In Beacon Valley surfaces are older than in Victoria Valley and rocks which have been scoured by wind for thousands of years form ventifacts (see below).
Friday, December 26, 2008
Saturday, December 20, 2008
In addition to taking long cores we also use a small rock drill to take samples from the upper 15 to 20 cm of the groundice. The picture below shows Ron and David opening a pit at the shoulder of a polygon from which they retrieve a small ground ice core (see second picture below). The ground ice here occurs in two different forms: as ice cemented sand and pure ice (light part). Ice cemented sand has only small fraction of ice and consits mostly of sand while the pure ice contains only little or no sediment.
The last days we have strong katabatic winds which generate on the Antarctic Ice Sheet. They warm up due to increasing atmospheric pressure from the Ice Sheet (3000 m elevation) to the valley at 400 elevation; temperature increases can be 10 to 20 degrees. The lenticular cloud in the picture below indicats the winds.
Thursday, November 20, 2008
This year we are drilling permafrost cores. We will analyze these cores to look at the history of the ice. Some of the ice may be as old as ten thousand years. Analyzing this ice may give us an idea about the climate and environmental situation at this time. In addition it may give us a clue if meltwater from snow is infiltrating into the ground. We use the stable isotope signature of water molecules in the ice to identify climate conditions when the ice formed and other processes like evaporation that affected the ice in his historic or modern time. The pictre below shows a setup of the drill with the tent that blocks the wind and the drill mast sticking out at the top. The tent is important since wind chill temperatures here are about -30 to -40°C (-30 to -40°F). While two drillers are working in the tent to take the core, Ron and Tom are describing the core in detail outside the tent. After description the core is packed and stored at -20 C temperature. It will be shipped back to the laboratory at the University of Washington, Seattle.Working all day outside in this cold environment consumes a lot of energy. A good breakfast like butter-fried bagels with jam, peanut butter, or Nutella is a good start for the day.
At the end of our stay in Taylor Valley we visited a research group that works in the ocean at New Harbor. Below is a picture from a pressure ridge near the coast at New Harbor and the diving hole (behing Ron). Diving in this water is very cold, the water temperature is -2 C (28.4 F).
Saturday, November 15, 2008
So here we are and start our investigation. During this field season we will take 10-20 m log cores out of the polygon. The cores will be shipped back home and analyzed for their composition. We hope this will tell us something about the history of the ice.
Thursday, November 13, 2008
Our destination is Taylor Valley where we stay close to the coast at New Harbor. We set up the tents and get settled in. Now we are finally ready to start with our research.
Friday, November 7, 2008
Wednesday, November 5, 2008
After spending the night in either a tent or a snow shelter, the campers spend the second day learning how to operate the radios used for communication in Antarctica. With the high frequency (HF) radio, they were able to contact the South Pole station!Over the next couple days we will continue to get our equipment and food ready to fly out to our field camp.