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Date: 12/27/03
Latitude: 80.78 degrees South
Longitude: 124.49 degrees East
Temperature: −20°C( −4°F)
Wind speed: 14 knots
Wind Chill: −32°C( −25°F)
Wind direction: not given
Elevation: 9,600 feet
Kilometers traveled: 1450

Notes on daily life:
By Dan

We arrived at Megadunes by 03:00 this morning, not much to see apart from a few flags and weather vanes. The surface is extremely hard and flat. The camp is called Megadunes because it is in the center of a huge field of mega–scale snow dunes. The dunes have an average amplitude of about 4m but have an average wavelength of 10km or more. As a result, the dunes cannot be easily discerned from the ground; the best way to see them is from the air or satellite. An interesting feature of the dune morphology is the variable accumulation rate from trough to crest; over part of the dune the accumulation rate is zero cm of water per year and over other parts it can be as much as 5 − 6cm water per year. However, the average accumulation rate is not known. So our first item on the agenda today was the collection of beta cores for Ted Scambos (one of the soon–to–be–arriving scientists). We use beta cores to determine the average accumulation rate.

During the 1950’s and 1960’s the American and Russian governments conducted several series of atmospheric nuclear bomb tests. These tests produced a lot of radioactive fallout in the upper atmosphere. This fallout subsequently spread throughout the world via the stratosphere and was deposited 1–2 years later as a radioactive layer. Because the snow accumulation is preserved every year in Antarctica the radioactive bomb layers can be recovered. By analyzing the radioactivity in each layer of snow it is possible to determine exactly how much snow has fallen since the radioactive layers were deposited. In this way one can work out an average accumulation rate.

Tom and I decided to use the PICO drill to collect the beta cores because it is more compact and has a faster setup and takedown time. We traveled by snowmobile to the nearest downwind accumulation area (about 2 miles downwind) and we drilled a 7m core in just one and a half hours!

The rest of the crew stayed around camp and started to set out the skiway, put up shelters and generally finalize the camp layout.

 

Date: 12/28/03
Latitude: 80.78 degrees South
Longitude: 124.49 degrees East
Temperature: −22°C( −8°F)
Wind speed: 25 knots
Wind Chill: −38°C( −36°F)
Wind direction: not given
Elevation: 9,600 feet
Kilometers traveled: 1450

Notes on daily life:
By Dan

The Megadunes camp is slowly taking shape; the skiway is flagged and is being groomed for ~18 hours per day. Two buildings have been erected; one berthing tent (an Arctic Chief) for Tayloe and Drew and another large rigid–framed tent (a Polar Haven) to be used as a dining facility.

Tom and I drilled another 7m beta core with the PICO drill upwind from the Megadunes camp site. The PICO drill is a non–powered hand auger; it is 3 inches in diameter and a lot of fun to use. The bottom section of the drill is the core collection section; this contains the sharp cutting teeth and the hollow barrel for the core. This bottom section is capable of collecting about 50cm of core at a time. Connected to the bottom core collection section is an upper handle section. The upper handle is composed of a rigid vertical tube about 50cm long with a ~3–foot horizontal steel tube connected firmly on the end. The drillers stand on the surface and use the horizontal steel tube to turn the drill that is down the hole. After each drilling run the entire apparatus must be pulled out of the hole so that the bottom section can be emptied. Then the whole apparatus is fed down the hole again for another run. As the drill gets deeper into the hole, extra vertical sections can be added between the core collector and the upper handle. So, by the end of our 7m beta core we had six 1m extension sections added between the upper and lower sections. It is quite a feat to lift this whole apparatus into and out of the hole, especially in 25–knot winds!

It took us about two hours to set up and drill the beta core. After lunch we took the 2–inch diameter drill out to the upwind site, set it up and drilled a test core to clean the barrel. After drilling the test core we headed back to camp to warm up because the 25+ knot winds had chilled us to the bone. We will head back out tomorrow to drill the chemistry core.

One thing I am learning from this site is that Antarctica does not give up its secrets easily; since we arrived at this site the winds have been very strong constantly, the temperature has fluctuated between 18°C and 25°C and the visibility hasn’t been any better than 200m. This is tough work indeed!