Changes in atmospheric composition

During nuclear set off at a great height, an immense amount of nitrogen oxides will be released into the atmosphere, greatly raising their normal percentage. This will lead to the destruction of the ozone layer and, after the smoke disperses, the intensity of the lethal ultraviolet radiation which reaches the earth’s surface will also increase several-fold.

Low-altitude nuclear explosions, on the contrary, will cause a higher concentration of ozone – a biologically toxic substance – near the earth’s surface.

Let us examine a few more consequences of the “burning down of civilization”. (Approximately one – sixth of all the urbanized area of the globe – about 240,000 square kilometers –will be burned down in a war involving nuclear weapons with a total capacity of 5,000 megatons). The urban blazes will release poisonous gases like carbon monoxide, cyanide, dioxin and furan. Borne by the wind, they will destroy the surrounding ecosystems.

Tropical forests – the main bearers of organic life on earth and the prime source of oxygen – will be killed even by a brief period of cold and darkness because they exist in a very narrow thermodynamic range and are uncapable of surviving abrupt temperature and lighting fluctuations. This will kill plants and animals, leaving the biosphere without its key source of oxygen.

Even in the event of a 100-megaton explosion over large cities the air temperature at the earth’s surface in the midlatitudes will plummet, remaining below the freezing point of water for three month.

The geography of military operations will also make little difference. If a global; conflict breaks out in the northern hemisphere, the climatic consequences will spread to the southern hemisphere in the next few weeks. In the event of a local nuclear conflict at any point on the globe, the mechanism of the general atmospheric circulation will result in the pollution of the entire earth’s atmosphere within a month or two.

All this means that after a nuclear war, whatever the scenario, the survivers will be exposed to terrible cold, the lack of water, food and fuel, the effects of powerful radiation, pollutants, diseases, in conditions of extreme psychological stress, and all this in twilight, if not in total darkness. Regadless of its scale, nuclear war will either destroy mankind or reduce it to a level below the prehistoric.

I. Ответьте на вопросы к тексту.

1. В чём состоят изменения состава атмосферы в случае ядерного взрыва:

а) на большой высоте?

б) у поверхности земли?

2. Как повлияют ядерные взрывы на:

а) экосистему городов?

б) тропические леса?