The green house effect occurs when carbon dioxide and water vapor form an invisible blanket around the globe that allows the sun's light to enter, but traps the heat. Green house effect is a process that warms the Earth's surface. When the sun's energy reaches the Earth's atmosphere, some of it is reflected back to the space and the rest is absorbed and re-radiated by greenhouse gases.
While the surface temperatures can vary quite a bit, changes in temperature at the tropopause levels change much slower and are tied more to the time of year.<span>
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