Friday, December 21, 2007
December 22, 2007
WAIS Divide camp Antarctica
Time: 6 am
Latitude: 79° 28.10’ S
Longitude: 112° 3.56’ W
Elevation: 1820 m (5919’)
Temperature: -12 °C ( 10 °F)
Wind speed: 0-9 km/h (0-5 mp/h)
Wind Chill: ~ -15°C (8°F)
Visibility: 5 km (10 miles)
Clouds: clear to partly cloudy
Wind direction: w
Relative Humidity: 84%
Barometric Pressure: rising
Breakfast: eggs, omlettes, toast-muffins, bacon, sausage
Yesterday was the work day as promised. As if everyone had cabin fever and they had to be outside as much as possible - and it was sunny and "warm". Snow was plowed, shoveled, removed, and melted. My task for the day was to work with Inger and Anais to take Anais's equipment, for doing the down-hole temperature measurements, out to a hole that was dug a year ago near camp. Actually the hole is 1/4 mile from camp. We also had to find shovels etc to start digging a series of snow pits near Anais's equipment for a snow pit project. Anais's project will basically drop a digital thermometer down the old hole - which is like a ice core hole since it is only about 20 cm (8 ") across and hundreds of meter deep - and measure the temperature at a predetermined set of intervals down the hole. The temperature at which snow is depositied is actually retained (to some degree) as it is covered over by and insulated by the next layer of snow. What Anais will measure is the temperature of the atmosphere at a number of times back in the past, now retained in the layers. Now this is not 100% reliable, very difficult to measure since the changes in temperature are very small, and not the type of measurement used when you see information on climate change temperatures. Anais's measurement is a way to support temperature measurements determined by other methods such as using the more precise oxygen isotope ratio method - but more on that measurement another time.
Our other project was to dig a series of snow pits. The purpose for this is for use by a film crew that is scheduled to arrive in Januray. The first snow pit is approximately 2.5 m x 2.5 m (8' x8') and 200 cm (6') deep. Then only 15 cm (6 ") away will be a longer 2.5 m x 5m pit (8' x 15') snow pit. When you climb down insdie the larger pit, cover it with plywood, and then look at the wall between you and the smaller pit, what you see is the Sun illuminating the snow wall between you and the smaller pit. In this illuminated snow wall you can see the layering of the snow/ice. These layers represent wind blown layers, frost layers, and annual layers of snow. Since the accumulation of snow in this area is about 25 cm (10") a year we will be able to see about 8 years worth of snow accumulation in our illuminaed pit. This is a very good way to observe/measure the way snow accumulates in this area and use it as a guide for determining annual layers in the longer ice core. In your snow pits you can also collect and analyze small 2 cm portions of the snow/ice from top to bottom to determine snow chemistry. Maybe we will get to the snow chemistry maybe not.
Now to get all these projects going I was supposed to get a snowmible started, grab a Nansen sled, and haul all our gear the 1/4 mile out to the digging location. This is Antarctica, and there was just a major storm, and it is cold, and things take a "little" bit longer. So, 2 hours later, I was still without a working snowmobile. Lucky Don one of our mechanics took pity on me and got us going. Sometime about 11 am, after an early start, we were finally ready just top start with Anais's equipment set-up and our snow pit. Though by the end of the day, Anais was set-up and Inger and I had snow pit #1 finshed. And yes, I slept well last night.
Finally able to upload images here
One is of my tent and the moat formed around it by the storm, one of me trying to start a frozen snow mobile (unsuccessfully), and one of Inger and the pit she largely dug (and I mostly watched).