Acid Rain Short Essay Example

deposition.

The chemical reactions that lead to the formation of acid rain can occur over a period ranging from several hours to several days. In the past, smokestack pollution used to stay close to the ground and harm nearby land, plants, and animals. To address this issue, tall smokestacks were constructed under the belief that sending pollution high into the air would solve the problem. However, it is now understood that this approach is incorrect because it actually prolongs the presence of pollution in the air and increases the chances of acid rain formation.

Furthermore, wind can carry these pollutants over long distances before they combine with water droplets to form acid rain. As a result, areas far away from polluting smokestacks can also be affected by acid rain. Dry deposition of pollutants tends to be more common near cities and industrial areas where emissions occur. Additionally, there are natural sources of acids like volcanoes, natural geysers,and hot springs.
Nature has mechanisms to recycle and break down natural acids, which only contribute a small portion to global acidic rainfall. In small quantities, these natural acids even help dissolve nutrients for trees and plants. However, human activities produce excessive amounts of acids that disrupt this natural acidity balance. Acid rain or acid precipitation is rainfall with a pH level below 5.6 and remains a highly debated topic due to its global environmental impact. Over the past decade, countries like the United States, Canada, and parts of Europe have experienced extensive damage to lakes and streams due to acid rain. Acid rain occurs when nitrogen and sulfite oxides combine with moisture in the atmosphere, resulting in nitric and sulfuric acids.

The primary sources of acid rain are sulfur dioxide released during the burning of fossil fuels containing sulfur. Various industrial processes such as iron and steel production, utility factories, and crude oil processing generate sulfur dioxide gas. Smelting metal sulfate ore in iron and steel production also releases sulfur dioxide used in obtaining metals like zinc, nickel, and copper. Natural disasters like volcanoes, sea spray, plankton,and decaying vegetation contribute 10% of all sulfur dioxide emissions into the atmosphere.
Industrial combustion is responsible for 69.4% of sulfur dioxide production, whereas transportation only contributes 3.7%. Nitrogen oxide also plays a significant role in the formation of acid rain, which occurs due to high-temperature firing processes in automobiles, utility plants, and chemical industries involved in fertilizer production. Natural processes like bacterial action in soil, fires, volcanic activity, and lightning contribute about five percent of nitrogen oxide emissions.

Transportation is accountable for 43 percent of nitrogen oxide emissions while industrial combustion accounts for 32 percent. Nitrogen oxide itself is hazardous. Acid rainfall refers to precipitation with a pH level below 5.6 and can be distinguished from regular precipitation based on its pH level. The pH scale ranges from zero to fourteen and indicates acidity or basicity; numbers below seven indicate acidity while numbers above seven indicate basicity. The scale uses different colors according to various pH levels.

Organisms are minimally affected within the safe zone of pH 6.5 to 8. A pH level of seven represents neutrality associated with pure water.The acidity of acid precipitation depends on emission levels and chemical mixtures of sulfur dioxide and nitrogen oxides present in the atmosphereSulfur dioxide and nitrogen oxides undergo complex reactions in both the

gas phase and aqueous phase before transforming into corrosive components found in acid rain. There are multiple potential reactions that contribute to the oxidation of sulfur dioxide in the atmosphere, each with varying effectiveness. The predominant process involves sulfur dioxide reacting with moisture in the air, leading to immediate formation of a sulfite ion. This occurs as sulfur dioxide combines with airborne hydrogen atoms, resulting in the creation of sulfuric acid. A common method for converting sulfur dioxide into sulfuric acid involves ozone-induced oxidation, which occurs at a favorable rate and can be a major factor in sulfuric acid production. While there are additional minor reactions contributing to acid rain, their impact is minimal due to various reasons. These reactions primarily take place within the gas phase. The oxidation of sulfur dioxide is most commonly observed within clouds and heavily polluted air where ammonia and ozone compounds are abundant; these catalysts play an essential role in converting more sulfur dioxide into sulfuric acid. However, not all of the sulfur dioxide goes through conversion; a significant amount can remain suspended in the atmosphere, travel to different regions, and return to Earth without undergoing any changes.In a similar way, nitrogen oxides are also released into the atmosphere and undergo oxidation within clouds, leading to the formation of nitric or nitrous acid. These reactions take place in heavily polluted clouds that contain small amounts of iron, manganese, ammonia, and hydrogen peroxide. Nitrogen oxides primarily enter the atmosphere through automobile exhaust emissions. Once they are present in the air, they react with water molecules and produce nitric or nitrous acid.

