Arctic Sea ice melting faster - PAU C.Valenciana inglés 2007

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Climate scientists may have significantly underestimated the power of global warming from human-generated heat-trapping gases to shrink the cap of sea ice floating on the Arctic Ocean. A new study concluded that an open-water Arctic in summers could be more likely in this century than had been estimated in the latest international review of climate research released in February.
“There are huge changes going on,” said Julienne Stroeve, author of this new study. “Just with warm waters entering the Arctic, combined with warming air temperatures, this is causing destruction on the sea ice.”
She also concluded that if emissions of heat-trapping gases like carbon dioxide were not significantly reduced, the region could end up with no floating ice in summers sometime between 2050 and the early decades of the next century.
For the new study, Dr. Stroeve reviewed nearly six decades of measurements by ships, airplanes and satellites estimating the maximum and minimum area of Arctic sea ice, which typically expands most in March and shrinks most in September.
With an expert from the National Center for Atmospheric Research, they then compared the observed trends with the projections made for the United Nations Intergovernmental Panel on Climate Change, using the world’s most advanced computer models of climate.
Dr. Stroeve found that since 1953 the area of sea ice in September has declined at an average rate of 7.8 per cent per decade. Computer climate simulations of the same period had an average rate of ice loss of 2.5 per cent per decade.

ANDREW C. REVKIN
May 1, 2007 - The New York Times

RESPUESTAS

READING COMPREHENSION

I. Answer the following questions using your own words but taking into account the information in the text:

a.    Why is sea ice rapidly disappearing?

• …the power of global warming from human-generated heat-trapping gases to shrink the cap of sea ice floating on the Arctic Ocean… / “Just with warm waters entering the Arctic, combined with warming air temperatures, this is causing destruction on the sea ice.”

b.    How did Dr. Stroeve collect information for her study?

• For the new study, Dr. Stroeve reviewed nearly six decades of measurements by ships, airplanes and satellites estimating the maximum and minimum area of Arctic sea ice, which typically expands most in March and shrinks most in September.

II. Are the following statements true (T) or false (F)? Identify the part of the text that supports your answer by copying the exact  passage on the answer sheet 

a.    This century could see the Arctic Ocean without the cap of sea ice during the summer.

• TRUE: A new study concluded that an open-water Arctic in summers could be more likely in this century than had been estimated in the latest international review of climate research released in February.

b.    The largest area of sea ice can be seen in September.

• FALSE: the maximum and minimum area of Arctic sea ice, which typically expands most in March and shrinks most in September.

c.    Since the fifties, the area of sea ice is decreasing at a rate of more than 7% every ten years.

• TRUE: Dr. Stroeve found that since 1953 the area of sea ice in September has declined at an average rate of 7.8 per cent per decade.

III. Find a synonym for each of the four words below from these six options:

       shrink    released    huge    reviewed    trends    simulations

• a.    made public  released
• b.    tendencies  trends
• c.    examined  reviewed
• d.    diminish  shrink

IV. Choose a, b, or c, in each question below. Only one choice is correct 

1.  Human-generated gases produce...

• a)   ice on the Arctic Ocean in summer.
• b)  the melting of sea ice during the summer.
• c)  small changes during the summer.

2.  If carbon dioxide is not reduced...

• a)  floating ice will produce heat-trapping gases.
• b)  floating ice will disappear before 2050.
• c)  floating ice will disappear just after 2050.

3.  The author of this study examined...

• a)  data collected over a period of sixty years.
• b)  data collected by the scientist herself over a period of sixty years.
• c)  data collected for nearly sixty years.

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