Advances in modelling subglacial lakes and their interaction with the Antarctic ice sheet.

Subglacial lakes have long been considered hydraulically isolated water bodies underneath ice sheets. This view changed radically with the advent of repeat-pass satellite altimetry and the discovery of multiple lake discharges and water infill, associated with water transfer over distances of more than 200 km. The presence of subglacial lakes also influences ice dynamics, leading to glacier acceleration.

A decade of progress in observing and modelling Antarctic subglacial water systems.

In the decade since the discovery of active Antarctic subglacial water systems by detection of subtle surface displacements, much progress has been made in our understanding of these dynamic systems. Here, we present some of the key results of observations derived from ICESat laser altimetry, CryoSat-2 radar altimetry, Operation IceBridge airborne laser altimetry, satellite image differencing and ground-based continuous Global Positioning System (GPS) experiments deployed in hydrologically active regions. These observations provide us with an increased understanding of various lake systems in Antarctica: Whillans/Mercer Ice Streams, Crane Glacier, Recovery Ice Stream, Byrd Glacier and eastern Wilkes Land.

A microbial ecosystem beneath the West Antarctic ice sheet.

Liquid water has been known to occur beneath the Antarctic ice sheet for more than 40 years, but only recently have these subglacial aqueous environments been recognized as microbial ecosystems that may influence biogeochemical transformations on a global scale. Here we present the first geomicrobiological description of water and surficial sediments obtained from direct sampling of a subglacial Antarctic lake. Subglacial Lake Whillans (SLW) lies beneath approximately 800 m of ice on the lower portion of the Whillans Ice Stream (WIS) in West Antarctica and is part of an extensive and evolving subglacial drainage network.