Saturday, October 23, 2010

Smog and Acid Rain

Particularly for large metropolitan cities, smog and poor air quality is a pressing environmental problem. Smog primarily consists of carbon monoxide, nitrogen oxides, volatile organic compounds chemically interacting with heat from sunlight forming ground level ozone. Smog is that familiar haze most commonly found surrounding large cities, particularly in the summer time. Smog and ground level ozone contribute to all kinds of respiratory problems ranging from temporary discomfort, asthma, to long-lasting, permanent lung damage. The pollutants in smog come from vehicle emissions, smokestack emissions, paints, and solvents - most of which started out as crude oil.

Much of the eastern United States is affected by another environmental problem known as acid rain. Acid rain can damage crops, forests, wildlife populations, and cause respiratory and other illnesses in humans. When sulfur dioxide and nitrogen oxides react with water vapor and other chemicals in the presence of sunlight, various acidic compounds form in the air and come to the earth as acid rain. The pollutants of acid rain are derived from coal fired power plants. Natural gas emits virtually no sulfur dioxide and up to 80 percent less nitrogen oxides than the combustion of coal. So the increased use of natural gas would provide for fewer acid rain causing emissions.

The source of energy to use for reducing pollution and maintaining a clean and healthy environment is natural gas. Natural gas is also domestically abundant making it a secure source of energy. The environmental benefits of using natural gas over other sources of energy, particularly other fossil fuels are numerous.

Since the use of natural gas emits only low levels of nitrogen oxides and virtually no particulate matter, it can be used to help combat smog formation in those areas where ground level air quality is poor. Electric utilities, motor vehicles, and industrial plants make up the main sources of nitrogen oxides. To combat smog production, especially in urban centers where it is needed the most, increased natural gas use in the electric generation sector, a shift to cleaner natural gas vehicles, and increased industrial natural gas use could all serve to improving the air quality. Summertime, when natural gas demand is at its lowest and smog problems are the greatest, would be a good time for industrial plants and electric generators to use natural gas to fuel their operations instead of using the more polluting fossil fuels. This would effectively reduce smog emissions resulting in clearer, healthier air around the urban centers.

A study conducted in 1995 by the Coalition for Gas-Based Environmental Solutions found that in the Northeast, smog and ozone-causing emissions could be reduced by 50 to 70 percent through the seasonal switching to natural gas.

Particulate emissions such as soot, ash, metals, and other airborne particles also cause the degradation of air quality in the United States. Natural gas emits virtually no particulates into the atmosphere. Emissions of particulates from natural gas combustion are 90 percent lower than from the combustion of oil, and 99 percent lower than burning coal. Increased natural gas use in place of other dirtier hydrocarbons can help to reduce particulate emissions in the United States.

Ocean acidification - Acid rains affecting oceans

Ocean acidification is decrease in the pH in our oceans caused when chemical substances like carbon dioxide (CO2), sulfur, or nitrogen mix with seawater. Ocean pH pH has dropped by slightly less than 0.1 units since industrial revolution and it is estimated that it will drop by a further 0.3 - 0.5 units by 2100, mainly because of carbon dioxide.


Ocean acidification has extremely negative results on some marine creatures like sea urchins, corals, and certain types of plankton as it decreases their ability to harness calcium carbonate which they need to harden their outer shells (exoskeletons). Importance of these creatures is highly important in marine food chain since they provide essential food and habitat to other species and they really represent the base of ocean ecosystems. Researcher Gretchen Hofmann recently said: "It's possible by 2050 they may not be able to make a shell anymore. If we lose these organisms, the impact on the food chain will be catastrophic.

Ocean acidification isn't making oceans significantly more acidic on global scale, but it significantly hurts coastal and shallow area and organisms that live in these areas. There are many factors contributing to acid rains such as farming, livestock husbandry and combustion of different fossil fuels. The most affected areas are usually downwind of coal power plants, on the eastern edges of North America, Europe, and south and east of Asia.

So not only our land hurts because of acid rains, but also our oceans and many marine organisms struggle to cope with increased acidity. And if current rates continue, by the end of this century acidity will be five times bigger than today, and this would really mean catastrophe.


Acid rain - Formation and impact

Acid rain is mostly caused by human emissions of different sulfur and nitrogen compounds which once in atmosphere produce acids. Main reason for acid rains is air pollution as a result of fossil fuels burning. Power plants (especially coal based), factories, cars, they all produce polluting gases and some of them when in atmosphere react with water in clouds to create sulphuric and nitric acids which are very harmful to our environment once they fall on Earth in the form of acid rain.


Acid rain can also take the form of snow, mists and dry dusts, although most common form is rain. The rain isn't always falling just on the polluted area as it can fall many miles away from the source of pollution. Wherever it falls, it has very harmful effect on soil, trees and water.

Acid rain impact can vary, from minimal to severe which depends on the region of the country and on the acidity of the rain as sometimes same amount of acid rains can have different effect in some areas than in others.

Forests exposed to acid rain lose valuable nutrients, trees grow more slowly and sometimes even stops to grow, leaves is damaged as their waxy protective coating wears away because of different acids. These harmful effects combined make trees more vulnerable to different diseases, weather and insects.

Acid rains are most obvious in waters, where they're increasing acidity of water which has tremendous negative impact on water ecosystems, often causing decline of fish and other water population and affecting variety of life in water ecosystems. Most visible effect in these water ecosystems is gradual disappearing of many fish species since their environment becomes intolerable and they're on the lookout for new habitats. Measure of the acidity in certain water ecosystem affected by acid rain is pH value. Here are the effects of an acidified ecosystem on certain pH value.


