While East Antarctica is fascinating place and anybody who knows me probably hasn’t even stopped to question why I’m here, I thought I should probably elaborate. The work is part of a project, now in it’s third year, head up by Dr Christian Schoof, ‘Outlet Glacier Dynamics on Princess Elizabeth Land’. Here’s the official line…..
The edges of the world’s big ice sheets in Antarctica and Greenland hold the key to future sea level rise. Mass can be lost rapidly from these ice masses through icebergs breaking off, or through ice flowing into the ocean faster. Research over the last decade has shown that rapid changes in West Antarctica and Greenland can be driven by a number of physical processes that act to accelerate ice flow and iceberg formation. Much less is known about how the same processes affect ice dynamics in East Antarctica. This project will make detailed observations, at an outlet glacier draining a part of the East Antarctic Ice Sheet, of ice flow response to the formation of surface meltwater, changes in sea ice conditions and rifting/calving and melting at the ice-ocean contact. Understanding how these processes affect the flow of ice will help to improve computational models of ice sheets, and therefore projections of future sea level rise.
What is means is that for the next couple of months we are going to focus on the Sørsdal Glacier, located in Princess Elizabeth Land, East Antarctica, close to the Australian Station Davis. It’s a small outlet glacier by Antarctic standards but when we flew over it, it seemed huge. A project investigating glacier dynamics has been running for a few years now and it was observed that every austral summer the Sørsdal Glacier experiences melt resulting in the formation and later drainage/freezing of a number of large ponds. In Greenland the flow of the ice sheet speeds up every summer in areas where there is enough melting at the surface to cause water to pond. The ponds often drain down through the ice until the water reaches bedrock. There, the water acts as a lubricant, causing the ice flow to speed up. We know very little about the effect of surface ponds on the flow of ice in East Antarctica. This part of the project is focusing on monitoring surface runoff and investigating the effect on ice flow dynamics. It will help to determine how ice-ocean interactions including basal melting under ice tongues and changing sea ice conditions affect ice flow and to provide a baseline for possible longer-term observation.
We’re focusing on three different lake systems, Horseshoe Lake, Channel Lake and Twin Lakes. Each of the lakes has a different size and shape and the drainage mechanisms seem to be variable.This season we are adding to a number of existing data sets and instruments already on the glacier, to investigate the formation of melt ponds and determine how and where the melt water drains from the ponds through the ice the we plan to
- deploy seismometers, to detect the micro tremors created by the water flow in the ice
- conduct airborne ice-penetrating radar measurements using the station helicopter, to detect and delineate the drainage pathways in the ice
- deploy self potential electrodes to identify the flow of water within the ice
- conduct an experiment by which a salt tracer is dissolved in the pond waters and then tracked by water sampling and radar measurements down flow of the lake.
- install a suit of meteorology sensors close to one of the lakes, providing a full energy balance and near surface ice temperature profile.