Scientists have observed slower growth rates in certain forests without

any known cause. Trees are growing at a decreased rate and their leaves and pine needles prematurely turn brown and fall off instead of remaining green. Acid rain has been identified as the reason for this change over time. When it rains, water from summer springs washes away the leaves causing them to fall onto the forest floor. Some of this water is absorbed by the soil and can flow into nearby bodies of water.

The soil possesses buffering capacity which helps counteract the acidity in rainwater. If not for this capacity, soil pH would quickly change. States like Nebraska and Indiana have well-buffered soil while mountainous regions like Adirondack mountains lack acid-neutralizing abilities resulting in high pH levels in their soil. This high pH accelerates soil weathering and increases solubility of harmful elements such as aluminum.
High concentrations of aluminum hinder plants' ability to absorb nutrients from the soil, weakening trees through leaf destruction and limited nutrient availability. In addition, when acid rain falls, harmful substances seep into the ground through tree roots, further poisoning them. Acidic rainwater dissolves nutrients and beneficial minerals from the soil before they can be used for plant growth. Furthermore, acid rain not only depletes plant nutrients but also releases toxic substances like aluminum into the soil due to hydrogen ions dissolving rocks and soil particles that typically bind metals to the soil structure. Frequent acid rain has detrimental effects on both land organisms and those in aquatic biomes as leaves lose their protective waxy coating due to acid rain, making plants more susceptible to disease. Consequently, weakened plants struggle to produce enough food energy for their health, leaving them vulnerable

to disease, insects, and cold weather that can ultimately lead to their demise. Moreover, not only does acid rain negatively impact land organisms but it also affects aquatic ecosystems. Normally lakes and streams have a pH level between six and eight with some being naturally acidic without the influence of acid rain. Acid rain can enter lakes through various pathways: certain chemical substances exist as dry particles in the atmosphere while others directly enter through precipitation.Furthermore, acid rain can be detrimental to the environment in several ways. When acid rain falls on land, it can be drained into lakes through sewage systems. Additionally, during spring acid shock, acids from melted acid snow can seep into lakes and enter the ground. This runoff then flows into streams and lakes.

The reproductive season for many species occurs during spring when they are particularly sensitive to changes in pH levels caused by acid rain. The increased acidity during this period poses hazards as it can lead to severe deformities in offspring. It is generally observed that younger individuals within most species are more susceptible compared to older members of the same species.

Different species have varying levels of tolerance for acidity. For example, frogs are able to tolerate high acid levels, while snails are more sensitive to pH changes. Acid molecules present in water hinder fish gills' oxygen absorption by creating mucus, disrupt salt balance in fish tissue, and cause calcium deficiency.

This calcium deficiency negatively affects reproduction and leads to weak or brittle eggs and spine weakness with bone deformities. Moreover, acid rain carries nitrogen-rich fertilizers from land which promotes algae growth that increases fish mortality rates and depletes oxygen

supply further harming aquatic ecosystems.

Apart from its impact on living organisms, acid rain also damages man-made materials such as marble, limestone, sandstone, metals, paints,textiles ceramics leather,and rubber by dissolving them or causing corrosion. While natural deterioration occurs over time with unpolluted rain exposure for these materials too;acid rain accelerates this process significantly.
The reaction of acid rain with calcium sulfate in limestone causes stone carvings to lose their features, while the introduction of protons results in iron oxide formation when oxygen is present. The cost of repairing buildings and monuments damaged by acid rain is high; in 1990, the United States spent $35 billion on paint damage caused by acid rain. Acid rain repairs for the Cologne Cathedral in Germany cost approximately $20 million in 1985, and the Romans spent about $200 million on acid rain repairs for their monuments. Acid rain also has negative effects on human health, causing harm through exposure to the atmosphere and contaminated soil used for growing food. When acid rain occurs, toxic metals separate from their natural compounds. While these metals are dangerous alone, they become harmless when combined with other elements. Humans can consume toxic metals through drinking water, crops, and animals they eat, which can lead to nerve damage, severe brain damage, or even death. There is a suspected connection between aluminum and Alzheimer's disease as well. Acid rain poses serious health risks such as respiratory problems like dry coughs, asthma, headaches, and irritation of the eyes, nose,and throat. People with existing respiratory issues are especially vulnerable to the harmful effects of polluted rainfall.However,even those without respiratory difficulties may suffer lung damage from air pollutants caused by acids

