While acid rain is decreasing thanks to effective regulations by the government, it still poses an environmental threat. To fully understand the impact of acid rain, it’s important to learn the basics about the topic first.

First of all, what is acid rain?

The official definition by the EPA (Environmental Protection Agency) describes acid rain as “a broad term that includes any form of precipitation with acidic components, such as sulfuric or nitric acid that fall to the ground from the atmosphere in wet or dry forms.” In simpler terms, acidic rain refers to rain turned acidic by particles from the atmosphere. 

What are the causes of acid rain? 

The main cause of acid rain is industrial pollution. 

Acid rain stems from the emission of industrial pollutants, including sulfur dioxide (SO2) and nitrogen oxides (NOx), into the atmosphere. The major sources of atmospheric SO2 and NOx are: 

• Power plants / Burning of fossil fuels to generate electricity
• Manufacturing in factories, oil refineries, and other industrial facilities 
• Vehicles and heavy machinery/equipment

Natural disasters can cause acid rain as well. For example, through volcano eruptions, volcanoes can blast pollutants into the air, which would then be carried around the world in jet streams. It would then be turned into acid rain. 

How do we measure acid rain?

You can measure the acidity of acid rain using a pH scale. On the pH scale, the lower the pH equates to the more acidic the substance is. The higher the pH, the less acidic the substance is. 7.0 is considered neutral. 

As you can see from the picture below, the PH of normal rain is around 5.6, and acid rain’s pH is usually between 4.2 and 4.4.

What are the impacts of acid rain on the environment?

Acid rain impacts the environment in various ways. When acid rain seeps through the soil, the acid kills growth enzymes, affecting living creatures and plants. It’s only a matter of time before the acid rain flows into streams and lakes, thus killing marine life. Acid rain also weakens trees by eating away the protective film on leaves, which hinders their growth. 

In urban environments, acid rain can impact buildings and statues by eating away at limestone and marble. The photo below shows a before-and-after picture of a statue affected by acid rain. 

How do we prevent the detrimental effects of acid rain?

The U.S. government took action in the early 1990s and passed a series of regulations that dramatically reduced the emission of sulfur dioxide, therefore also limiting acid rain significantly. However, acid rain is still a prominent environmental issue in other regions such as China and Russia, countries with a vast number of factories but few environmental regulations. 

According to the EPA, other solutions to stop man-made acid rain include restricting the use of fossil fuels and focusing on sustainable energy sources such as solar and wind power. 

Many electricity companies also offer solar packages that require no installation and low costs, which lets people do their part in reducing acid rain.

You can also do your part in reducing acid rain! Here are some tips on how to help your planet:

• Use public transportation.
• Ride a bike.
• Carpool with your friends. 

Citations:

• Bradford, Alina. “Acid Rain: Causes, Effects, and Solutions.” LiveScience, 14 July 2018, www.livescience.com/63065-acid-rain.html. Accessed 26 June 2020.
• Dominguez, Trace. “What Ever Happened to Acid Rain.” Seeker, 29 Sept. 2016, www.seeker.com/what-ever-happened-to-acid-rain-2023245290.html. Accessed 26 June 2020.
• Knight, Will. “Acid rain limits global warming.” NewScientist, 3 Aug. 2004, www.newscientist.com/article/dn6231-acid-rain-limits-global-warming/#:~:text=Acid%20rain%20restricts%20global%20warming,as%20sulphuric%20and%20nitric%20acid. Accessed 26 June 2020.
• “What is Acid Rain?” United States Environmental Protection Agency, www.epa.gov/acidrain/what-acid-rain. Accessed 26 June 2020.
• https://www.nationalgeographic.co.uk/2019/03/acid-rain-explained