WISSARD Project Overview

Subglacial Antarctic Lakes

Subglacial Aquatic Environments

Over the last several decades, by using ground penetrating radar and other remote sensing tools, scientists have discovered that under the massive Antarctic ice sheets there lies a vast hydrological system of liquid water.  This water exists because geothermal heat flow from below, coupled with pressure, movement, and the insulating nature of the ice sheet above, is great enough to maintain some areas at the base of the ice sheet above the freezing point, even in the extreme cold of Antarctica.  In topographic depressions there are hundreds of lakes, both large and small; some are isolated, but many are interconnected by water channels and large areas of saturated sediments, the water eventually running out into the Southern Ocean as the ice sheet becomes a floating ice shelf.

WISSARD

In order to explore one of these hydrological systems at the margin of the West Antarctic Ice Sheet, we have organized an interdisciplinary project to access the subglacial environment.  The Whillans Ice Stream Subglacial Access Research Drilling project (WISSARD) is using a variety of tools and techniques to explore Subglacial Lake Whillans and the nearby grounding zone, on the southeastern edge of the Ross Sea.  Radar and seismic equipment is used to profile the overlying ice sheet and the underlying water, sediments, and rock, while GPS stations accurately track ice movement.

This season our target is the grounding zone, where the massive West Antarctic Ice Sheet atop land meets the Ross Sea. This area is considered an important piece of the puzzle for our scientists interested in ice sheet dynamics. The work will help scientists assess the stability of the West Antarctic Ice Sheet, most of which sits below sea level. It is the last ice sheet on Earth resting in a deep marine basin and is the most likely player in any future, rapid sea-level rise. If the grounding zone is retreating or primed to retreat, rapid changes in ice behavior could follow over the next century. Work focused on microbial life, biogeochemical cycling, and surrounding geophysical surveys will also continue during the 2014-2015 season.

Our intentions are to have 8 days of science in the primary borehole at the Grounding Zone location mid-January. We will deploy all of the WISSARD tools during this period and recover sediment and water samples from the water cavity some 750 meters below the surface of the ice. We also hope to recover about 5 meters of basal ice cores at another borehole very near the primary hole. Image: Rachel Xidis/NIU.