As water pH approaches
Effects
6.0
  • crustaceans, insects, and some plankton species begin to disappear.
5.0
  • major changes in the makeup of the plankton community occur.
  • less desirable species of mosses and plankton may begin to invade.
  • the progressive loss of some fish populations is likely, with the more highly valued species being generally the least tolerant of acidity.
Less than 5.0
  • the water is largely devoid of fish.
  • the bottom is covered with undecayed material.
  • the nearshore areas may be dominated by mosses.
  • terrestrial animals, dependent on aquatic ecosystems, are affected. Waterfowl, for example, depend on aquatic organisms for nourishment and nutrients. As these food sources are reduced or eliminated, the quality of habitat declines and the reproductive success of birds is affected.

What can be done to stop acid rains? Probably the best answer lies in the alternative energy sources as to avoid harmful burning of fossil fuels but renewable energy sector is still negligible compared to dominant fossil fuels, not only at this moment, but also in years to come.

There's also important to mention that damage done by acid rains can be restored in lake and rivers which can have powdered limestone added to them to neutralize the water - this method is called "liming", but unfortunately isn't used very often because it's very expensive since it needs to be done continuously many times, until the acid rain stops, otherwise its affects are only temporary.

Rich countries Sweden and Norway successfully used this method to restore their lakes and streams. But this solution isn't really a possibility in countries with major acid rain problems (i.e. China) since they have no funds available for this expensive method causing many of their lakes and rivers to stay acidified for many more years and even growing in acidity levels since because of dominant fossil fuels use and its burning these rains continue to fall making this problem more severe with every new acid rain.



Acid Rain - Its Effects and What You Can Do to Help:

Acid rain is relatively unseen and hard to detect, but it is a widespread serious problem that probably affects the area where you live today. Acid rain is defined as rain that has a higher acidic content than normal due to unnatural (human produced) processes. The severity of the problem in your area depends on factors ranging from how close you are to conventional coal-fired power plants, how much rainfall there is total, and upper and lower atmosphere wind currents.

If only the effects of acid rain were as innocuous as the definition! In North America, for example, the problem has progressed so that rainwater can have anywhere from 1000% to 7000% too much acid content. Standing water, where some evaporation has occured, or water that has been absorbed and filtered by the soil can have an even larger acid content. Rainwater that is too acidic can cause many types of problem, such as:

- Acid rain can defoliate trees (making them lose their leaves or needles). This can eventually lead to the tree dying if there is no intervention. Trees can also suffer from stunted growth, and become weakened so that they are vulnerable to weather, disease, and insects.

- When lakes are seriously damaged by acid rain fish die off, birds die from eating "toxic" fish, and humans cannot swim in them

- Buildings and other structures can be corroded by acid rain. In addition, other objects can be affected such as bridges, underground pipes, and artwork on historical buildings.

- Currently, both the railway and airline industries have to be diligent to repair the corrosive damage done by acid rain.

- Humans can become seriously ill and can even die from the effects of acid rain because it can cause respiratory problems, particularly in those who are already vulnerable such as people with asthma.

Acid rain is caused by smoke and gases that are given off by factories and cars. Simply put, the pollutants in the exhaust go into the atmosphere, and become acid that comes back down mixed with rain. A great deal of acid rain is produced when coal is burned to produce electricity. There are ways to clean the coal, called clean coal technology, but these methods are expensive and would probably require government subsidies or new technological breakthroughs to be viable.

Anyone can help reduce the problem of acid rain. You can write to your government official to promote clean coal technology, you can invest in companies that are developing new fossil fuel-free cars, such as fuel cell and electric cars. But most importantly, you can reduce your own consumption of electricity that is produced from coal, drive your gas-fueled car less often, and reduce your own acid rain footprint to make a real difference.


The Devastating Effects Of Acid Rain

Acid rain is an environmental problem that affects areas all around the world. It is the result of sulfur and oxide mixing with moisture for the sky. The pollutants get into the air by fossil fuels, vehicle emissions, and factory exhaust. Acid rain is considered to be one of the largest environmental problems facing the world today.

Acid rain the areas of Europe and North America have seen a dramatic increase in the past decade. Some areas contain anywhere from 10 to 70% more acid than normal. The higher the acid level, the more damage is done to living and non living objects. The environment as a whole suffers. Humans, forests, trees, lakes, animals, and plants all suffer from the effects of acid rain.

Trees are a natural resource. They provide wood, protect against the elements, and provide shelter to wildlife. As trees are destroyed by acid rain, the things that depend on the trees for survival are also affected. It is a downward spiral that continues out of control. Lakes that are damaged by acid rain cause the water and fish to become contaminated. When the fish die, the main source of food for the birds is destroyed. If the area is extremely full of acid rain, the fish eggs may die before even hatching, reducing the amount of food available as well.

Studies are continually being conducted on the effects of acid rain on humans. It can destroy our land and contaminate our food. The main concern is toxic metals. These metals can find their way into drinking water, crops, or animals that we eat. Consuming these items can lead to nerve damage and brain damage. Some researchers think that acid rain can be linked to Alzheimer’s as well.

Respiratory problems in humans resulting from acid rain are common in many areas of the world with high levels of acid. The symptoms include a dry cough, asthma, headaches, and irritations in the eyes, nose, and throat. Taking all this into consideration, the United States and Canada signed the Air Quality Agreement in 1991. The purpose of the agreement is to reduce the effects of acid rain.