Acid rain

What causes acid rain?

Sulfur dioxide is the most important gas which leads to acidification . Emissions of nitrogen oxides which are oxidized to form nitric acid are of increasing importance due to stricter controls on emissions of sulfur containing compounds. 70 Tg(S) per year in the form of SO2 comes from fossil fuel combustion and industry, 2.8 Tg(S) from wildfires and 7-8 Tg(S) per year from volcanoes.

Natural Phenomena

The main natural cause of acid rain is emissions from volcanoes and from biological processes that occur on the land, in wetlands, and in the oceans.

The effects of acidic deposits have been detected in glacial ice thousands of years old in remote parts of the globe.

Human activity

The principal cause of acid rain is sulphuric and nitrogen compounds from human sources, such as electricity generation, factories and motor vehicles. One of the most polluting are coal power plants. The gases can be carried hundreds of kilometres in the atmosphere before they are converted to acids and deposited.

The effects of acid rains

Acid rain causes acidification of lakes and streams and contributes to the damage of trees at high elevations and many sensitive forest soils. In addition, acid rain accelerates the decay of building materials and paints, including irreplaceable buildings, statues, and sculptures that are part of our nation's cultural heritage. Before to falling to the earth, sulfur dioxide (SO2) and nitrogen oxide (NOx) gases and their particulate matter derivatives-sulfates and nitrates-contribute to visibility degradation and harm public health.

Surface waters

The ecological effects of acid rain are clearly seen water environments (lakes, streams and marshes). Falling of acid rain on the lakes, marshes is harmful for fishes and other water habitants. Usually lakes and streams have a pH between 6 and 8. But some lakes are naturally acidic even without the effects of acid rain. Acid rain primarily affects sensitive bodies of water, which are located in watersheds whose soils have a limited ability to neutralize acidic compounds (called "buffering capacity"). Lakes and streams become acidic (i.e., the pH value goes down) when the water itself and its surrounding soil cannot buffer the acid rain enough to neutralize it. In areas where buffering capacity is low, acid rain releases aluminum from soils into lakes and streams; aluminum is highly toxic to many species of aquatic organisms.

Forests

After much researcher's analysis the conclude that acid rains is the reason of forests slower growth, injury, or death. However acid rains are not the onliest reason for this situation and there are also disease, other pollutions, insects, drought, or very cold weather, but anyway they are very harmful. Acid rain do not directly kill the tree, it make the tree be weak by damaging their leaves, limiting the nutrients available to them, or exposing them to toxic substances slowly released from the soil.

Quite often, injury or death of trees is a result of these effects of acid rain in combination with one or more additional threats.

Materials

Acid rain and the dry deposition of acidic particles contribute to the corrosion of metals and the deterioration of paint and stone. These effects significantly reduce the social value of buildings, bridges, cultural objects (such as statues, monuments, and tombstones), and cars.

Human Health

Acid rains is looks, smells, tastes and feels just the same as clean rain. Walking in acid rain, or even swimming in an acid lake, is no more dangerous than walking or swimming in clean water. However, the pollutants that cause acid rain-sulfur dioxide (SO2) and nitrogen oxides (NOx) is harmful. Many scientific studies have identified a relationship between elevated levels of fine particles and increased illness and premature death from heart and lung disorders, such as asthma. and bronchitis. Decreases in NOx emissions are also expected to have a beneficial impact on human health by reducing the nitrogen oxides available to react with volatile organic compounds and form ozone. Ozone impacts on human health include a number of morbidity and mortality risks associated with lung inflammation, including asthma and emphysema.

How to protect from it?

There are several ways to reduce acid rain-more properly called acid deposition-ranging from societal changes to individual action. It is critical that acid deposition be reduced, not only in the Kazakhstan, but also throughout the world to preserve the integrity of natural habitats, as well as to reduce damage to man-made structures. For it first of all people should understand how bad and harmful acid rain is. People should clean up smokestacks and exhaust pipes, use alternative energy sources ( to use other sources of electricity besides fossil fuels: nuclear power, hydro-power, wind energy, geothermal energy, and solar energy.

http://www.epa.gov/acidrain/index.html

http://www.ace.mmu.ac.uk/eae/Acid_Rain/acid_rain.html

en.wikipedia.org/wiki/Acid_rain

http://www.policyalmanac.org/environment/archive/acid_rain.shtml