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More ice melted from the surface of the Greenland Ice Sheet this year than ever before recorded, report
scientists from the University of Colorado. The same team found that the extent of Arctic sea ice reached the
lowest level in the satellite record in 2002, offering further proof that climate change is already changing the
Arctic.
Researchers from the University of Colorado (UC) say that the speeding up melting appears to be linked to
changes in Northern Hemisphere atmospheric circulation patterns. The study also found temperatures during
the summer of 2002 were warmer than usual over much of the Arctic Ocean.
"It is likely that sea ice extent will continue to decline over the 21st century as the climate warms,"
researchers added. "With these trends, we may see a 20 percent reduction in the yearly average sea ice by
2050, and by then there might be no ice at all during the summer months."
The report was released on Saturday at the yearly fall meeting of the American Geophysical Union, just one
week after an announcement by the National Aeronautics and Space Administration (NASA) that sea ice is
melting about nine percent faster than earlier research had showed, and could disappear entirely by the end of
this century.
"This trend of disappearing Arctic sea ice is one example of the environmental damage that can be linked
to carbon dioxide emissions," said Morgan, "When we have the means to reduce CO2 emissions (散发) and
prevent further damage, we should do our best. National leaders must act now to improve energy efficiency
and increase the use of renewable energy sources, like wind and solar, before it's too late."
UC scientists judge that a change in the Greenland climate toward warmer conditions would lead to an
increase in the rate of sea level rise, which will bring disasters to the human beings.
1. It can be inferred that _____. [ ]
A. scientists have found that Arctic sea ice is lower than before
A. scientists have studied the pictures of the Arctic sent by satellites
B. scientists began to do research on Arctic sea ice in the year 2002
C. warm temperature has hardly any effect on the extent of Arctic sea ice now but soon will
2. Scientists fear that _____. [ ]
A. there will be no ice left at all in the Arctic Ocean at the end of the 21st century
B. disasters will happen if Arctic sea ice continues to melt faster than before
C. the temperature in Greenland will be too warm for animals and human beings to live on
D. people still think Arctic sea ice is melting slowly
3. It is thought that _____. [ ]
A. carbon dioxide emissions are one of the causes of the environmental damage
B. carbon dioxide emissions are an example of the environmental damage
C. most environmental problems are caused by carbon dioxide emissions
D. people can still have the chance to solve the above environmental problem
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