Effects of Acid Rain on Humans

Acid rain looks, feels, and tastes just like clean rain. The harm to people from acid rain is not direct. Walking in acid rain, or even swimming in an acid lake, is no more dangerous than walking or swimming in clean water. The air pollution that causes acid rain is more damaging to human health. Sulfur dioxide and nitrogen oxides, the major sources of acid rain, can irritate or even damage our lungs.

The pollutants that cause acid rain can also reduce visibility, limiting how far into the distance we can see. The primary pollutants associated with acid rain and poor visibility are human-made sulfur dioxide emissions. These emissions form small sulfate particles, or aerosols, in the atmosphere. These aerosols reduce visibility by scattering light. Sulfate aerosols are the main cause of poor visibility in the eastern United States.

Nitrogen oxide emissions are also associated with the acid rain problem. They, too, can form aerosols in the atmosphere that significantly reduce visibility. Nitrate aerosols are often the main cause for poor visibility in the western United States where sulfur dioxide emissions and humidity are lower than in the east.

Making Acid in the Air

The final concentration of acids (mainly sulfuric acid, H₂SO₄ and nitric/nitrous acid, HNO₃/HNO₂) in precipition (acidity) is dependent on emissions of SO₂ and NO_x from sources, weather conditions andother chemicals present in the atmoshpere. The formation of sulfuric and nitric/nitrous acid in the atmosphere is a complex process involving several chemical reactions involving both solution and gas phase reactions.

SO₂

Gas phase	Solution phase
2SO2 + O2® 2SO3 very slow in the absence of a catalyst, therefore this is not a significant contributor	1) SO2 (aq)® H+ + HSO3- 2) HSO3- (aq)® H+ + SO32- The equilibrium concentraions for the above reactions are dependent upon such things as pH, droplet size, the "sticking coefficient" for SO2 on water, etc.
2SO3 + H2O® H2SO4 occurs quickly, therefore any formation of SO3 in the moist atmosphere is assumed to lead to the formation of sulfuric acid	1) HSO3- + H2O2® A- + H20 2) A- + H+® H2SO4 The dominant oxidation process occurs by hydrogen peroxide (formed in the gas phase from free radicals). The reaction involves the formation of an intermediate (A-), possibly a peroxymonosulfurous acid ion
1) HSO3- + H2O2® A- + H20 2) A- + H+® H2SO4 The dominant oxidation process occurs by hydrogen peroxide (formed in the gas phase from free radicals). The reaction involves the formation of an intermediate (A-), possibly a peroxymonosulfurous acid ion

NO_x

Gas Phase	Aqueous Phase
HO + NO2 (+M)® HONO2(+M) the principal contributor to the formation of nitric acid is the reaction with hydroxy radicals. These radicals are highly reactive and abundant in the atmosphere.	1. 2NO2(g) + H2O(l)® 2H+ + NO3- + NO2- 2. NO(g) + NO2(g) + H2O(l)® 2H+ + 2NO2- 3. 3NO2(g) + H2O(l)® 2H+ + 2NO3- + NO(g) Equilibria of three reactions define the aqueous oxidation of Nox and depend on the partial pressures of NOx present in the atmosphere, temperature, humidity and the low solubility of NOx.

What Region of the United States Is Most Affected by Acid Rain?

Acid rain didn't become an environmental problem until the burning of large quantities of fossil fuels during the industrial age. Some acid rain occurs naturally, but sulfur dioxide and nitrogen oxide emissions from smokestacks combine with rain to make sulfuric and nitric acid in amounts that harm the environment. The region of the United States most harmed by acid rain is the East Coast, including the Appalachian Mountains and the Northeast.

Lakes and Streams

In a study of the nation's lakes and streams that show acidic conditions, the National Surface Water Survey found that acid rain caused the acidity in 75 percent of the lakes and about 50 percent of the streams. Greatest acidity occurred along the Atlantic coast, where waters have naturally higher acidity to begin with. The highest rate of stream acidity, over 90 percent, occurs in the New Jersey Pine Barrens region. Little Echo Pond in Franklin, New York, had one of the most acidic conditions, according to the study, with a pH of 4.2.

