he system of atmosphere and surface is like a huge "glass greenhouse", which keeps the surface of the earth at a certain temperature all the time, and creates an environment suitable for human and other living things. In this system, the atmosphere can not only let the solar radiation pass through to the ground, but also prevent the loss of ground radiation. We call this protection of the atmosphere on the ground the greenhouse effect of the atmosphere.

Greenhouse gases are called "greenhouse gases". They can allow short wave radiation from the sun to pass through freely, while absorbing long wave radiation from the ground. These gases include carbon dioxide, methane, chlorofluorocarbons, ozone, nitrogen oxides and water vapor, among which carbon dioxide is the most important. In the past century, the global climate is gradually warming, at the same time, the content of greenhouse gases in the atmosphere is also increasing rapidly. Many scientists believe that the intensification of the greenhouse effect caused by a large number of greenhouse gas emissions may be the basic reason for global warming.

Mankind burns coal, oil, natural gas and trees, and generates a large amount of carbon dioxide and methane into the atmosphere, which warms the earth, imbalances the carbon cycle, and changes the energy conversion form of the earth's biosphere. Since the Industrial Revolution, the carbon dioxide content in the atmosphere has increased by 25%, far exceeding all the historical records of the past 160000 years that scientists may have surveyed, and there is no sign of slowing down.

The increase of carbon dioxide emissions in the atmosphere is the root cause of global warming. A survey by the International Energy Agency shows that the carbon dioxide emissions of the United States, China, Russia and Japan account for almost half of the global total. The survey shows that the United States ranks first in the world in terms of carbon dioxide emissions, with an annual per capita carbon dioxide emissions of about 20 tons, accounting for 23.7% of the global total. China's annual per capita carbon dioxide emissions are 2.51 tons, accounting for 13.6% of the global total.