It’s been years since people were talking about acid rain. At one point in time, you may have thought that little rain droplets would fall from the sky only to melt off your skin. Luckily, that didn’t happen. But now, nearly 10 years since acid rain was the leading story on the news and the talk of Earth science classrooms everywhere, is acid rain really a problem?
What is Acid Rain?
Acid rain is a type of precipitation that has an unusually low pH. It’s caused by sulfur dioxide (SO2) and nitrogen oxide (NOx) emissions from both man-made and natural events. Acid rain can be rain, snow, sleet, fog, and dew. Back in the 17th and 18th centuries, several Englishmen noticed the deteriorating conditions of marble details on buildings. It wasn’t until the mid-1800s that the relationship between acid rain and air pollution was noted, however, scientists only started studying acid rain in the 1960s.
What Does Acid Rain Do?
Acid rain affects nearly everything. While erupting volcanoes and lightening strikes can bring out the chemicals which create acid rain, the majority of the problem is caused by human activity. Burning fossil fuels accounts for the majority of harsh gases entering our atmosphere. From there, they mix with already forming precipitation and find their way back to Earth. Winds can carry acid rain hundreds of miles. Even if there are no fossil fuel burning plants in a particular area, the effects can still be felt. Areas with high levels of rain are at a greater risk for damage from acid rain.
When this toxic precipitation falls to the ground, it deteriorates trees, shrubbery, buildings, and statues. As it hits the ground, the plants soak up the water (and the chemicals) and the remaining water goes into our runoff, aquifers, and groundwater. While this does effect the clean drinking water supply for humans, there are other concerns as well. The extra acidity in the water creates a reaction with any aluminum particles that have found their way into the environment. The acid rain causes soil to absorb the aluminum which creates many problems for aquatic life. Acidic waters are toxic to shellfish and aquatic mammals. If the increased toxicity doesn’t cause the animal to die, humans who eat these animals (crab, shrimp, crayfish, clams, oysters, mussels) can unintentionally ingest very harmful and poisonous chemicals. Overtime, the bio-accumulation of SO2 and NOx can cause major problems in people.
Is Acid Rain Still A Problem?
In short, yes. Acid rain will always be something we should be concerned about. Although the USA has very strict rules regarding air quality and pollution, other developing countries have not yet put these regulations in place. Toxins from factories in China and India can easily make their way across the ocean and fall as rain or snow in North America. Even if the most stringent laws were enacted tomorrow in every country in the world to stop these gases from being released into the atmosphere, it would still be dozens of years before the harmful effects of acid rain disappeared.