In the Antarctic, remarkable data on past atmospheric, oceanic, and terrestrial conditions are locked up, layer upon layer, in the Antarctic ice and in marine and lake sediments. By drilling into these different types of deposit and analysing many different clues, scientists are able to reconstruct how different parts of the Earth’s system have operated in the past and therefore gain a fuller picture of the origins and evolution of the Earth.
To do this effectively requires a network of sites spread across the Earth’s surface with many nations taking part. This is because different parts of the earth respond in different ways to climate changes such as global warming; some areas get hotter, whilst others cool down. For example, some scientists have predicted that the UK might actually cool down due to a weakening of the Gulf Stream that brings warm water to our shores. Within this network of sites, BAS has chosen to work in the Antarctic Peninsula and Weddell Sea regions and have already drilled a 1km long ice core from Berkner Island. The next phase is to collect marine sediment cores supported by the BAS ship James Clark Ross and lake sediment cores supported by HMS Endurance.
Doing geology in Antarctica is no easy task as 99% of it is covered by ice and, although the remaining 1% still presents considerable scope for research, actually getting to the exposed rocks can be a major problem. Some outcrops can only be reached from the sea or by helicopter.
Photograph courtesy of the
British Antarctic Survey
BAS has a long and distinguished history of scientific studies with HMS Endurance. Specifically the ship, its captain and crew have increased not only our capacity for science but also our capability; with helicopter support enabling us to visit sites that otherwise would be beyond our reach.
This season a team of scientists (Dominic Hodgson, Steve Roberts, Elie Verleyen and Wim Vyverman) and a mountaineer (Andy Lole) are visiting some of the small islands in the Southern Ocean and the Weddell Sea. Here they will be put ashore to set up camp, construct a raft and then drill into lake sediments. These sediments will then be analysed in the lab to build up a picture of the long-term climate changes in this region. As lakes are relatively rare in the Antarctic, these records form a vital part of the global network of sites that will be used to reconstruct past climates and enable us to better-understand how the Earth works.
In HMS Endurance work period 1 the scientists will visit Annenkov Island (near South Georgia). In work period 2 the ship travels to Prince Gustav Channel (east of the Antarctic Peninsula) to deploy scientists at View Point, Long Island and Beak Island. Finally in work period 3 the scientists will visit a small number of lakes in Marguerite Bay.
HMS Endurance is playing a vital role in supporting this project over the next few years by enabling further lake coring west of the Antarctic Peninsula (2006/7) and ice coring on James Ross Island (2007/8).
Collecting Ice Cores, Photograph courtesy of the British Antarctic Survey
This image shows a lake (centre) on Pourquoi-Pas Island situated at 21 m above the present sea level. With HMS Endurance support in 2003 scientists now know (by studying sediment cores) that this lake was inundated by the sea 6500 years ago and that the relative sea level was 41 m higher than today in this region about 9000 years ago. These, and similar data, are enabling computer modellers to simulate how much, and how fast, sea levels will rise in the future.
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British Antarctic Survey