Well, the weather today has been mostly white out, windy, and snowy which means any work outside is challenging and cold. Also, it's not worth risking traveling around the divide with poor visibility. The divide itself is fairly safe but there are large, mile high drop offs to the east and west and there are also some crevasses approaching those areas. To the north there is a pretty big ice fall. Although not a particularly active ice fall, venturing too close to it in poor visibility could be dangerous as we have seen some small debris avalanches come off the fall.
Dave and I opted to stay in camp today and do some odd jobs while Brad, Dom, and Mike continued drilling. Dave tightened all the tie downs for our tents which must be done every couple of days to make sure wind storms don't tear tents apart. I cleaned out the lunch tent and charged satellite phones and the computers we are using for data processing. I made hot water for soups and hot drinks for lunch and Tim and I are leading the charge for a healthy dinner. Tim looked through some videos he made with his Go-Pro camera over the last few days to see if any of them are keepers. He also rigged some stakes made out of steel for us to use for ice flow velocity and accumulation estimates immediately around the ice core hole. We will measure the precise locations of these 9' tall stakes with GPSA Global Positioning System (GPS) is a satellite-based navigation system used to track the location or position of objects on the Earth’s surface. tonight and measure how much each stake is sticking out of the snow. Next May-June we will return and re-measure their location with GPSA Global Positioning System (GPS) is a satellite-based navigation system used to track the location or position of objects on the Earth’s surface. and the height sticking out of the snow to figure out velocities over the course of the year and total year long snow accumulation surrounding the drill hole.
For dinner we will be having chicken, broccoli and rice. I am generally a meat and potatoes kind of cook and not too adventurous, but we will also have a chocolate pudding desert. Now that we have established camp we are planning on rotating cooks on a daily basis in teams of two. Tim and I are a team tonight and Dave will team up with either Brad or Dom. That will leave Mike with the remaining team member. This way, everyone has a cook duty once every three days. Camp duty efforts are shared evenly.
The drill team had already reached 68 meters in depth by lunch so we expect they may reach 80 meters by the end of the day. This is amazing for 3 days of work. Tim has finished most everything on the MET (meteorological) station installation although he needs some sensor cables that were accidentally left at base camp. He has started helping Dave and me with our portion of the project. I'm not sure I have ever actually stated my part of the project but in a nut shell, my goal is to make high resolution maps of ice depth, ice stratigraphy, ice flow velocities and spatial variability of accumulation. When combined with some other information from my GPR data, the ice core chemistry, and MET station data collected over the next year, the goal is to develop numerical models for realistically predicting yearly accumulation along the entire depth of the ice core. In other words, the top layer of the core represents the most recent yearly accumulation. Very little deformation of that layer has occurred because the ice has not moved very far from its original point of deposition. However, as depth increases, layers are progressively thinned by "densification" and also ice flow. Some basic estimates of this thinning are possible, but we are interested in developing some more sophisticated models of layer deformation based on everything known about the ice divide site. One of the major goals is to reproduce precipitation estimates and changes in precipitation over the past 1000 years. To do this, we are combining observed field data with modeling efforts.
This goal may sound complex so an analogy may be helpful: Take a Snickers Bar and pretend the thickness of the bar represents one year of accumulation on a glacier. Then pretend that that Snickers Bar is within the glacier under multiple years of accumulation. If you pull the ends of the Snickers bar apart then the bar is stretched out and becomes thinner and thinner. A Snickers that is stretched out is likely similar to a deep annual layer of ice within the ice core that has "deformed" over many years. The goal is to push that deformed Snickers bar back to its original thickness to estimate accumulation/precipitation that layer originally represented. We want to do this for each annual layer noted within the ice core. Hopefully the Snickers bar analogy helps!
Also, the video below, taken by Cameron Wake, I hope gives you a little bit of an idea about the terrain on the divide and if you look closely the gear drop and campsite are visible.
http://youtu.be/OPQpsVPuvYc
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