17 July, 2012

Scientists take part in BBC expedition “Operation Iceberg”

This summer two British Antarctic Survey (BAS) scientists head to the Arctic to take part in the BBC expedition ‘Operation Iceberg’. Oceanographers Dr Keith Nicholls and Dr Povl Abrahamsen will join the BBC team on the ice near Baffin Island as they make a two-part series for BBC2.

The programmes will explore ice and how it behaves, both as a glacier flowing toward the sea, and then after it breaks off into an iceberg. The filming team will interview the BAS scientists for programme two which is based on and around an iceberg as they conduct experiments to better understand how it interacts with the ocean beneath.

Dr Nicholls and Dr Abrahamsen will take part in two studies whilst they camp out on in tents on the iceberg. The first will be to drill a hole through 80 metres of ice using a technique called hot water drilling, frequently used in Antarctica. Once the hole is drilled, a probe will be deployed down a wire to measure the temperatures and salinities in the sea beneath the iceberg. The results will show them how the oceanographic conditions control the rate the iceberg is melting from below. Together with the other groups’ measurements this can help estimate how long the iceberg will last before it finally drifts southward and melts into the sea.  A second study will involve drilling a shallow ice core (up to 20 metres long) to measure the temperatures in the interior of the iceberg, and retrieve samples that will be melted and sent back to Cambridge for analysis. The results will give insights into the climate conditions when the iceberg originally was formed on Petermann Glacier in northwest Greenland. Finally, they will set up an accurate downward-pointing radar system that will give a measurement of how much the iceberg melts during the period of the fieldwork.

The two-part series is presented by scientist Dr Helen Czerski (from the BBC series Orbit) and wildlife expert Chris Packham. The expedition is underway with its base on the vessel  MV Neptune and will be on the ice until mid-August. Operation Iceberg airs on BBC2 on 9th and 16th September. To find out more or to check out the latest updates from the expedition team visit: www.bbc.co.uk/operationiceberg

Dr Keith Nicholls trained as a physicist, and has worked at British Antarctic Survey since 1987. He helped to develop the techniques BAS had pioneered earlier in the 1980s, using a light-weight hot-water drill to make access holes through floating ice shelves a few hundred metres thick so that scientists could study the ocean beneath. Today he coordinates the oceanographic work undertaken by BAS over the continental shelf of Antarctica using a variety of tools, including ship-based oceanographic surveys, autonomous underwater vehicles, ice-shelf based studies, and computer-based modelling. The interaction between ice shelves and the ocean remains a prime focus because of the observation that thinning or loss of ice shelves results in faster flow of ice from the grounded ice sheet into the ocean, leading directly to a rise in sea level.

Dr Povl Abrahamsen is a physical oceanographer at the British Antarctic Survey. He has been studying a variety of subjects from the circulation beneath Antarctic ice shelves to the flow of freshwater in the Laptev and East Siberian seas. More recently he has been involved with deploying moored instruments to monitor the northward flow of the cold, dense bottom water that is formed around Antarctica.