Sabtu, 17 September 2011

Arctic ice hits close to record low, threatening wildlife

16 September 2011

Audio for this story of morning Edition will be at approximately 9: 00 am ET available.

Ice on the Arctic Ocean has melted to its second-lowest level on record. Above, ice in a fjord in Greenland.Slim Allagui/AFP/Getty Images

Ice on the Arctic Ocean melted to the second lowest level on record. Ago, ice cream in a fjord in Greenland.

Ice on the Arctic Ocean melted to the second lowest level on record, according to researchers in Colorado, to pursue this development. The summer melt with a dramatic warming in the last ten years, and it is already the wildlife in the Arctic Ocean.

This year, the height of the Arctic sea ice met the second lowest level since records began in 1979. The table below shows the amount of Arctic ice, in million square miles, since 2007.

Chart showing amount of arctic sea ice, 2007-2011

The Arctic ice comes and goes with the seasons; Usually about half of the winter melts ice until mid-September. After this low point, the ice grow back. In 2007 the amount of ice hit a dramatic links in September low.

Says Mark Serreze, who leads the national snow and ice data center in Colorado, this year deep not far away is that 2007.

He says "what it tells us that the long term decline of Arctic sea ice being continued, and even seems at this time speed".

Says Serreze, what is to this year 2007 compared with the record-low year the weather was different.

"In 2007 one of the major reasons we to a record low, is, because we basically had a near-perfect weather pattern, pumped the many warm air in the Arctic," says Serreze.

Unusual cloud-free sky accelerated melting, and wind patterns of ice to disappear. Serreze says that was this year's melt almost as bad, but without the extreme weather.

Sea ice is really in trouble. The ice is so thin, now that it can take only a hit more in the summer.

-Mark Serreze, national snow and ice data center

", The US is the ice really in trouble, says", he says. "The ice is so thin, now, that it can take only a hit more in the summer."

This is a vicious circle set up. There is no question that the will freeze over Arctic Ocean up again in the autumn and winter, but there is less and less really thick ice building backup from year to year.

"Next spring come, are we only have a lot of thin ice, in autumn and winter." "This is the stuff that simply melts the next summer," says Serreze. "So there is a feedback at work, and this feedback is always stronger with time."

Serreze says the Arctic could be ice-free in the summer to about 2030, though, is that difficult to predict; other scientists say that it could be middle of the century, before this tragic point is reached.

Why is it important? Ice that is swimming at sea raise not sea level when it melts. But researchers believe that it the weather will change, when us far to the South. It is already affecting Arctic nature.

Thousands of walruses that float around on ice and to feed diving on the ocean floor as the only ice from the Coast Alaska links was abandoned, the ice floes of water, that was too deep.

"After the sea ice ran out, much the walruses came to the coast of northwestern Alaska and began dragging," says Chad Jay, an ecological research with the United States Geological Survey in Alaska. He says it to feed from coast, is more difficult on the walruses because they have to swim, to cut back on their food supply. It also says more dangerous for them to on the rocks instead of being on hold to it.

"When they out moved into these large aggregations on the Bank, if there is an error or something that causes the walruses to flee quickly in the water, then quickly lead the calves over and die as a result", says Jay.

He is now trying to find out how the walruses adapt, since continued, that the sea ice melt.



View the original article here



Peliculas Online

0 komentar:

Posting Komentar