that could potentially be fatal.`In 1991, the United States and Canada implemented an air quality agreement with the goal of reducing sulfur dioxide emissions. As part of this agreement, the US committed to decreasing their yearly sulfur dioxide emissions by approximately ten million tons before 2000. Prior to this agreement, the Clean Air Pact Amendment was introduced a year earlier to target nitrogen oxide emissions. This amendment specifically focused on automobiles and coal-fired electric utility boilers as the main sources of nitrogen oxide pollution.

To effectively decrease vehicle emissions, it is crucial to install catalytic converters. These converters play a vital role in reducing nitrogen oxide levels since cars are responsible for emitting most of it. Catalytic converters are positioned on the exhaust pipe to ensure that all exhaust passes through them. They have a dense structure resembling honeycomb coated with platinum, palladium, or rhodium which aids in converting nitrogen oxides, carbon dioxides, and unburned hydrocarbons into cleaner forms.

Utility plants need to follow several steps in order to comply with the Clean Air Act Amendment and reduce sulfur dioxide emissions. One method involves undergoing a coal cleaning process prior to combustion. Another approach is burning low-sulfur content subbituminous coal before combustion occurs to lower sulfur dioxide levels.This text discusses the use of the Fluidized Bed Combustion technique to minimize sulfur dioxide release during combustion, despite its high cost due to subbituminous coal's high demand. The technique involves mixing crushed limestone or sandstone beds into the fuel, resulting in a 90 percent reduction in sulfur dioxide. After combustion, wet flue gas desulfurization takes place through a bottom boiler web scrubber, where limestone reacts with sulfur dioxide and

effectively reduces emissions. Different materials like limestone or sodium hydroxide are used in the scrubber to react with sulfur dioxide, with limestone being more commonly used. Scrubbing removes pollutants from flue gas and emits cleaned flue gas while disposing of waste solids. The text emphasizes the environmental damage caused by acid rain, including forest destruction, pollution of lakes leading to decreased animal populations and food scarcity for humans who rely on animals for sustenance. Furthermore, acid rain can also harm homes and cherished monuments.To reduce emissions of sulfur and nitrogen dioxide, citizens can take steps such as carpooling, using public transportation, or walking, which significantly reduces nitrogen oxide emissions. Conserving energy by turning off unnecessary lights and using less air conditioning and heating benefits the environment as it reduces the use of fossil fuels, which contribute to acid rain. Another effective measure is replacing old appliances and electronics with energy-efficient ones. Power plants can also adopt alternative power sources such as geothermal energy, solar power energy, wind energy, and water energy to further reduce emissions.

In conclusion, sulfur dioxide and nitrogen oxide are the main sources of acid rain. Nitrogen oxide emissions primarily come from automobiles while utility factories are the main sources of sulfur dioxide emissions. These gases evaporate into the atmosphere and oxidize in clouds to form nitric or nitrous acid and sulfuric acid. When these acids precipitate back to earth, they not only damage the environment but also pose a risk to human health. Acid rain leads to plant life death and destruction in lakes and ponds. The pollutants in acid rain also cause respiratory problems in humans, both indirectly through consuming contaminated

food and directly when inhaling them.

Governments have implemented legislation aimed at decreasing emissions of sulfur dioxide and nitrogen oxide;If we do not collectively prevent the discharge of harmful pollutants, the effectiveness of these measures will be compromised. The continuous destruction caused by acid rain in the environment will eventually lead to our downfall.