The earth is becoming warmer. How has this come about? There is no doubt that 【小题1】 is human activity that has caused this global warming rather than a 【小题2】 (nature) phenomenon.

All scientists subscribe to the view that the temperature rise is due to the 【小题3】 (burn) of fossil fuels to produce energy. Some byproducts of this process are called “greenhouse” gases, the most important one of 【小题4】 is carbon dioxide. Without the “greenhouse” effect, the earth 【小题5】 (be) too much cooler than it is. So we need those gases. 【小题6】 when we add huge quantities of extra carbon dioxide into the air, the problem occurs. More heat energy 【小题7】 (trap) in the air causes the global temperature to go up.

However, the attitudes of scientists towards the temperature rise are 【小题8】 (complete) different. Some think the ongoing rise will lead to disasters while others are opposed 【小题9】 the view. They even think more carbon dioxide is actually a positive thing.

Who are right? Only when the fact comes out, 【小题10】 we know it.

In recent years, climate change has had a great impact 【小题1】animals. In 2013, the whole world 【小题2】(shock) by a news photo of a dead polar bear on Norway’s Arctic island of Svalbard. Due to the rise in temperature, the polar bear seemed 【小题3】(die) from lack of food.

According to climate scientists, a key climate process, 【小题4】is called the “greenhouse effect”, includes the “natural” greenhouse effect and the “man-made” green-house effect. The former refers to the fact that heat from the sun 【小题5】(enter) the atmosphere and warms Earth’s surface.

Greenhouse gases in the atmosphere trap some of the heat, 【小题6】(keep) Earth’s climate warm and habitable. However, the latter has become【小题7】big problem. When people burn fossil fuels, more heat energy is trapped in the atmosphere and causes Earth’s surface temperature to rise【小题8】(quick).

The evidence shows that the rise in temperature has led to an increase in extreme weather and natural 【小题9】(disaster) worldwide. Climate scientists have warned that this warming trend will become 【小题10】(bad) if we do not take appropriate measures. The severe situation requires people allover the world to pay more attention to it.

In recent years, climate change has had a great impact on the animals in water or on land. In 2013, a lot of people 【小题1】(shock) by a news photo of a dead polar bear 【小题2】Norway’s Arctic island of Svalbard. Due to the increase in temperature, the polar bear appeared 【小题3】(die) from lack of food.

According to climate 【小题4】(scientist), a key climate process called the “greenhouse effect” has two common meanings: the “natural” greenhouse effect and the “man-made” greenhouse effect. The former refers to the fact 【小题5】heat from the sun enters the atmosphere and warms Earth’s surface. Greenhouse gases in the atmosphere trap some of the heat, 【小题6】(keep) Earth’s climate warm and habitable. However, the latter has become a big problem. When people burn fossil fuels, more heat energy is trapped in the atmosphere and causes Earth’s surface temperature to rise 【小题7】(quick).

The evidence shows that the rise in temperature 【小题8】(lead) to an increase in extreme weather and natural disasters worldwide. It is warned that this warming trend will become 【小题9】(bad) if we do not take appropriate measures. The severe situation requires people all over the world to pay more attention to it, because this is 【小题10】most serious issue affecting all of us on this planet.