Forests and Soils

Acid rain degrades soils by washing away chemicals such as calcium and magnesium, which buffer acidity and provide essential nutrients to plants. Acidity also releases potentially toxic dissolved aluminum into water. Appalachian forests from Maine to Georgia are particularly affected. Trees usually don't die outright but are weakened and more susceptible to pathogens, insects, drought or extreme cold. Scientists expect that the U.S. Environmental Protection Agency's Acid Rain Program, which reduces sulfur dioxide emissions, will significantly reduce acidification along the East Coast.

What Place in the World Receives the Most Acid Rain?

Acid rain is responsible for severe environmental destruction across the world and occurs most commonly in the North Eastern United States, Eastern Europe and increasingly in parts of China and India. According to the Environmental Protection Agency (EPA) acid rain can be particularly damaging to the young from many species of plant and wildlife.

What is Acid Rain?

Nitrogen oxide and sulfur dioxide are polluting byproducts of soft-coal-burning power plants and factories, and are the main culprits in the production of acid rain. When these chemicals combine with water and particulates in the atmosphere, the result is precipitation, which includes rain, snow and fog, laden with nitric and sulfuric acids, otherwise known as acid rain.

The Black Triangle

Covering areas of the Czech Republic, Germany and Poland, the Black Triangle is an area that received heavy acid rain throughout the 1970s and 80s. In parts of the Black Triangle, entire forests were dead or dying and even railroad tracks were being corroded by the acidic precipitation. The emissions of coal-burning factories in Eastern Europe came under strict regulation by the Geneva Convention of 1979 to prevent further acid rain pollution, a measure that has been successful in significantly reducing acid deposition in the region.

Eastern United States

Parts of the Eastern United States were also once plagued by some of the highest levels of acid rain in the world, due to emissions from Midwestern coal-burning power plants. In parts of New Jersey, for example, over 90 percent of freshwater streams are still acidic today due to acid rain, according to the U.S. Environmental Protection Agency. While the effects of acid rain are still felt in the region, acid rain itself has significantly decreased as a result of the Clean Air Act of 1970 and its subsequent amendments.

Changing Trends

Because of the laws enacted in the United States and Europe regulating emissions from coal-burning factories, and the adoption of mitigating technologies, such as limestone injection burners, reburners, flue gas desulphurizers and low-sulfur burners, these areas receive less acid rain today than in the past, according to a report from the environmental watchdog group Earthwatch Institute. The habitats in these countries suffered extensive damage and recovery is slow, but international concern over acid rain has since shifted focus to other parts of the world. In China and India, rapid industrial growth and lax pollution regulations could combine to produce the highest levels of acid rain in the developing world.

Acid Rain in Asia

Since the year 2000, levels of nitric and sulfuric acid in precipitation have been steadily increasing in Asian cities such as Beijing and New Delhi as domestic demand for electricity and manufactured goods increases. Without pollution regulations on the rapid industrial growth in the developing nations of China and India, acid rain could continue to grow in potency and reach until a similar crisis level as seen in Europe and the United States in the 1980s, according to a report by Science News.

Solutions and Ways Forward

In the United States, there are measures to protect the environment from the effects of acid rain including the EPA's Acid Rain program developed following the Clean Air Act Amendment of 1990 which aims to lower sulfur dioxide emissions from power plants. Responsible steps like these, towards lowering contaminants in the air can help to halt the destruction of acid rain.

Alternate Ways to Reduce The Acid Rain

Acid rain is a very serious environmental threat faced by our planet today. Millions of people get affected by it on a daily basis. Acid rain occurs when high levels of sulfur dioxide and nitrogen dioxide enter in the atmosphere and start undergoing chemical transformation. These harmful gases are absorbed by water droplets in the clouds and they fall on the earth during rains. They can damage the natural soil by increasing the acidity levels and pollute rivers and lakes. Acid rain is actually a broad term which is used to describe different types of acid that fall from the atmosphere on earth. It's mainly divided into wet and dry. Parts of the world which experience wet weather have acid rain, acid snow and fog. Other parts which experience dry weather for most of the year experience acid gas and acid dust.

