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Written in the ice

Written in the ice in an effort to gather data regarding temperature, wind flow and other climatic factors in the Arctic Ocean and to minimise the ambiguity in global climate forecasting, a us $19.5-million study is being carried out in the Arctic. The project, known as Sheba (short for Surface Heat Budget of the Arctic Ocean), is by far the most expensive and complex research programme financed by the National Science Foundation of the us in the Arctic. The project is also supported by the us Office of Naval Research and the Japanese government, among others.

Under the project, a heavy icebreaker of the Canadian Coast Guard has been chartered to be frozen into a drifting floe (a detached portion of an ice-field) in the Arctic Ocean. On the icebreaker, the project's 50 scientists from five countries will make numerous measurements in extreme climatic conditions for the period of one year. The data, they hope, would quell the disagreements among scientists regarding the importance of the Arctic in global climatic behaviour. This would be especially important to our understanding of the greenhouse effect.

One theory of greenhouse effect has it that a doubling of the amount of carbon dioxide in the atmosphere in the next century could cause global warming, leading to the melting down of Arctic sea ice that covers an area the size of the us . This, the theory contends, could have grave consequences for the Earth. It is feared that the sea level will rise, submerging a lot of low-lying areas of the world.

On the other hand, another theory put up by climatologists has it that the effect of increased carbon dioxide would be less severe. The answer to this debate lies in accurate compilation of data and its detailed analysis. "Only by measuring fine details of the complex climate engine will it be possible to assess and perhaps resolve such broad questions,' said Richard E Moritz of University of Washington, who is the director of project Sheba. This is the first time since 1893 that a research ship is being frozen in the Arctic ice. In 1893, the great Norwegian explorer and scientists Fridtjof Nansen froze his wooden ship Fram in the Arctic ice to make scientific observations.

An important advantage of the data from Sheba would be the ability to make better use of satellite pictures of polar seas. At present, these pictures cannot clearly distinguish cloud cover from surface ice. This inhibits correct interpretation as clouds and sea ice have very different roles in shaping the climate. Data from Sheba would be compared with satellite photographs to get a better picture of the Arctic climate.

The position of Sheba in the Arctic was chosen to include representative samples of thick pack ice, melted surface ponds, open water in cracks (known as leads), many types of snow cover and all possible cloud conditions. The researchers will deploy thousands of sensors within the ice column, in the water, in the surface ice and in the air, mounted on towers and balloons.

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