[Scientists
said Wednesday that the Arctic has become a prime example of the built-in conservatism of
their climate forecasts. As dire as their warnings about the long-term consequences of
heat-trapping emissions have been, many of them fear they may still be
underestimating the speed and severity of the impending changes.]
By Justin
Gillis
A view of the east coast of
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The apparent low point for 2012 was reached Sunday,
according to the National Snow and Ice Data
Center, which said that sea ice that day covered about 1.32 million
square miles, or 24 percent, of the surface of the Arctic Ocean .
The previous low, set in 2007, was 29 percent.
When satellite tracking began in the late 1970s, sea ice at
its lowest point in the summer typically covered about half the Arctic Ocean ,
but it has been declining in fits and starts over the decades.
“The Arctic is the earth’s air-conditioner,” said Walt Meier,
a research scientist at the snow and ice center, an agency sponsored by the
government. “We’re losing that. It’s not just that polar bears might go
extinct, or that native communities might have to adapt, which we’re already
seeing — there are larger climate effects.”
His agency waited a few days before announcing the low to
be sure sea ice had started to refreeze, as it usually does at this time of
year, when winter closes in rapidly in the high Arctic . A
shell of ice will cover much of the Arctic
Ocean in coming months, but it is
likely to be thin and prone to melting when summer returns.
Scientists consider the rapid warming of the region to be a
consequence of the human release of greenhouse gases, and they see the melting
as an early warning of big changes to come in the rest of the world.
Some of them also think the collapse of Arctic sea ice has
already started to alter
atmospheric patterns in
the Northern Hemisphere, contributing to greater extremes of weather in the United States and other countries, but that case is not considered
proven.
The sea ice is declining much faster than had been
predicted in the last big United Nations report on the state of the climate, published
in 2007. The most sophisticated computer analyses for that report suggested
that the ice would not disappear before the middle of this century, if then.
Now, some scientists think the Arctic Ocean
could be largely free of summer ice as soon as 2020. But governments have not
responded to the change with any greater urgency about limiting greenhouse
emissions. To the contrary, their main response has been to plan for exploitation of newly accessible minerals in the Arctic ,
including drilling for more oil.
Scientists said Wednesday that the Arctic has
become a prime example of the built-in conservatism of their climate forecasts.
As dire as their warnings about the long-term consequences of
heat-trapping emissions have been, many of them fear they may still be
underestimating the speed and severity of the impending changes.
In a panel discussion on Wednesday in New York sponsored by Greenpeace, the environmental group, James E. Hansen, a prominent NASA climate
scientist, said the Arctic melting should serve as a warning to the public of
the risks that society is running by failing to limit emissions.
“The scientific community realizes that we have a planetary
emergency,” Dr. Hansen said. “It’s hard for the public to recognize this
because they stick their head out the window and don’t see that much going on.”
ASA, via Reuters
A NASA image shows how the record-low Arctic sea ice extent
compares with the average minimum extent over
the past 30 years, in yellow.
|
A prime concern is the potential for a large rise in the
level of the world’s oceans. The decline of Arctic sea ice does not contribute
directly to that problem, since the ice is already floating and therefore
displacing its weight in water.
But the disappearance of summer ice cover replaces a white,
reflective surface with a much darker ocean surface, allowing the region to
trap more of the sun’s heat, which in turn melts more ice. The extra heat in
the ocean appears to be contributing to an accelerating melt of the nearby Greenland ice
sheet, which does contribute to the rise in sea level.
At one point this summer, surface melt was occurring across 97 percent of the
Greenland ice sheet, a development not seen before in the era of
satellite measurements, although geological research suggests that it has
happened in the past.
The sea is now rising at a rate of about a foot per
century, but scientists like Dr. Hansen expect this rate to increase as the
planet warms, putting coastal settlements at risk.
A scientist at the snow and ice center, Julienne C. Stroeve, took a ride on a
Greenpeace ship recently to inspect the Arctic Ocean
for herself. Interviewed this week after pulling into port at the island of
Spitsbergen, she said one of her goals had been to debark on ice floes and
measure them, but that it had been difficult to find any large enough to
support her weight.
Ice floes were numerous in spots, she said, but “when we
got further into the ice pack, there were just large expanses of open water.”
NEW CRACKS ARE FORMING INCOALITION LEADING INDIA
[After the
announcement by Mamata Banerjee, the populist chief minister of
the state of West Bengal, that her party would formally leave the government on Friday, another member of the
government, Muthuvel Karunanidhi, said his party would support a nationwide
strike on Thursday called by opposition parties to protest economic policy
changes announced last week by the governing coalition, the United Progressive
Alliance. Mr. Karunanidhi controls 18 votes in Parliament, just one fewer than
the total controlled by Ms. Banerjee.]
By Jim Yardley And Gardiner Harris
After the announcement by Mamata Banerjee, the populist chief minister of
the state of West Bengal, that her party would formally leave the government on Friday, another member of the
government, Muthuvel Karunanidhi, said his party would support a nationwide
strike on Thursday called by opposition parties to protest economic policy
changes announced last week by the governing coalition, the United Progressive
Alliance. Mr. Karunanidhi controls 18 votes in Parliament, just one fewer than
the total controlled by Ms. Banerjee.
Meanwhile, Ram Gopal Yadav, a major leader of the Samajwadi
Party, which controls 22 votes in Parliament, said his continued support of the
governing coalition was no longer assured. “This government has lost
credibility and can’t take our support for granted,” he said, according to news
media reports.
Ms. Banerjee has given the government has until Friday to
reverse new economic measures, including those that would allow multinational
giants like Walmart and Ikea to build major retail outlets in India, or else
her 19 lawmakers will withdraw from the coalition. Since Parliament is not in
session, there is little risk that the government would collapse immediately.
But if Ms. Banerjee follows through on her threat, the governing coalition must
rely on Mr. Karunanidhi, Mr. Yadav and others to avoid early elections.
The battle of words between the national government and Ms.
Banerjee intensified Wednesday as Kunal Ghosh, a member of Parliament from Ms.
Banerjee’s party, demanded that Prime Minister Manmohan Singh seek a new electoral mandate,
suggesting he should resign. Each side in the dispute between Ms. Banerjee and
the government insisted in interviews that the other had rejected overtures for
discussions in recent days.
Ms. Banerjee, in a fiery address on Tuesday night, accused
the government of “selling the country” as a result of the policy changes it
announced last week, which raised the price of diesel fuel and allowed greater
foreign investment in retailing and aviation. Ms. Banerjee contends that these
steps will hurt the poor and destroy small retailers, though many economists
and business leaders say the measures are critical to attracting investment, helping
address the country’s fiscal deficit, and, over the longer run, reviving growth
in the faltering Indian economy.
Hari Kumar contributed reporting.