Today people can see the effects of acid rain everywhere they go. Dead and weakened trees are a very common sign of acid rain, while in cities worn off or scarred buildings are also a result of acid rain. This problem is more prevalent in the northern hemisphere where there's a huge growth in the number of industries. Winds absorb more and more quantities of harmful gases produced by various kinds of industries. In addition to this, even natural sources like volcanoes, forest fires and lighting contribute to this man-made pollution.

How to Prevent Acid Rain

Acid rain has existed since the beginning of the Industrial Revolution which also marked the start of various factories. The harmful rain was discovered by an English scientist, Robert Angus Smith who came up with the term 'Acid Rain' in 1872, when he saw corrosion on the surfaces of buildings and plants because of rain. However, acid rain became an important government issue only after six to seven decades. 1980 marked the beginning of the 'Acid Deposition Act' in which environmental agencies started monitoring areas which were effected by acid rain. Since then a lot of research has been conducted and common people like us can do a lot to help environmental agencies prevent acid rain. Here are some pointers.

One of the main causes of acid rain is a sudden drop in the pH levels of water and that happens because of absorption of harmful gases by the atmosphere. The best way to restore the pH balance of water is to limit the use of items which run on gasoline. Instead use products which run on electricity; as they are much easier to run and maintain.

Another great thing that all people can do is to learn how to drive cars efficiently. While driving on roads there are a lot of things that can be done to reduce smoke emission from cars. Drivers should ease up as soon as the yellow light rather than slamming on the brakes and they shouldn't rush away as soon as the lights turn green. These small practices help reduce the wastage of gasoline and helps people save a lot of money on fuel.

Learn about the different sources of energy besides fossil fuels and try to implement them in daily usage. Many nations like France and Germany are using electrical, nuclear, wind and sun energy on large basis which has helped cut down on the pollution levels.

Another great tip which almost all of us can practice is to always keep the vehicle tires inflated. Tires having proper pressure will provide users with a better fuel economy.

Limit the use of buses or cars for small things, people can also make use of cycles or walk to cover small distances.

Turn off your lights, computers and other appliances when not in use and turn the thermostat of the house at 68°F in winter and 72°F in summer when the house is empty.

Nowadays, though people don't hear about acid rain anymore, it's still a global problem faced by many nations. It's very unfortunate to see that humans are the ones who have a very important role to play in this destruction.

Acid Rain

Showing  You  How  Environment  Reacts to us Polluting  Humans. Acidic Coffee is a Stimulant and Acid rain is a Death Warrant.

Acid rain is quite a popular term these days. Environmental scientists describe it as an adverse effect of increasing pollution due to recent human activities. But even before humans started evolving on earth, proof of acid rains have been found. It was around 250 million years ago; the most devastating case of mass extinction in earth’s history was caused by acid rain due to volcanic eruption in the Siberian region. It eradicated around 90% of marine and 70% of terrestrial species.

Acidity of rain is measured using the pH scale. The scale considers water as neutral (pH - 7). A pH of less than 7 is acidic and a pH greater than 7 is basic. Coffee is slightly acidic (pH - 5.5) whereas lemon juice is more acidic (pH - 2.5). This is a logarithmic scale, which means pH 4 is 10 times more acidic than pH 5 and 100 time more acidic than pH 6.

Surprisingly, rain is always acidic compared to water. Carbon dioxide in the atmosphere gets dissolved in the clouds to form a weak acid called carboxylic acid. So scientists consider a pH of 5.6 as neutral pH in the case of rainwater. Sulphur dioxide and Nitrogen dioxide, emitted from cars and various industries, make rainwater more acidic. Falling raindrops capture significant amount of these gasses and particles suspended in the air to form a complex mixture before arriving on the ground.

