Polar ice is melting … Is this true?

02.11.2012

But if the ice melts, really? This phenomenon was widely covered, as well as many others related to global warming, caused by the attacks of so-called climate skeptics, and get to the bottom of what is really going on with the ice caps are not very easy.

Drifting ice in the Arctic Ocean. Among the skeptics and scientists are heated arguments about the melting or growing ice. Photo courtesy of NOAA News

Steve Goreham, executive director of the American Coalition for Climate, recently wrote an article in response to the transmission of the news Pee-PBS (Public Broadcasting Service) from 20 September to reduce the Arctic ice cap.

Author of the book "It's a Mad, Mad World klimatizma: the human mania and climate change," Goreham accused Pee-PBS is that they ignore the obvious facts.

He explained that the Arctic ice cap actually melt, but they make up only about 2% of global ice, while 90% of the ice is in the Antarctic ice cap, which, according to the National Snow and Ice Data Center, increases.


Does this mean that all is well with the polar ice?

Professor Veigy Pohzhola, a glaciologist at the University of Uppsala in Sweden, said: "The main facts in the article are correct, but, as always, when you're dealing with a self-taught (Goreham — not an expert in this area), there are mistakes." Pohzhola explained that the sea ice — ice drifting in the ocean and ice sheet and glaciers on land live fully independent lives.

The state and the amount of sea ice varies greatly depending on the season, while the ice sheets and glaciers are changing very slowly. It is true that the Antarctic ice sheet contains most of the world's ice, but it is on the continent and the Arctic ice — sea ice completely.

In the Antarctic, is also a part of the sea ice volume has increased slightly over the last 30 years, about 1%.

Over the same period, the volume of Arctic sea ice decreased by 4%. It may seem that the difference is small, but it is essential.

"The statement that in ten years in the Arctic will not be ice in the summer season, you can not even be considered pessimistic," — said Pohzhola.

In academic circles, the controversy is over the question whether the increase in Antarctic ice strategic importance. Goreham said yes, and Pohzhola agree with him on this matter, but believes that additional research is required to understand why this is happening.

In any case, says Pohzhola, current climate models predict that the Arctic global warming will manifest more quickly and clearly.

The reason is that such ocean currents as the Gulf Stream, like hot water path, which extends from the equator to the Arctic, while the Antarctic ocean currents around a different nature, and there occurs such a large heat transfer.

As the ice breaks off Greenland

So forget for a moment the fate of polar bears, if the majority of the world's ice in the ice sheets, and the Antarctic ice sheet is actually growing, does not this mean that there is no danger that the world will be under water by the melting of the polar ice caps?

Pohzhola says that the reality is much more complicated.

"85% of the world's glacial ice is in Antarctica, but the remaining 15% is sufficient to raise sea levels by 7-8 meters, so I believe that the public should know about it," — said Pohzhola.

Most of these 15% are located on the island of Greenland in the Arctic, where in the past few years there are dramatic events — large chunks of ice break off and are carried to the ocean.

It considers Pohzhola may be due to the fact that the ice sheet eroded by the increased temperature of the water from the bottom of the ocean.

Moreover, this phenomenon is also observed in West Antarctica.

Ice sheet in East Antarctica has risen slightly due to increased precipitation, which is also a result of global warming. However, the western part, as shown by gravimetric studies, has lost six times more mass. However, it is very difficult to measure, said Pohzhola.
Goreham meanwhile believes that to Greenland is "different conclusions", but he is skeptical about the gravimetric studies.

"Gravimetric measurements from the NASA GRACE satellites showed large errors and have given nothing, no doubt, — he said. — In addition, researchers have gravimetric data just a few years. These data are subject to short-term fluctuations and can not assess what was happening in Greenland or Antarctica for decades. "

Growing all the ice or decreasing?

Goreham said that the ice in Greenland "melts only at the edges due to the natural warming of the Earth after the Little Ice Age, but in the center of the ice cover becomes thicker due to rise of the snow."

He cites as an example a group of planes left in Greenland in 1942, which were found under the 270 foot layer of ice.

"This reflects a lack of understanding of the dynamics of the ice — said Pohzhola. — Even if the ice sheet is losing mass, the upper part of it will always accumulate mass, while the ice is moving down to the outlet to the ocean. This means that Greenland can lose an incredible mass of ice, but the aircraft will go down and buried in snow, "- he said.

This skirmish between skeptics and those who can say, is the dominant trend in science and who was nicknamed "klimatistami" layman's reserves are at a loss.

Pohzhola believes that, as a scientist, he should try as clearly as possible to present complex scientific data, especially in such an important and controversial issue, such as global warming.

"This is the only way to win the trust of the public — said Pohzhola. — Extremists on both sides of the climate debate is rarely listen to scientific arguments. They take our cautious statements and uncertainty, as a sign that we really do not know. But they do not understand our way of reasoning. "

"You can sum up all the signs that we are celebrating today, by saying:" If someone walks like a duck and quacks like a duck, it probably is a duck "," — he added.

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