Environmental Disasters: Causes and Effect of Acid Rain

Introduction

Many human activities, including the burning of fossil fuels, cause pollution. Pollution is the release of harmful substances called pollutants into the environment. The air pollution created when fossil fuels burn does not stay in the air forever. Instead, it can travel great distances, and fall to the ground again as dust or rain. When airborne chemicals and pollutants fall to the Earth or deposit, it is called deposition.

Acid rain forms when clean rain comes into contact with pollutants in the air, like sulfur dioxide (SO2), carbon dioxide (CO2), and nitrogen oxides (NOx). Although sulphur dioxide and carbon dioxide occur in the air naturally, burning fossil fuels adds more of these chemicals to the air. When these pollutants are released into the air, they mix and react with water, oxygen, and other chemicals to form acid rain. Acid rain then falls to the Earth where it can damage plants, animals, soil, water, and building materials.

What Is Acid Rain?

Acid rain can be defined or known as any form of precipitation that is unusually acidic, meaning that it has elevated levels of hydrogen ions. It can have harmful effects on plants, aquatic animals and infrastructure.

Air Pollution Causes Acid Rain. Scientists have discovered that air pollution from the burning of fossil fuels is the major cause of acid rain. Power plants and factories burn coal, oil, and natural gas to produce the electricity we need to do all kinds of things, like a light our homes and power our factories. Cars, trucks, and aeroplanes also run on gasoline, a fossil fuel which sends smoke and fumes into the atmosphere. In the air, these pollutants combine with moisture to form acid rain.

The main chemicals in air pollution that create acid rain are sulphur dioxide (SO2) and nitrogen oxides (NOx). Acid rain usually forms high in the clouds where SO2 and NOx react with water and oxygen. This forms sulfuric acid and nitric acid in the atmosphere. Sunlight increases the speed of these reactions, and therefore the amount of acid in the atmosphere. Rainwater, snow, fog, and other forms of precipitation then mix with the sulfuric and nitric acids in the air and fall to Earth as acid rain.

Effect of Acid Rain

Forests

Acid rain causes significant damage to forests. It directly affects trees and other plants which are important to the ecosystem as a whole because they are primary producers. Primary producers are organisms that produce their own food through photosynthesis, a series of chemical reactions that convert water into sugar using light from the sun to provide energy. Plants and some microscopic animals have this ability. Plants are important to ecosystems because they feed everything else and provide important habitat for other animals. If trees and plants are damaged by acid rain, the effects are felt throughout the entire ecosystem.

Acid rain causes trees in forests to grow more slowly, and in some sensitive species, it can even make the leaves or needles turn brown and fall off. Red Spruce and Sugar Maple, two species of trees found mainly in the East and in New England, are very susceptible to acid rain damage. Acid rain damages trees by dissolving the calcium in the soil and in the leaves of trees. This hurts the tree because calcium is a mineral that trees need to grow. Once the calcium is dissolved, the rain washes it away so the trees and other plants cannot use it to grow. Acid rain washes other minerals and nutrients from the soil in a similar fashion, causing Nutrient Deficiency. This is why acid rain can cause trees to grow more slowly. Nutrient deficiency causes other problems for trees and plants.

The lack of nutrients weakens the trees and makes them more sensitive to the cold. A well-nourished tree in healthy soil will survive even a very cold winter with little difficulty, but a tree already weakened by a mineral deficiency can die during a cold winter. The weakened trees and plants are also more sensitive to insects and disease. At the same time, acid rain causes the release of substances such as aluminium from the soil. Aluminium can be very harmful to trees and plants. Once released into the soil, aluminium can end up in streams, rivers, and lakes, where it can harm or even kill fish. Less aluminium is released when the rainfall is cleaner.

The pollution that causes acid rain also causes haze by scattering light back towards the sky. Haze reduces the amount of light available for plants to use in photosynthesis. Since photosynthesis is the base of the food chain, acid rain can cause problems with the movement of nutrients to other organisms in ecosystems that are already impacted. Further reducing the amount of photosynthesis are acid fogs. Fog can often be more acidic than rainfall. When leaves are frequently bathed in acid fog, their protective waxy coating can wear away.

The loss of this coating damages the leaves and creates brown spots. The leaves are then unable to use photosynthesis to turn the energy in sunlight into food for growth. When leaves are damaged, they cannot produce enough food energy for the tree to remain healthy.

