Acid Rain 💦💦💦

Kora Saint-Lot

Mr. Youell

Acid Rain

17th March 2015

Causes, Effects & Remedies of Acid Rain

According to US. E.P.A acid rain is a mixture of dry and wet deposited material that comes from the atmosphere containing a higher amount of nitric and sulfuric acids (nitrogen oxides and sulfur dioxide). The sources of the oxides that cause the acid rain are natural, volcanoes and decaying vegetation, and man made, combustion of fossil fuels (as seen in figure 1 and 2).

Figure 1: Factories producing lots of nitric and sulfuric acids.

Figure 2: Volcano spewing gasses into the atmosphere. 

When those previously mentioned oxides are found in the atmosphere they will react with the water in the clouds or the already falling rain and create weak acids known as acid rain. When that rain falls it causes lots of damage to many different things. Such as: buildings, forests, lakes, oceans, rivers and humans. The effect is not limited to only the areas where the most pollution occurs but carried by the wind the gasses can travel great distances and cause damage further away. In highly polluted areas the gasses can be incorporated into the dust and smoke and fall onto the ground. This is called dry deposit, which can be washed away by falling rain and this also increases the acidity.  

Figure 3: Diagram of dry and wet deposition.

When the acid rain falls onto any stone buildings or statues it corrodes it and bit by bit the rock fades. Famous limestone and marble monuments (building and statues from ancient Greece, Rome, Egypt...) are especially in trouble of being eroded. 

Figure 4: Effect of the acid rain on limestone statues.

Entire forests are being affected because the acid in the rain "weakens" the trees, making it easier for them to catch diseases. It also removes nutrients that the tree needs from the soil such as calcium and magnesium. Acid rain deposits nitrates that can lead to increases in nitrogen in forests. Nitrogen is an important plant nutrient, but some forest systems may not be able to use all they receive, leading to nitrogen saturation. In the Eastern United States, there is evidence of nitrogen saturation in some forests. Nitrates can remove additional calcium and magnesium from the soils. Continued nitrogen deposition may alter other aspects of the nutrient balance in sensitive forest ecosystems and alter the chemistry of nearby lakes and streams. The acid that falls directly into lakes and rivers causes the acidity of the water to fall and all living organisms inside the water are affected. Some types of plants and animals are capable of tolerating the change in pH. Some, however, are not able to survive and decrease biodiversity.

Figure 6: Deforestation because of acid rain.

Acid rain is a major problem and solutions are already being found and put into action to help with the pollution in the air that is one of the main causes of it. For example: Scientist have come up with various ways of cleaning the toxic gasses that are being released when fossil fuels are burnt. One of the methods is a machine called "scrubbers". The machines are basically devices that control the pollution by using liquids to wash toxic "pollutants" from the gasses released into the air (see figure  6 for more detailed diagram).

Figure 6: Diagram of the inside of a scrubber.

             Acid rain has become a big problem and people need to start reacting now before it is too late. Most of the damage is caused by human actions and can be reduced but each individual person needs to make a small step in conserving energy. Walking, riding a bike instead of taking a car when possible can be big contributors the the problem since energy production is the biggest cause of acid rain.  If we do not start taking actions now it will soon become irreversible and there will be consequences. Not only to the environment and earth but to us humans living on it.