Acid rain is rainfall or moisture present in the atmosphere that has mixed with elements and gases. This causes the moisture to become more acidic than normal. This is measured with a scale called pH. While pure water has a pH of 7, rainfall is slightly acid at around 5.6. Acid rain measures in the 5.0-5.5 range.
Acid rain may be caused by natural or man-made means. Volcanoes or decaying vegetation are examples of natural causes, while emissions or industries such as electrical production plants may be man-made causes of acid rain. Factories, power stations, and even our own homes produce gases such as sulfur and nitrogen, when fossil fuels like coal and oil are burned. When these acid gases permeate the air, they mix with the clouds, causing acid rain.
The effects of acid rain can be felt on both our environment and on our personal health. Effects experienced in the environment include those on trees, plants, lakes and water life, and our buildings and monuments. Acid rain strips the minerals from the soil, leaving trees and plants lacking those important elements, and in some cases weakening them irretrievably. Water life have a difficult time adapting to and reproducing in lakes and waterways that are affected by acid rain, which may endanger those species in the area affected by acid rain. Many of our historical buildings and monuments are also negatively affected by acid rain, as the acid speeds up the erosion of stone and metal. Our personal health is at risk when we breathe in air pollution or drink water that has been contaminated by acid rain.
The Acid Rain Program in Title IV of the 1990 Clean Air Act Amendment created by Congress has helped to make reductions in emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx), by placing restrictions on fossil fuel-fired power plants. The efforts of the U.S. Environmental Protection Agency are a large way to help reduce acid rain, but as individuals, there are steps we can take to help in that reduction. Conserving energy in our homes by using energy-efficient appliances, turning off electrical devices when they are not in use, carpooling or walking, purchasing vehicles with low emissions, and remaining well-informed are ways that we, as individuals, can aid in the effort to reduce the causes of acid rain.