Acid rain is defined as rainfall or other forms of precipitation such as snow, fog, etc. It is exceptionally acidic, suggesting it contains high amounts of hydrogen ions and a low pH value. 

Acid rain comprises acidic water molecules that form due to air pollution, particularly the overwhelming sulfur and nitrogen produced by cars and production plants. 

Because this idea encompasses a wide range of acidic precipitation, it is commonly referred to as acid rain.

Acid rain has somehow grown more prevalent due to population growth and economic expansion. 

By discharging pollutants into global air movement channels, high exhaust pipes to alleviate localized emissions have led to the development of acid rain far and wide across the planet.

The dumping and accumulation frequently occur at a long-distance downstream of pollutants, with highland locations receiving the most deposition because of their higher downpour tendencies. 

How is acid rain formed?

Sulfur dioxide and nitrogen oxides released within the environment undergo a chemical conversion producing an acidic downpour. 

These chemical compounds formed in due process can ascend to great heights in the sky. At greater heights, they combine and react with water, oxygen, and other molecules to produce highly acidic contaminants, characterized as acid rain. 

Sulfur dioxide and nitrogen oxides are very easily soluble in water and can be dispersed long by the airflow. 

Henceforth, the chemical complexes can commute vast distances and fall as a part of the precipitation, hailstorm, snowfall, and mists that we encounter almost every time it rains.

What causes acid rain?

The primary causes of acid rain | Diagram Credit: Earth Eclipse

Acid rain is primarily a result of human activities that release nitrogen and sulfur oxides into the environment by fossil-fuel power stations, cars, and petroleum refineries. 

Electric power plants are accountable for roughly two-thirds of sulfur dioxide and one-fourth of nitrogen oxide in the environment. 

While artificial contaminants primarily cause most acidic rainfall, natural calamities can still play a role. 

Volcanoes eruptions, for instance, can generate acid rain by releasing pollutants into the atmosphere. 

These contaminants can be transported around the globe via air currents and converted to acid rain miles away from the source.

Effects of Acid Rain

Woodlands and wildlife are disappearing all across the planet. There are numerous empty water pools in Scandinavia that are stunningly clean but devoid of live organisms or green vegetation. 

Most of the freshwater fish species in the United Kingdom are endangered, and there have been instances of malformed fish hatching. Acid rain has significant negative implications for all aspects of the ecosystem.

1. Forest and Vegetations

Acid rain is known to trigger plants to develop slowly or perhaps even perish, but that is not all there is! 

Acid rain appears to have a more significant impact in specific locations than in other regions of the planet. 

When acid rain pours down on a forest, it seeps through the foliage and into the ground underneath. This impure water ultimately gets into creeks, tributaries, and water bodies.

And some soils have a “buffering capability,” which means they potentially neutralize the acidic compounds. 

Other grounds, however, are mildly acidic naturally, making them more vulnerable to the impacts of acid deposition. Acid rain can harm forests in a variety of ways, including:

  • Dilutes and flushes away the micronutrients from the topsoil that assist the healthy growth of trees.
  • Promote the discharge of dangerous compounds into the soil, like aluminum.
  • Washes off the glossy protective cover of foliage, causing them to be damaged and prohibiting efficient photosynthesis.

A confluence of such impacts undermines the development and lifespan of trees, making them more vulnerable to pests and pathogens and damage from frigid temperatures. 

2. Artificial buildings and monuments

Acid rain effect on monument | Image Credit: The Good Planet

Acid rain can erode metallic structures and peel away the components that make up towers and sculptures, causing them to deteriorate. 

Engineers picked sturdy resources like limestone, marble, steel, and brass to withstand acidic corrosions. 

However, the fusion reactions between acid rain and building components resulted in observable deformations disintegrating superstructure like sugar dissolved in a glass of milk.

Since ancient sculptures, statues, and headstones are built mainly of limestones, they are prone to deterioration caused by acid rain. 

The intricacies of a monument can be erased over years of subjection to acid rain, gradually converting them into shapeless sludge.

The carved inscriptions on a few gravestones have also been destroyed by acid rain, leaving them incomprehensible. 

Metallic sculptures are more resistant to physical degeneration from acid rain than marble monuments, but they can still suffer corrosion and staining.

Acidic precipitation with a pH of 3.5 can potentially erode mild steel, galvanized steel, stainless steel, and red brass, according to research published in the journal “Water, Air, and Soil Pollution” by the University of Hong Kong.

Acid rain can erode metallic elements of structures such as bridges that are susceptible to precipitation and mist. 

