Extreme Environments

'There are over 145 lakes underneath the Antarctic ice sheet, with Lake Vostok being the largest, lying beneath 4km of ice.’

On 27th April a ‘fledgling’ Geographical Society was launched with what proved to be a fascinating lecture entitled ‘Extreme Environments:  Antarctic Subglacial lakes.’  The talk was presented by George Royston-Bishop from Bristol Glaciology Centre, University of Bristol.  The focus of Mr Royston-Bishop’s research over the last three years has been an examination of ice cores from Lake Vostok, the largest subglacial lake in Antarctica (over 145 have been recorded to date), measuring 260 km long and 80 km wide.  This lake is buried beneath almost 4 km of ice.  It is thought that Lake Vostok may have been isolated from Earth’s atmosphere for over 15 million years.

To a packed lecture room Mr Royston-Bishop identified the reasons behind current scientific interest in subglacial lakes and the possibility of discovering life in such a unique and extreme combination of permanent darkness, very high pressure and low temperature.

To date none of Antarctic’s subglacial lakes have been directly sampled, in order to minimise contamination of lake water.  Mr Royston-Bishop’s ice core samples were taken from ‘accreted ice’, this is lake water that has become frozen onto the bottom of the overlying ice sheet.  This ice was then analysed in order to examine its physical, chemical and biological condition.  The research findings have identified living bacterial life in the accreted ice, indicating that primitive life exists in subglacial lake environments.

Mr Royston-Bishop concluded by highlighting that his research is also of interest to space scientists who believe that a liquid water habitat deep below a frozen surface provides an analogue for possible life on icy planets and moons, such a Europa, one of Jupiter’s moons.

Further information on the work of the Bristol Glaciology Centre and their involvement in a new venture exploring Lake Ellsworth, a subglacial lake in West Antarctic, can be found at the following website: www.ggy.bris.ac.uk/ellsworth

Further Geographical Society talks are planned for 2006-2007 on topics ranging from global warming and natural hazards to development issues in the Gambia.

Mr N J MeekHead of Geography

Mr N Meek introduces the Lecture.

Bacteria identified in Lake Vostok ice cores

Mr Royston-Bishop, selecting ice cores