Population, natural resources
End of the World
As a result of abnormal weather conditions caused by climate changes (such as hurricanes), about 160 000 people die every year. Within 50 years even one third of all species of plants and animals may die. We are the last generation that can put an end to it.
Earth's atmosphere is made of a gas layer. These gases, which trap heat, allow to maintain life on the Earth. This is natural greenhouse effect without which life on the Earth would be impossible. However, human activity contributes to the escalation of this effect. By burning fossil fuels necessary for the production of energy and for transport, people release milliards of tones of carbon dioxide. It is the main greenhouse gas emitted due to human activity. Changes in the land, for example caused by cutting down forests, also contribute to the increase in CO2 in the environment. For instance, trees naturally absorb CO2, so when they are cut down, all carbon dioxide they absorbed during their life is emitted into the atmosphere.
Furthermore, industry and other branches of human activity increase the number of gases which appear in the atmosphere naturally, such as methane (CH4) coming from the rice growing, animal breeding and waste fermenting on dumps, and nitrous oxide (N2O) which comes mainly from agriculture. Methane has 21 times higher potential for heating climate than carbon dioxide and it contributes to the greenhouse effect in 18%. The potential of nitrous oxide for heating is 310 times higher in comparison with carbon dioxide but it is emitted in less amount and it contributes to greenhouse effect in 6%.
These gases escalate the greenhouse effect, they thicken the natural layer of gases in the atmosphere and contribute to trapping more heat. As a result, temperature rises and upsets the balance of the atmosphere.
Whereas the presence of many greenhouse gases is natural, the pace with which people add them to the atmosphere differs a lot form the natural one. It was estimated that presently the amount of CO2 in the atmosphere is higher than before the industrial revolution during which people started to burn fossil fuels on a large scale. Owing to industrial activity, people also produce new gases such as HFC and PFC (compounds from the group of hydrofluorohydrocarbons).
Although there are doubts about the scale of climate change, there is general consensus that:
There is every likelihood that the mechanism of climate feed-back will result in even faster and irreversible climate changes. In this phenomenon thermal gases absorb rays reflected from the surface of the Earth which causes rise in temperature; secondary effects, associated with the increase in the amount of water vapour in the atmosphere, might cause changes in cloud cover, trapping even more heat, and consequently climate changes. Nobody knows how much time it will take global warming to fulfill the worst-case scenario.