What are the main causes of global warming?

The main reason for global warming is that humans have used a lot of fossil fuels (such as coal and oil) and released a lot of greenhouse gases, such as carbon dioxide, in the past century. These greenhouse gases cause global warming.

Global warming will redistribute global precipitation, melt glaciers and frozen soil and raise sea level, which will not only endanger the balance of natural ecosystems, but also threaten human survival.

On the other hand, due to the greenhouse gas emissions from the land, the temperature in the mainland rises and the temperature difference with the ocean becomes smaller. Recently, the airflow has slowed down, and the smog can't be blown away in a short time, which has led to an increase in smog weather in many cities, affecting human health.

Extended data

In order to stop the global warming trend, the United Nations specially formulated 1992 "United Nations Framework Convention on Climate Change", which was signed into effect in the Brazilian city of Rio de Janeiro in the same year. According to this convention, developed countries agreed to reduce their carbon dioxide and other "greenhouse gases" into the atmosphere to the level of 1990 by the year 2000.

The greenhouse effect has been working since the formation of the earth. If there is no greenhouse effect, the surface of the earth will be extremely cold, the temperature will drop to MINUS 20℃, the ocean will freeze and life will not form.

Therefore, we are not faced with the problem of whether there is a greenhouse effect, but the problem that human beings emit a lot of greenhouse gases into the atmosphere by burning fossil fuels, which leads to the greenhouse effect and the rapid change of the earth's climate.

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