Acid rain not only fiercely dissolves calcium into rocks but also deteriorates various metals. Bronze, copper, nickel, zinc, and steel varieties are all sensitive elements.

3. Aquatic Life

Acid rain has a significant impact and consequences on streams, ponds, and other water bodies. Acid rain mixed with grassland runoff supplies nitrogen to various aquatic ecosystems, streams, and wetlands. 

Eutrophication is the expansion of algae and plants in the marine environment due to over-enrichment. 

When these aquatic vegetations die, their degradation depletes the oxygen delivery required for ocean organisms to thrive in the marine environment. 

Hence, acid rain’s repercussions on streams and ponds have become a severe ecological issue around the globe.

As a result of increased acid deposition in acid-sensitive locations, ponds, tributaries, and other water bodies become much more acidic than ever before. 

Hence, in the 1960s and 1970s, in various North American and European regions, the health conditions of abundant crayfish and clams generally dwelling in rivers and lakes started deteriorating extensively. 

Acid-sensitive zones are inclined to acidification due to insufficient soil buffering and acid-neutralizing potential. 

In acid-sensitive regions, the elevated aluminum concentrations discharged from sediments frequently end up in reservoirs, waterways, and streams. 

The drained aluminum, combined with the growing acidity in the water sources, can damage fish gills impairing their breathing mechanisms.

Acid rain has been demonstrated to impact fish species composition significantly. When the pH of water sources goes to 4.0-4.5 from 6.0-7.0, it has been noticed that the proportion of marine species drops dramatically. Furthermore, acid rain causes ripples across the food supply and coastal ecosystems.

What are the forms of acid deposition?

Wet and dry acid rain deposition | Diagram Credit: Andrew Dori

1. Wet Deposition

Acid rain is often typically associated with wet deposition. Sulfuric and nitric acids generated in the sky interact with precipitation, snow, mist, or hailstones to fall backward on the earth.

2. Dry Deposition

If there is a lack of humidity in the atmosphere, acidic pollutants and gases can settle as dry deposition from the environment. 

These particles may swiftly settle on structures (rivers, lakes, plants, and houses) or interact with heavier particles in the atmosphere, posing a threat to human life. 

When stored acids are wiped off the structure by the downpour, acidic water rushes through the ground, harming vegetation and fauna, including insects and fish.

The volume of acidity in the environment that falls on the ground due to dry deposition is determined by the quantity of rain in a given region. 

Desert locations, for instance, have a larger ratio of dry to wet deposition than regions that experience multiple inches of precipitation each year.

How to address and minimize acid rain?

Most crucial solution for acid rain | Infographics Credit: Haiku Deck

1. Emissions reduction

Because combustion of fossil fuels is perhaps one of the most cost-effective methods to generate power, nations are currently looking into innovative techniques to burn energy that produces fewer pollutants. 

Countries with the most CO2 emissions must invest more capital and resources into reducing pollution.

Manufacturing companies can go forth with sprinkling a combination of water and crushed limestone onto the smokestack to help ‘wash’ sulfur out of the fumes. 

Catalytic converters that neutralize hazardous compounds from exhaust emissions should be a compulsory standard in automobiles.

2. Find green technologies to fulfill energy requirements

States must encourage investment into alternative energy sources. Hydropower and nuclear technology are two more modern sources of energy. 

Solar energy or windmills have also been opted for a long time in suitable locations to fulfill energy demands. 

All renewable technologies have distinct advantages and disadvantages, which experts must assess before a state employs them. 

3. Conservation of resources

The authorities should provide more incentives to public transportation and persuade individuals to use them effectively instead of driving. Additionally, automobile pollution is reduced through walking, biking, and carpooling.

To wrap up

Only a tiny bit of difference has been made by a few states since acid rain became a unifying issue for conservationists a few years ago. 

Acid rain is a disaster waiting to wreak havoc in the current trends of climate change. If not managed correctly, it might project incalculable devastation soon. 

However, if the general public and governments work together, we can find a sensible remedy immediately.

We are well familiar with all the buzz around acid rain and environmental degradation. Knowing or unknowingly, each of us has contributed to the acidification of precipitation. 

Hence, it is high time for us to be a little more considerate towards the components of the environment that have been facing the perils of our actions. 

(Last Updated on February 18, 2022 by Sadrish Dabadi)

Shradha Bhatta holds a Bachelors’s Degree in Social Work along with a Post-graduate degree in Project Management from Georgian College in Canada. Shradha enjoys writing on a variety of topics and takes pleasure in discovering new ideas. She likes traveling and spending time with nature. She is a very people-person who loves talking about climate change and alerting people to go green!