Ponds, Lakes, And Streams

The effects of acid rain are most clearly seen in aquatic environments such as streams, lakes, and marshes. Acid rain flows to streams, lakes, and marshes after falling on forests, fields, buildings, and roads. Acid rain also falls directly on aquatic habitats. Most lakes and streams have a pH between 6 and 8, because the buffering capacity of soil usually neutralizes slightly acidic, clean rain. Lakes and streams become acidic (pH value goes down) when the rainwater itself is so acidic that the surrounding soil cannot buffer the rain enough to neutralize it.

For this reason, some lakes in areas where the soil does not have a lot of buffering capacity are naturally acidic even without acid rain. In areas like the northeastern United States where soil buffering is poor, acid rain has made already slightly acidic lakes very acidic, with some lakes having a pH value of less than 5.

As lakes and streams become more acidic, the numbers and types of fish and other aquatic plants and animals that live in these waters decrease. Some types of plants and animals are able to tolerate acidic waters. Others, however, are acid-sensitive and will leave or die as the pH declines. Some acidic lakes have no fish because at pH 5 most fish eggs cannot hatch. At lower pH levels, adult fish can die. Substances like aluminium that wash into the water from the soil can also harm and kill fish.

Effects Of Acid Rain-Causing Pollutants On Humans

Acid rain looks, feels and tastes just like clean rain. Walking in acid rain, or even swimming in an acid lake, is no more dangerous for humans than walking or swimming in clean water. However, breathing air that contains the pollutants that cause acid rain can damage human health. Sulphur dioxide (SO2), nitrogen oxides (NOx), particulate matter, and ozone all irritate or even damage our lungs. These effects are mostly seen in people whose lungs have already been weakened by respiratory illness, but even healthy people can sometimes have pain or difficulty breathing because of air pollution.

Ozone is a dangerous pollutant that is caused by air pollution, especially in the summer. Exposure to high levels of ozone has been linked to a number of health problems. Ozone can make respiratory illnesses, such as asthma, emphysema, and bronchitis worse. Ozone can also reduce the respiratory system’s ability to fight off bacterial infections. Even healthy people can have symptoms related to ozone exposure, including coughing, pain with deep breathing, chest tightness, and shortness of breath. Over time, ozone can cause permanent damage to the lungs or even death. Small particles called particulate matter are made up of the same pollutants that cause acid rain. Particulate matter also damages the lungs.

The tiny particles of dust that make up particulate matter can bypass the body’s natural defences and become lodged deep in the lungs, where it can cause irritation and damage the lungs. SO2 and NOx, the pollutants that cause acid rain, can also reduce visibility, limiting how far into the distance we can see. These pollutants form small particles in the atmosphere. These particles reduce visibility by scattering light. Reduced visibility is most noticeable in places like National Parks, where people go to see some of the nation’s most beautiful landscapes.

Effects Of Acid Rain On Man-Made Materials

Acid rain eats away at stone, metal, paint—almost any material exposed to the weather for a long period of time. Human-made materials gradually deteriorate even when exposed to unpolluted rain, but acid rain speeds up the process. Acid rain can rust metals and cause marble statues carved long ago to lose their features. This happens because marble is made of a compound called calcium carbonate, which can be dissolved by acids.

Calcium carbonate is also found in limestone. Many buildings and monuments are made of marble and limestone and are damaged by acid rain. Repairing acid rain damage to buildings and monuments can cost billions of dollars. Historical monuments and buildings, such as the Lincoln Memorial in Washington, D.C., can never be replaced.

What Is Being Done?

There are other sources of energy besides fossil fuels. These include hydroelectric power, wind power, nuclear power, solar power, and fuel cells. Hydroelectric dams use the power of water to turn rurbines and make electricity. Windmills work the same way but instead, use the wind to turn the turbines.

People have been using wind and water power for centuries. Nuclear power plants collect the energy released by splitting tiny atoms apart inside nuclear reactors. Although nuclear power plants generate dangerous waste that must be disposed of carefully, a small amount of nuclear fuel can make a very large amount of electricity. Some people also use solar power, or power from the sun, to make electricity. Some houses use solar power to heat water for showers, and even some traffic signs run off of solar panels. Fuel cells are similar to batteries, except that fuel cells run on oxygen and hydrogen. They use chemical reactions to generate electricity and produce water as waste. All sources of energy have benefits and limitations, including the cost of producing energy. All of these factors must be weighed when deciding which energy source to use.

Conclusion

The harm caused by natural and man-made disasters is not only environmental but it also has an effect on our human rights and health. Events such as acid rain can transpire through human error and carry grave consequences. However, with a little vigilance, they shouldn’t occur in the first place. Man-made disasters have an element of human intent, negligence or error involving a failure of a man-made system as opposed to natural disasters resulting from natural hazards.