The greenhouse effect has to do with the sun’s heat. But it rests on changes in the Earth’s atmosphere, rather than changes in the sun. The sun’s heat and light pass through the atmosphere. Changes in the atmosphere can affect them.
We live in a global greenhouse. Earth’s atmosphere acts like the greenhouse roof. Heat and light from the sun pass freely through the atmosphere. Then it gives off heat in the form of infrared rays and holds the heat, rather than letting it escape into space. It reduces the change in temperature between day and night, summer and winter. The heat rays of the sun penetrate the air and warm the Earth’s surface during the day. The overlying atmosphere traps this heat so that it escapes more slowly into space, moderating the cold of night. For this reason, the Earth is much warmer than it would be without the greenhouse effect of the atmosphere.
The Earth is surrounded by a blanket of invisible gases such as water vapor, and carbon dioxide that cause the atmosphere to act just like a greenhouse. The sun shines in, and the blanket of gases traps the heat keeping it close to the planet and keeping the surface of the planet warm.
A change in the amount of carbon dioxide would certainly affect Earth’s climate. In fact it is possible that an increase is causing the present warming up of the climate.
Factories, electric power plants, and cars are producing carbon dioxide faster than it can be taken up by the oceans or plants. These added gases are, therefore, capable of trapping more and more of the sun’s heat.
If the Earth’s temperature gets hotter by just a few degrees, it could change the weather all over the planet in big ways. Places that grow most of our food could get too hot to grow crops anymore.
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