When

We have organized our field activities into two seasons of intensive work preceded by an initial reconnaissance trip and a final visit to remove as much equipment as possible. Specific tasks scheduled for the various field seasons are:

2007-08:

Can we land safely on the PIG ice shelf? That’s the primary question to be answered in this reconnaissance field season. Next we will take care to define the size of a safe working area for subsequent field teams. Due to possible difficulties, we will carry a minimum of equipment and stay about 7-10 days. We will set up an automatic weather station, two web cams and two GPS units that will phone data back to us, hopefully for a full year, including through the dark, frigid winter. Other measurements will be made of the ice thickness, the water thickness, the snow conditions and its temperature. These data are crucial to determine the size of the drilling system, the amount of fuel needed to drill the next season’s holes and the length of cable for the oceanographic instrument package. We also will try to use a special type of radar to directly measure the rate of ice melting on the underside of the ice shelf.

2008-09:

Helicopter (transported to ASE by LC-130) supporting field work near PIG in 1977.
Photo courtesy of W. McIntosh.

The field work begins by drilling the first hole through the ice shelf. The initial hole will be used for exploration of the ocean cavity using the video camera. A second hole will be drilled nearby and the sub-shelf profiler deployed and monitored throughout the occupation to ensure proper operation. Winter-over AWS and GPS instruments will be serviced, data downloaded (if necessary), and prepared to survive through the next winter. Three additional GPS will be deployed and rigged for wintering over. The total surface time for the drilling, exploration, and instrument deployment phase is estimated at 6 weeks.

Helicopters are required to deploy the shelf-survey team to approximately 30 sites distributed across the ice shelf for mapping of cavity depth, ice thickness, elevation, and gravity. We estimate completing five sites per day with an equal number of flying and non-flying weather days for a total helicopter support requirement of ten days.

2009-10:

The drilling team returns to drill three additional holes for new ocean profiling instruments Additional video exploration may occur depending on results from the previous season. The AWS and the GPSs will be serviced, data downloaded, and readied again for the following winter. On-site work is estimated to require five weeks.

2010-11 and 2011-12:

AWS and GPSs will be maintained annually. Profiler data will be retrieved if problems occurred with Iridium communication system. We would like to keep the surface instruments working for the two-year lifetime of the profilers and would remove surface instrumentation if sub-shelf instrumentation fails.