Published online 6 January 2009 | Nature | doi:10.1038/457134a

News

Kunlun station to open later this month atop the frozen continent's oldest ice.

A base at Antarctica’s Dome A could provide access to the oldest ice-core samples yet. CAA

After a three-week crawl carrying 625 tonnes of cargo towards the highest ice in Antarctica, a Chinese expedition is expected this week to begin building a research base at Dome Argus, or 'Dome A', 4,093 metres above sea level. The station, called Kunlun and scheduled to open on 28 January, will gather data in fields ranging from global climate change to the origin of the Universe.

The 250-million-renminbi (US$37-million) Kunlun will be China's third Antarctic station, joining the Great Wall station in the South Shetland Islands and the Zhongshan station in east Antarctica. "The Kunlun station will be a major legacy of the International Polar Year and will propel China to the heart of the Antarctic map," says Jean de Pomereu, a photographer who followed the expedition to Zhongshan for the Brussels-based International Polar Foundation. "It is absolutely fantastic to have a station there," adds Eric Wolff, an ice-core specialist at the British Antarctic Survey in Cambridge, UK.

On 20 October, the Chinese Arctic and Antarctic Administration (CAA) sent its expedition team from Shanghai aboard the icebreaker Xue Long ('Snow Dragon' in English) to the coastal Zhongshan station. Bad ice conditions delayed their arrival, but on 18 December — two weeks behind schedule — a 28-man 'inland team' began the nearly 1,300-kilometre traverse to Dome A. On arriving at Dome A this week, the expeditioners will have just 20 days to build the station before temperatures drop sharply to below –50 °C in early February.

At the end of this year's first phase of construction, Kunlun is expected to have a main building of 230 square metres, with 11 units for sleeping, eating and working. It will have space for up to 25 people, says Qu Tanzhou, director of the CAA. Six more units are expected to be added next year, for a total area of 327 square metres.

Over the next decade, China hopes to add more facilities to Kunlun, including a large fuel tank and a solar-panel array to provide additional power, and to eventually be able to operate year round. The CAA also plans to have its own aircraft in Antarctica to shuttle researchers between Zhongshan and Kunlun, increasing the research capacity at both stations. "Only with these logistics in place will we be able to make the most out of the station," says Qu.

Source: P. Huybrechts, Vrije Universiteit Brussel

A key focus of research is finding sites where ice cores stretching back further in time than any others could be drilled. A core obtained at a site known as Dome C — about 1,000 kilometres from Dome A (see map) — reached 3,200 metres deep and helped to reconstruct past climate going back 800,000 years. Many believe that Dome A promises older ice because it is higher and has less snow, meaning that researchers can get more years of climate records in a given thickness of ice.

"Our radar studies show that the ice underneath Dome A is over 3,000 metres thick," says Sun Bo, a glaciologist at the Polar Research Institute of China, based in Shanghai. "This could push the climate record back to 1.5 million years."

What ice-core researchers have to decide first is where exactly to place their drills. "Ideally, the ice has to be deep and unfolded and not melting at the bottom," says Sun. To locate such ice, they are looking for help from Antarctica's Gamburtsev Province Project, an international initiative that is collecting data over a vast area of east Antarctica, including the buried Gamburtsev mountain range.

For the past several weeks, low-flying aircraft have been sweeping over the area, gathering gravity and magnetic readings as well as radar information to illuminate the thickness and internal layers of the ice sheet. The group has made at least seven data flights over Dome A, which will be fed into ice models to predict the best places to drill a core. Meanwhile, the Polar Research Institute of China will continue to gather data from the ground and will start test-drilling as early as next year.

Until then, researchers are pursuing other work they can do at Dome A: astronomical observing. "The seeing conditions on Dome A are just phenomenal," says Cui Xiangqun, director of the Nanjing Institute of Astronomical Optics & Technology. Last year the Chinese team installed a remotely operated observatory called PLATO built by the University of New South Wales in Sydney, Australia. Two of its four 14.5-centimetre optical telescopes broke down halfway through the winter, whereas the other two operated for more than 130 days before the last engine gave out. Early results from another PLATO telescope suggest that Dome A is an excellent spot to observe at sub-millimetre wavelengths.

Gong Xuefei, of the Nanjing institute, will repair parts of PLATO and calibrate its instruments this month — as well as adding an instrument to measure the transparency of the sky.