So how acidic could rainwater be? Studies say it could be as low as pH 2. This highly acidic water can directly affect human eye and skin. Fish and amphibians can die instantly. Leeching of nutrients from soil due to long term acidic rains leads to destruction of forest ecosystems. But fortunately, rains with high acidity are very rare. Alarmingly, acidic rains in highly polluted cities are being recorded all over the world.

Does Acid Rain Have an Effect on Agriculture?

Acid rain affects plants directly and decreases soil quality to reduce yields from agriculture. Its effects are particularly severe in locations near sources of sulfur dioxide and nitrogen oxides. In the United States, about two-thirds of sulfur dioxide and one-quarter of nitrogen oxides come from power generation plants burning fossil fuels, while the rest is from industrial and transportation sources.

Sources

Acid rain comes from chemical reactions in the atmosphere among oxygen, water and sulphur or nitrogen oxides. When sulfur dioxide dissolves in small droplets of water in clouds, it reacts with the hydrogen and oxygen of the water to form a weak solution of sulfuric acid. Similarly, nitrogen oxides form weak nitric acid in water droplets. The clouds can drift over hundreds of miles carrying their acid droplets. When conditions are right for rain, the droplets grow and fall to the ground. In many areas of the United States, such as the great plains, the acid rain falls mostly on land used for agriculture.

Plants

Acid rain influences both the quality and yield of agricultural products. Acid rain can damage the leaves of vegetables such as spinach and cause blemishes on delicate products such as tomatoes. The production and quality of root vegetables is reduced. The damage depends on the strength of the acids in the acid rain and the frequency with which the crops are exposed. In addition to cosmetic damage, there is the possibility that crops grown under acidic conditions have lower nutritional value with fewer minerals.

Soil

The acidic nature of acid rain leaches plant nutrients out of the soil and can make it less productive for agriculture. Soils with high alkaline content, such as those containing calcium carbonate or limestone, can neutralize the acids and are less sensitive. Other soils normally contain the minerals that plants need, but the acid in acid rain dissolves them and replaces the metallic ions with hydrogen. When the plants absorb water that normally contains the minerals, they get hydrogen instead and can't grow as large or as quickly as before. In severe cases, this lack of minerals can kill the plants.

Reduction

The U.S. Environmental Protection Agency has taken steps to reduce emissions of sulphur dioxide and nitrogen oxides and continues to monitor these pollutants. Car manufacturers are required to produce cars that emit less of these damaging gases and power plants have to install filters to reduce emissions. As an individual, you can reduce your use of electric power and make sure that the catalytic converter on your car is working properly. Smaller cars and cars with smaller engines produce less carbon dioxide. Insulating your home, using efficient heating and cooling systems and avoiding heating with oil can make a substantial contribution to reducing the effects of acid rain on agriculture.

Acid Rain: Scourge of the Past or Trend of the Present?

Acid Rain

It was a problem that largely affected U.S. eastern states. It began in the 1950s when Midwest coal plants spewed sulfur dioxide and nitrogen oxides into the air, turning clouds–and rainfall–acidic. As acid rain fell, it affected everything it touched, leaching calcium from soils and robbing plants of important nutrients. New England’s sugar maples were among the trees left high and dry.

Acid rain also poisoned lakes in places like New York’s Adirondack Mountains, turning them into a witches’ brew of low pH waters that killed fish and brought numbers of fish-eating birds like loons to the brink.

Then in 1970, the U.S. Congress imposed acid emission regulations through the Clean Air Act, strengthened two decades later in 1990. By the 2000s, sulfate and nitrate in precipitation had decreased by some 40 percent.

Is it Back?

Has acid rain now blown over? Or is there a new dark cloud on the horizon?

In findings recently published in the journal Water Resources Research, Charles Driscoll of Syracuse University and the National Science Foundation’s (NSF) Hubbard Brook Long Term Ecological Research (LTER) site in New Hampshire reports that the reign of acid rain is far from over.

