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Old, cold water and hot air

十月 16, 1998

Andrei Kapitsa, who discovered a vast new watery world under the ice of Antarctica, says people are not to blame for global warming. Julia Hinde reports

It was Andrei Kapitsa, a Russian geographer, who discovered a vast lake isolated from the world for a million years beneath the Antarctic ice. Lake Vostok, for which scientists are still digging, promises to yield undreamt of life-forms and spawn a thousand new avenues of research. Yet the man who found it is in England looking for an argument.

So far, he is disappointed by the response. For Kapitsa doubts that man's activities, particularly the burning of fossil fuels, can greatly affect global temperature or ozone levels. "Global warming as a result of man's activities does not exist," he told a London conference earlier this year. "People who say it does have predicted temperatures would get higher for the past 20 years, but globally this has not happened."

Likewise, environmentalists' claims that the Antarctic ice sheet is shrinking are "absolute nonsense", Kapitsa says. He argues that it is environmental activists, not scientists, who have spread such ideas. "It's to do with politics," he says. "It's very popular now to say we are fighting for the environment, saving the world."

Kapitsa has spent the past three decades monitoring environmental change, first leading 7,000 scientists at the National Academy of Science in Vladivostok in Siberia, and later at Moscow State University, where he is professor of geography. He also has a house in Cambridge that was designed and built in 1939 by his father, Nobel-prize winning physicist Pyotr Kapitsa.

"I gave a lecture in Cambridge a couple of years ago on the myths of global warming and of the ozone hole, but not one of my opponents would come and discuss the issue with me," he says. "It is disappointing, but the facts are against them. I am for discussion not dictatorship in the academic world."

It is for his discovery of Lake Vostok, which could become one of the biggest scientific challenges of the early 21st century, that Kapitsa is best known. He was part of the first Soviet scientific expedition to Antarctica in 1955. "The first day we reached Antarctica we could not see it because it was so big. We thought the ice in front of us - several hundred metres high - was the sky. Only later did we understand how enormous it was. But it was also so pretty. Snow in sunlight yields wonderful colours."

From the expedition's station, Kapitsa and his colleagues worked in teams taking seismic measurements to calculate the thickness of the ice. Previous glaciological work had suggested that ice could not lie deeper than a couple of thousand metres. Ice at a certain depth would melt from the heat from the earth's crust below and the pressure from the ice above. Recording the time taken for reflected seismic waves created by detonating explosives to reach the surface, Kapitsa estimated that Antarctic ice was up to 4km deep - deep enough to harbour fresh water.

His team also observed how icebergs seemed to be made of two sorts of ice: glacial ice formed from snow accumulating at the top, and freshwater ice from frozen water at the base. "We found by flying over the ice cap of central Antarctica that parts were flat, not domed," explains Kapitsa, who mentioned the possibilities of a sub-glacial lake in his thesis as early as 1957. But it was only in the mid-1990s that the importance of his work was revealed.

Kapitsa was invited by the Scott Polar Research Institute in Cambridge to join a symposium on Antarctica. The British scientists had been studying airborne echo-soundings of the Vostok area and were getting mystifying readings. Kapitsa returned to his 1960s data, and what he saw proved invaluable. When seismic waves travel through water, longitudinal waves are reflected back, but latitudinal ones are not. Kapitsa's data showed no reflected latitudinal waves, proving the presence of water in the ice.

Together, the Scott Polar team and Kapitsa wrote a paper, published in Nature in 1996, estimating Lake Vostok to be the size of Lake Ontario, some 500 metres deep, buried beneath 3,500 metres of ice. "In 1957 I could not have imaged the lake to be 500 metres deep," Kapitsa says. "We didn't really understand what we had found. I thought at the time that the lake was going to be 20 or 30 metres deep. That was my error. What I was seeing I thought must be sediment underneath the ice. It did not occur to me that the readings I was getting were really because of the lake."

Now scientists have bored to within 150 metres of the lake, which has been isolated for a million years. Excavation has stopped until scientists can find a way to enter the water without contaminating it with their instruments. Scientists from the United States space agency Nasa, which is keen to investigate Europa, Jupiter's ice-covered moon, have joined the British, Russian and French teams working on the project. What is proposed is a remote-controlled probe that will be able to melt the ice as it travels towards the water, with the ice then re-freezing above the probe. The probe will send information back to scientists via an umbilical cord. With water, heat and oxygen beneath the ice, there is every possibility of finding life, Kapitsa says.

Lake Vostok promises a whole new world again. "We think what we will find will be at the microbiological level," Kapitsa says, dispelling any hopes of finding monsters like Nessy. "But there is a possibility of plankton totally different to what we have seen before. This is an unknown part of the planet."

THE CASE FOR A NATURAL EVENT

Andrei Kapitsa is adamant that man's activities can have only a negligible effect on the earth's temperature, which is governed almost entirely, he believes, by solar and volcanic activity. His views differ from those of many scientists, who see an inextricable link between global warming and the carbon dioxide released by burning fossil fuels.

Kapitsa is not alone. After the Kyoto agreement on reducing emissions of greenhouse gases, thousands of United States scientists signed a petition saying there was "no convincing scientific evidence that human release of carbon dioxide, methane or other greenhouse gases is causing I catastrophic heating of the earth's atmosphere and disruption of the earth's climate".

Kapitsa believes it is time for more open academic debate on the subject. He argues that 90 per cent of the world's carbon is dissolved in the oceans. A 0.50 C rise in global temperature would warm the water, causing it to release dissolved carbon dioxide.

The historic climatic record, Kapitsa says, does link higher temperatures with a rise in carbon dioxide. But he says that it is the rise in temperature that releases the carbon, not the other way round. Despite an 80 per cent increase in the carbon dioxide in the atmosphere over the past 40 years, global temperatures have been stable, he says.

In fact, Kapitsa believes that more carbon, and therefore more photosynthesis and plant growth, could be a good thing: "If you are using less carbon fuel, you will have less harvest, and people could starve in the third world."

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