Life Beneath the Ice Caps

American Geophysical Union, Fall Meeting 2007

Pivotal studies of polar ice caps reveal an intricate subglacial lake system that moves large volumes of water beneath the Antarctic ice sheet. Research conducted by scientists at Scripps Institution of Oceanography at UC San Diego provides new insight into the previously unidentified processes occurring under the Antarctic ice sheet and its potential to harbor unique life forms.

Scripps Oceanography Research Professor Helen Amanda Fricker will discuss details of her research, titled "Subglacial Plumbing Mapped from Space: Water Transfer, Water Volumes and Implications for Ice Dynamics" during an invited talk at the 2007 American Geophysical Union Fall Meeting.

Fricker and her research team analyzed satellite data to document the long-distance movement of subglacial waters that occurs under the fast-flowing ice streams to the grounding line, where the waters reach the Southern Ocean. This research reveals new evidence of subglacial lakes draining into each other and their role in initiating fast ice stream flow in the upper glacier catchments, where the water collects in the natural drainage system.

"Understanding Antarctica's complex subglacial plumbing is of critical importance to monitor the entire ice sheet system and its potential for change," said Fricker.

The Antarctic ice sheet is one of only two polar ice caps on Earth. Ice streams are components of the ice sheet that move faster than surrounding ice and may be up to 50 kilometers (31 miles) wide and 2 kilometers (1.25 miles) thick, stretching for hundreds of kilometers. The ice streams are responsible for transporting most of the ice leaving the continent to the floating ice shelves and, ultimately, to the ocean.

Monitoring subglacial outflows from the ice sheet margins is also important for quantifying the freshwater input to the ocean and understanding ice-ocean interactions. Discovery of lakes close to the grounding line, where there are no downstream lakes, provides an opportunity for exploration without the risk of contaminating other lakes.