • Sulfur dioxide emissions lead to the formation of sulfate particles in the atmosphere.
  • harmful to human health:
    • harmflu because it usually cannot be detected as it looks, smells and tastes like regular rain
    • deformations, cancer, lung inflammation, asthma, increased moralitiy rates, are just some of the health issues associated with acid rain
    • Decreases in nitrogen oxide emissions are also expected to have a beneficial impact on health effects by reducing the nitrate component of inhalable particulates and reducing the nitrogen oxides available to react with volatile organic compounds and form ozone.

  • cleaning up smokestakcs and exhaust pipes-->using alternative sources of energy instead of coal burning
    • adding limestone to lakes to "cancel out" the acidity within them, however this is very expensive and is considered only a short-term solution
    • individual awareness
      • use energy and electricity wisely
      • take care and use your vechicle as sparingly as possible
    • is monitored by the Clean Air Act that aims to reduce the levels of fine sulfate and nitrate partices
      • by 2010 tries to reduce the concentrations of SO2 and NO4
  • In the United States, many coal-burning power plants use Flue gas desulfurization (FGD) to remove sulphur-containing gases from their stack gases
  • A number of treaties have been signed by nations who are concerned about air pollution and coincidentally those who have a large amount of pollution. However there is still irony in the fact that some of the most polluted countries like India and China still refuse to aign certain agreements.
    • Some new treaties include Sulphur Emissions Reduction Protocol under the Convention on Long-Range Transboundary Air Pollution. ===Emissions trading===

  • not all the health effects of acid rain can be directly linked to just the acid rain
  • cannot link or account for what percent of human emissions of SO2 and NO4 causes the increase in acid rain ----
[[ BY: Kaylee Sager & James McCann | BY: Kaylee Sager & James McCann]]