Acid rain is one of the most dangerous and widespread forms of pollution. Sometimes called “the unseen plague,” acid rain can go undetected in an area for years. Technically, acid rain is rain that has a larger amount of acid in it than what is normal.
The acidity of rain in parts of Europe and North America has dramatically increased over the past few decades. It is now common in many places for rain to be ten to seventy times more acid than unpolluted rain. Many living and non-living systems become harmed and damaged as a result of acid rain.
Causes of Acid Rain:
Acid rain is caused by smoke and gases that are given off by factories and cars that run on fossil fuels. When these fuels are burned to produce energy, the sulfur that is present in the fuel combines with oxygen and becomes sulfur dioxide; some of the nitrogen in the air becomes nitrogen oxide. These pollutants go into the atmosphere, react with rain water and form acid and produce acid rain. The main reactions are as follows:
ADVERTISEMENTS:
2SO2 + O2 – 2SO3
2NO + O2 – 2NO2
SO3 + H2O – H2SO4
ADVERTISEMENTS:
NO2 + H2O – HNO2 + NHO3
The pH of natural rain water is near about 5.6 but the presence of H2SO4 and HNO3 lowers down its pH.
Effect on Environment:
Acid rain is an extremely destructive form of pollution, and the environment suffers from its effects. Forests, trees, lakes, animals and plants suffer from acid rain. Trees are extremely important natural resource. They provide timber, regulate local climate, and forests are homes to wildlife.
Acid rain can make trees lose their leaves or needles. The needles and leaves of the trees turn brown and fall off. Trees can also suffer from stunted growth; and have damaged bark and leaves, which makes them vulnerable to weather, disease, and insects. Lakes are also damaged by acid rain.
Effect on Architecture:
ADVERTISEMENTS:
Architecture and artwork can be destroyed by acid rain. Acid particles can land on buildings, causing corrosion. When sulfur pollutants fall of the surfaces of buildings (especially those made out of sandstone or limestone), they react with the minerals in the stone to form a powdery substance that can be washed away by rain.
This powdery substance is called gypsum. Acid rain can damage buildings, stained glass, railroad lines, airplanes, cars, steel bridges, and underground pipes.
Effect on Human:
Humans can become seriously ill, and can even die from the effects of acid rain. One of the major problems that acid rain can cause in a human being is respiratory problems. Many can find it difficult to breathe, especially people who have asthma. Asthma, alongwith dry cough, headaches and throat irritations can be caused by the sulfur dioxides and nitrogen oxides from acid rain.
Acid rain can be absorbed by both plants (through soil and/or direct contact) and animals (from things they eat and/or direct contact). When humans eat these plants or animals, the toxins inside of their meals can affect them. Brain damage, kidney problems, and Alzheimer’s disease has been linked to people eating “toxic” animals/plants.