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1. Introduction
Global warming is a climate change phenomenon which refers to the rise in the average temperature of Earth's atmosphere and oceans due to human-induced greenhouse effect. The term was probably first used in its modern sense in a Science paper called Are we on the brink of a pronounced global warming?(1975) The author's choice of words was new and represented a significant recognition that the climate was warming; while previously the phrasing used by scientists was "inadvertent climate modification". Generally speaking, since the early 20th century, Earth's mean surface temperature has increased by about 0.8 °C, with about two-thirds of the increase occurring since 1980(Greenhouse effect).Evidence for warming of the climate system is overwhelming and observable, such as widespread melting of snow and ice, and rising global average sea level. Ubiquitous as it is, its advent is definitely not a blessing but a Pandora's box with various devastating consequences either for human kind or nature. However, the good news is that this rough problem has become a growing concern of people, and is even on the international agenda. This essay will argue that a fight against the observed warming is looming ahead, and it must be through looking into its both root causes and symptoms to handle the issue. Therefore, initially, the essay will concentrate on the factors behind the phenomenon. Some adverse impacts will follow closely. In the third section, the essay intends to propose several proposals in three angles: (1) the international collaboration is required; (2) the government and public should work together; (3) searching for new paths is necessary. Finally, a conclusion is made that people should keep balance between the development and environment.

2. Causes of temperature changes
Indeed, global warming seems to have long reached a level such that people can ascribe with a high degree of confidence a cause and effect relationship between the greenhouse effect and the observed warming. As matters actually stand, however, the greenhouse gas is little more than a nominal scapegoat, and man himself is to blame for the deadly new ecological crisis.
2.1. The greenhouse effect
Put simply, the greenhouse effect refers to the insulating effect of atmospheric long-wave radiation. It's a process by which thermal radiation from a planetary surface is absorbed by atmospheric greenhouse gases, and is re-radiated in all directions. Since part of this re-radiation is back towards the surface and the lower atmosphere, it results in an elevation of the average surface temperature above what it would be in the absence of the gases.

The earth’s natural greenhouse effect makes life as we know it possible In this mechanism, greenhouse gases play a huge role, and without them, the earth will be as cold and lifeless as the surface of the moon. Accordingly, overload gases will also lead to the hellish conditions now seen on Venus. But unfortunately this delicate balance now seems off, and the home planet risks getting hotter and hotter.

2.2. The greenhouse gases
By their percentage contribution to the greenhouse effect on the earth, the three major gases are water vapor, carbon dioxide and methane respectively. Obviously, water vapor occupies the largest proportion, it's self-innocent and is regulated by water circles for millions本论文由英语论文网提供整理，提供论文代写，英语论文代写，代写论文，代写英语论文，代写留学生论文，代写英文论文，留学生论文代写相关核心关键词搜索。