Temperatures around the ____ have been changing for ____ of years. ____ factors play a part. Some ____ act like a ____ blanket around Earth, keeping heat ____. We call them greenhouse gases. They occur ____ in the atmosphere, but we also add some extra. There are ____ in Earth's ____, and its path around the ____. These changes occur in cycles. There are ____ in the amount of energy the ____ gives out. These changes ____ in cycles too. In conclusion, temperatures are ____ much ____ than in the past. We ____ think this is natural. We think the main cause is the greenhouse ____ which we are adding to the atmosphere. But not all scientists ____. Some think the warming is mainly ____. The sun sends out energy as sunlight. This ____ Earth. Earth gives out some of the energy again as heat, which warms the ____ Some of this heat escapes to the ____ atmosphere. But some is ____ by the molecules of greenhouse gases. So the air gets warmer and ____. Average temperatures ____.

Global Warming

由
打印
嵌入

排行榜

视觉风格

选项

切换模板

恢复自动保存：？