We sometimes think global warming or climate change is a problem very far away from our lives, and that only the government needs to worry about it. But it's hardly possible to completely stay out of it ­ scientists are now 95 percent sure that humans have been the “dominant cause” of global warming trends since the 1950s.
One of the conclusions of a report released on Sept 27 by the United Nations says that human activities have caused global temperatures to rise by 0.89 0C between 1901 and 2012. That might not seem like a lot, but the truth is that a major part of that heat has been absorbed into the oceans, which is not surprising given that they cover two thirds of Earth's surface. Also, water has a much greater capacity (容量) to absorb heat than the air does, according to The Economist.　
While many greenhouse gases occur naturally and are needed to keep the Earth warm enough to support life, humans' use of fossil fuels is the main source of excess (多余的) greenhouse gases. According to CNN, by driving cars, using electricity produced by burning coal and oil or heating our homes with coal or natural gas, we release a large amount of greenhouse gases into the atmosphere.
Your body can barely feel a difference of 0.89 0C, but the Earth's ecosystems are so sensitive that even small changes can disturb them. It often starts with the smallest creatures at the bottom of the food chain, eventually affecting bigger animals, many of which could end up becoming extinct.
Global warming is also linked to an increase in extreme weather. A larger amount of carbon dioxide traps more energy inside the atmosphere. This changes the patterns of storms and rainfall in many regions and can lead to droughts and floods. Worse still, melting sea ice in warmer oceans is causing sea levels to rise at a speed of more than three millimeters per year, according to The Guardian, which also increases the risk of flooding.
“The report should serve as another wake­up call that our activities today have a profound impact on society, not only for us, but for many generations to come，” French Michel Jarraud, secretary­general of the World Meteorological Organization, said at a news conference.
小题1:The underlined word “dominant” in the first paragraph means “ ________”．

A．common	B．indirect
C．secondary	D．leading

小题2:Which of the following statements is TRUE according to the passage?

A．Greenhouse gases have been proven to harm merely the Earth .

B．There is little we can do to prevent global warming.

C．Global warming can increase the chances of droughts and floods.

D．The hugeness of oceans makes them better absorbers of heat than the air.

小题3:The rise in global temperatures between 1901 and 2012 ________.

A．is more harmful to smaller creatures than bigger ones

B．is not serious because most of the extra heat has been absorbed by the oceans

C．has made the Earth's ecosystems more sensitive to changes

D．is likely to cause many species to become extinct

小题4:What is Michel Jarraud's attitude toward the report released by the UN?

A．Negative.	B．Supportive.
C．Doubtful.	D．Uninterested.