It’s simply “shape-shifted” into a different form.

Hubbard Brook is one of 26 NSF LTER sites across the nation and around the world in ecosystems from deserts to coral reefs to coastal estuaries. Co-authors of the paper are Afshin Pourmokhtarian of Syracuse University, John Campbell

of the U.S. Forest Service in Durham, N.H., and Katharine Hayhoe of Texas Tech University. Pourmokhtarian is the lead author.

Acid Rain First Identified

Acid rain was first identified in North America at Hubbard Brook in the mid-1960s, and later shown to result from long-range transport of sulfur dioxide and nitrogen oxides from power plants. Hubbard Brook research influenced national and international acid rain policies, including the 1990 Clean Air Act amendments. Researchers at Hubbard Brook have continued to study the effects of acid rain on forest growth and on soil and stream chemistry.

Long-term biogeochemical measurements, for example, have documented a decline in calcium levels in soils and plants over the past 40 years. Calcium is leaching f

rom soils that nourish trees such as maples. The loss is primarily related to the effects of acid rain (and acid snow).

Now, Hubbard Brook LTER scientists have discovered that a combination of today’s higher atmospheric carbon dioxide (CO2) level and its atmospheric fallout is altering the hydrology and water quality of forested watersheds–in much the same way as acid rain.

“It’s taken years for New England forests, lakes and streams to recover from the acidification caused by atmospheric pollution,” says Saran Twombly, NSF program director for long-term ecological research. “It appears that these forests and streams are under threat again. Climate change will likely return them to an acidified state. The implications for these environments, and for humans depending on them, are severe.”

Climate projections indicate that over the 21st century, average air temperature will increase at the Hubbard Brook site by 1.7 to 6.5 degrees Celsius, with increases in annual precipitation ranging from 4 to 32 centimeters above the average from 1970-2000.

Monitoring the Effects

Hubbard Brook scientists turned to a biogeochemical model known as PnET-BGC to look at the effects of changes in temperature, precipitation, solar radiation and atmospheric CO2 on major elements such as nitrogen in forests. The model is used to evaluate the effects of climate change, atmospheric deposition and land disturbance on soil and surface waters in northern forest ecosystems.

It was created by linking the forest-soil-water model PnET-CN with a biogeochemical sub-model, enabling the incorporation of major elements like calcium, nitrogen, potassium and others.

The results show that under a scenario of future climate change, snowfall at Hubbard Brook will begin later in winter, snowmelt will happen earlier in spring, and soil and stream waters will become acidified, altering the quality of water draining from forested watersheds.

“The combination of all these factors makes it difficult to assess the effects of climate change on forest ecosystems,” says Driscoll. “The issue is especially challenging in small mountain watersheds because they’re strongly influenced by local weather patterns.”

The Hubbard Brook LTER site has short, cool summers and long, cold winters. Its forests are made up of northern hardwood trees like sugar maples, American beeches and yellow birches. Conifers–mostly balsam firs and red spruces–are more abundant at higher elevations.

The model was run for Watershed 6 at Hubbard Brook. “This area has one of the longest continuous records of meteorology, hydrology and biogeochemistry research in the U.S.,” says Pourmokhtarian.

The watershed was logged extensively from 1910 to 1917; it survived a hurricane in 1938 and an ice storm in 1998.

It may have more to weather in the decades ahead.

The model showed that in forest watersheds, the legacy of an accumulation of nitrogen, a result of acid rain, could have long-term effects on soil and on surface waters like streams.

Changes in climate may also alter the composition of forests, says Driscoll. “That might be very pronounced in places like Hubbard Brook. They’re in a transition forest zone between northern hardwoods and coniferous red spruces and balsam firs.”

The model is sensitive to climate that is changing now–and climate changes expected to occur in the future.

In scenarios that result in water stress, such as decreases in summer soil moisture due to shifts in hydrology, the end result is further acidification of soil and water.