Oil companies must stop exploring for more fossil fuels that the world cannot afford to burn. Governments need to subsidize renewable energy and force polluters to pay.

Acid rains

First of all I should say that the only place on earth where pure water is found is in a laboratory. Rainwater always contains small amounts of impurities. These impurities come from dust particles or are absorbed from the gases in the air. If pure water is exposed to the air it absorbs carbon dioxide to form carbonic acid and becomes slightly acidic, dropping from pH 7 i.e. neutral, to pH 5,6. Even in remote, unpopulated areas rain can reach a pH of 4,5. However, a pH of less than 4,5 in rain is almost certainly caused by air pollution.

Acid rain is caused by the release of the sulphur dioxide and nitrous oxides. The main sources of sulphur dioxide are coal-fired power stations and metal working industries. The main sources of nitrous oxides emissions are vehicles and fuel combustion.

Sulphur dioxide reacts with water vapor and sunlight to form sulphuric acid. Likewise nitrous oxides form nitric acid in the air. These reactions take hours, or even days, during which polluted air may move hundreds of kilometers. Thus acid rain can fall far from the source of pollution.

When mist or fog droplets condense they will remove pollutants from the air and can become more strongly acid than acid rain. Even snow can be acid. Gases and particles, not dissolved in water, with a low pH can also be deposited directly onto soil, grass and leaves. It is possible that even more acidity is deposited in this way than by rain! Not much is known about this process, and it is particularly difficult to study.

There are some undoubted effects of acid rains:

· Acid rains can increase the acidity of lakes, dams and streams and cause the death of aquatic life.

· Acid rain can increase the acidity of soil, water and shallow groundwater.

· Acid rain has been linked with the death of trees in Europe and North America. In spite of a great deal of research, no one yet knows exactly how acid rain harms forests. Most of the forests of Europe consist of huge areas of one tree species. This encourages the spread of plant pests and diseases. It seems likely that acid rain weakens the trees, perhaps helped by other pollutants such as ozone, and then leaves the trees open to attack by disease. Acid rain also disrupts the availability of soil nutrients. The final death of a tree may result from a combination of stresses such as heat, cold, drought, nutrient disruption and disease.

· Acid rains erode buildings and monuments.

· Acid particles in the air are suspected of contributing to respiratory problems of people.

Scientists have many ways to solve this environmental problem. We need to use energy more efficiently at home, in our vehicles and in industry. We will have to think hard about alternative energy sources. It is possible to remove acidic emissions from coal burning, but this is very expensive. It may be possible to breed crops and trees that resist pollution, but this would only be a partial solution. In practice we will probably need a combination of all these ideas and innovations.

Measures of the protection of atmosphere

Measures of the protection of atmosphere are subdivided into three large groups:

· First group: decrease measures of gross amount of contamination, thrown out into atmosphere. This is the improvement of the quality of fuel, using of special liquids in fuel etc. Same group of measures includes perfecting of technological processes including development of the closed cycle production without making of harmful substances into atmosphere.

· The second group includes measures of protection of atmosphere by dispersion, processing and neutralization of harmful wastes.

· The third group of measures assumes prevention of the air contamination by rational placing of the «dirty» enterprises – sources of harmful wastes with consideration of natural conditions and potential possibility of the air contamination.

For realization of atmosphere protection measures the strict state control of air environment, economic and legal stimulation of measures for control of its pollution are also important.

Water pollution

Comprising over 70% of the Earth’s surface, water is undoubtedly the most precious natural resource that exists on our planet. Without the seemingly invaluable compound comprised of hydrogen and oxygen, life on Earth would be non-existent: it is essential for everything on our planet to grow and prosper. Although we as humans recognize this fact, we disregard it by polluting our rivers, lakes, and oceans. Subsequently, we are slowly but surely harming our planet to the point where organisms are dying at a very alarming rate. In addition to innocent organisms dying off, our drinking water has become greatly affected as is our ability to use water for recreational purposes. In order to combat water pollution, we must understand the problems and become part of the solution.

What are the sources of water pollution?

There are many causes for water pollution but two general categories exist: direct and indirect contaminant sources. Direct sources include effluent outfalls from factories, refineries, waste treatment plants etc that emit fluids of varying quality directly into urban water supplies. In the United States and other countries, these practices are regulated, although this doesn't mean that pollutants can't be found in these waters. Indirect sources include contaminants that enter the water supply from soils/groundwater systems and from the atmosphere via rainwater. Soils and ground waters contain the residue of human agricultural practices and improperly disposed of industrial wastes. Atmospheric contaminants are also derived from human practices (such as gaseous emissions from automobiles, factories and even bakeries). Contaminants can be broadly classified into organic, inorganic, radioactive and acid. Examples from each class and their potential sources are too numerous to discuss here.

What are the effects of water pollution?

The effects of water pollution are varied. They include poisonous drinking water, poisonous food animals (due to these organisms having bioaccumulated toxins from the environment over their life spans), unbalanced river and lake ecosystems that can no longer support full biological diversity, deforestation from acid rain, and many other effects. These effects are, of course, specific to the various contaminants.

What are the ways we can take to decrease this problem?

Science provides many practical solutions to minimizing the present level at which pollutants are introduced into the environment and for remediating (cleaning up) past problems. All of these solutions come with some cost (both societal and monetary). In our everyday lives, a great deal can be done to minimize pollution if we take care to recycle materials whose production creates pollution and if we act responsibly with household chemicals and their disposal. Additionally, there are choices we make each day that also can affect the quantity of pollutants our actions will introduce into the environment. Heavily packaged foods, for instance, contain boxes, cartons, bottles etc. made with polluting dyes, many of which are released from groundwater at municipal land fills. Whether we choose to drive to the corner store rather than walk or ride a bicycle will determine how much we personally contribute to acid and hydrocarbon emissions to the atmosphere (and ultimately to global fresh water supplies). In the end, there are many choices on the personal and societal level that we must make (consciously or not) that affect the amount of pollution our town or country will be forced to live with. Our standard of living and very way of life is based upon practices, which are inherently "dirtier" than those of our distant ancestors, although they too polluted their environment to some extent. Without taking a step backward in terms of our standards of living, the answer seems to lie in a combination of many small changes in our daily practices and paying more for goods and services, so that manufacturers of various materials and drivers of automobiles (for instance) will have cleaner devices with which to conduct their activities.