Smog or dust dome

Smog or dust dome is most often formed when a layer of cool air is trapped beneath a layer of still warmer air. The mixture of benzopyrene ( a cancer causing substance that is produced by the evaporation of petrol), the waste of hydrocarbons, combined with nitrogen dioxide, oxygen, and sunlight produce the photochemical smog which can be recognized as the yellow cloud over every big city in the world. Besides that optical effect it causes an increase of ozone in the lower atmosphere and the health conditions of the particular organism living in
such an area. For example, it is estimated that “Washington DC receives 10% less sunlight than at the begging of the century due to the shielding of atmospheric pollution.” The ozone enters the leaves of plants turning them brown and makes it difficult for plant to photosynthesize. In addition to that, it causes skin cancer on humans. Most seriously though, it increases the acidity of the rain which is mainly caused by the rise of sulphur dioxide and nitrogen oxides that get caught up by clouds. All ready unpolluted rain is slightly acid due to dissolved carbon dioxide, but polluted rain may be very acidic. The effect of acid rain on terrestrial and aquatic ecosystems can be very different. “In Scandinavia, which receives a high proportion of its air pollution from Britain, once productive lakes are now completely devoid of fish.” In addition to its direct effect on water, acid rain allows metal ions such as aluminum, which is highly toxic to fish, to be leached from the soil . Acid rain reduces the growth of trees and disables plants to photosynthesize which destroys them in the long term. It also reduces the activity of nitrogen-fixing bacteria. In the event of a nuclear accident or war, the main risks do lay only partly in the pollution of air and air as a carrier of the polluted particles. The main risks arise from inhalation of contaminant particles, fallout of radioactive isotopes on soil with subsequent incorporation into food, and contamination of water supplies. The outcome of all those pollutant factors are enormous. The smoke from car engines which contains lead, that causes brain damage in children, stinging eyes, damage of the lung, the death rate of 40.000 asthma patients every year, and the destruction of whole forests includes only a few examples of the effects of air pollution. There are many ways to control and reduce air pollution and it is not the lack of technology but the unwillingness of the humans to change their attitudes and life styles.