IPY 2007-2008

Fleming Glacier Filedworks

First Year Fieldwork (2007)

In November-December 2007, CECS conducted the first field campaign with airborne support and installed scientific equipment that will operate permanently and autonomously.
 
The glacier was accessed by aircraft after waiting for flyable weather in Rothera. The expedition team established a camp in the glacier (69º32'S, 66º01'W, 1386 m asl) from which they started by foot to explore the area to conduct various measurements. They installed an Automatic Weather Station (Campbell Scientific) with a suite of sensor including radiometer, thermometer, anemometer and barometer to determine the principle components of the energetic balance of the glacier.


The antenna of thecontinuous GPS station was mounted on top of the AWS tower. In addition, a geodetic network was installed including sites with previous measurements to measure ice flow velocities. All GPS measurements were done using double-frequency GPS receivers (Javad Lexon GD).

These ice flow velocities allow to analyze the dynamics of the ice and to compare them to earlier velocity estimates of this area. Two stakes were set up at locations with reference values for velocities (Doake, 1975) to study changes in ice flux during the last 34 years.

Next to the stakes radar measurements were realized to determine the internal structure (30m) of the glacier and the snow accumulation of recent years using a GPR (Geophysical Survey Systems SIR-3000) with a central frequency of 400 MHz. Additionally, snow densities were measured using a Mt. Rose Snow Sampling Tube.

Preliminary Results

The radar and density data allowed to estimate changes in the snow accumulation in the last years with values between 0.8m water equivalent (w.e.) for the last accumulation period (2007) and 1.9m w.e. in 2004 indicating to a possible decrease in mass balance. It is worth mentioning that Fleming Glacier presents evidence of a complex dynamics, since during the overflights from Rothera to the camp on the glacier a large quantity of crevasses, faults and folds could be observed indicating to probable changes in ice flux. The results to be obtained from the geodetic and meteorological measurements will allow of determining how the glacier responds to the climatic conditions in the area of Antarctica.