Acid rain is a form of precipitation that possess acidic components such as; Sulphuric or nitric acid that falls to the ground from the atmosphere in wet or dry forms. These includes; rain, fog, snow, hail or even dust. Acid rain being acidic means it has elevated levels of hydrogen ions (low pH). It can be harmful to plants, aquatic animals and infrastructures.
When gases emitted by motor vehicles and industrial processes reacts with clouds, the water vapour in the clouds combines with them forming acids which via precipitation are returned to earth as acid rain.
MEASURING ACID RAIN
Acidity and alkalinity are measured using a pH scale for which 7.0 is neutral. The degree of acidity and alkalinity of a substance defines it's pH level. The lower a substance's pH, the more acidic it is and the higher the pH, the more alkaline or basic it is. Normal rain has a pH of about 5.6. Acid rain usually has a pH between 4.2 and 4.4
WHAT CAUSES ACID RAIN?
Acid rain results when Sulphur Dioxide (SO2) and oxides of Nitrogen (NOx) are emitted into the atmosphere and conveyed by wind and air currents . The Oxides of both Sulphur and Nitrogen react with water, oxygen and other chemicals to form sulphuric and nitric acids respectively. These then mix with water and other materials before falling to the ground as precipitation infused with acidic components.
While some portion of the oxides of Sulphur and Nitrogen that causes acid rain is from natural sources such as; volcanoes, most of it comes from the burning of fossil fuels.
EFFECTS OF ACID RAIN
- Effect on Aquatic Environment: Acid rain either falls on aquatic life directly or gets run off through the forests, roads and fields to flow into streams, rivers and lakes. Over a period of time, acids gets accumulated in the water and lower the overall pH level of the water body.
Aquatic plants and animals needs a particular pH of about 4.8 to survive beyond this, it becomes toxic to them.
Species of fishes, plants and insects in some lakes and water bodies have been reduced or gone on extinction due to acid rain.
- Effect on Forests: It makes trees vulnerable to disease, extreme weather, and insects by destroying their leaves, damaging the bark and arresting their growth.
Effect on Architecture and Buildings: Avid rain on buildings especially those constructed with limestone that possess aluminium roofs often react with minerals from acidic rain thus, corroding them away. Irreplaceable damage can be caused by acid rain.
Effect on Public Health: Oxides of Sulphur and Nitrogen and their particulate matter derivates can degrade visibility and cause accidents leading to injuries and death. Human health is not directly affected by acid rain because avid rain water is less concentrated to pose serious health problems.
However, dry depositions known as gaseous particulates in the air can cause serious health problems when inhaled. Excess levels of acidic components and deposition in dry form present in the air can cause severe problems in human organs such as; lungs and heart resulting in bronchitis and asthma.
SOLUTIONS TO CURBING ACID RAIN
Acid rain can be prevented or curbed if proactive measures are put in place to preventing it. These could be achieved in the following ways;
Watching Pollution
Recycling
Energy production without fossil fuel