Finding and Mapping Subglacial Lakes
So, how do we know that these lakes are there? Through the early stages of Antarctic exploration they remained unknown. As scientific techniques have developed in the last four decades, however, methods such as echo sounding and satellite imaging have recorded minute changes in the shape of the surface ice, revealing anomalies and indicating the presence of liquid water beneath the ice sheet.
More detailed exploration using on-the-ground techniques such as seismic imaging (using small explosions to record reflections on the surface of the ice and measuring the time taken for the seismic waves which they generate to rebound) have been used to look in closer detail at lakes such as Lake Vostok and Lake Ellsworth, giving more information on the shape of the lakes.
Exploration of Sub-glacial Lakes: Why Bother?
Exploring these distant and previously inaccessible bodies of water is challenging, expensive, and time-consuming. But, scientists persist, and there are major high-profile scientific projects currently under way to reach and explore such lakes as Lake Ellsworth and Lake Whillans in West Antarctica and Lake Vostok in the east of the continent.
Edinburgh University’s Dr. Neil Ross, a member of the combined scientific expedition to explore Lake Ellsworth, the study of subglacial lakes is important both for biological and geoscientific reasons. On Earth, water supports life: and in water which has been isolated for many thousands of years, there is much to be learned from the life forms – almost certainly only at microbial level – expected to be found there.
Dr. Ross also told Decoded Science that such research will help scientists understand more about the workings and the dynamics of the ice sheets. Recent studies have indicated, for example, that many lakes are linked and that water flows between them – a fact which has implications for the movement of glaciers which flow from the ice cap.