[July 14, 2011]
Day 1 (Thursday July 7): The weather on Thursday cooperated, and our ~3000 pounds of gear and the four of us made it to 76N, 63W in two helicopter flights. Our home for the next week was a site 80 nautical mi from Thule where ICEBridge and the Greenland Inland Traverse (GrIT) intersected. The site was a flat expanse of white as far as they eye could see: the same view in every direction, no topography, and no landmarks. It was humbling, unsettling, and beautiful.
Allen (the mechanic), Ali, Stefan (the pilot), and Lee before heading off to our field site in the red helicopter!
When Lee and I arrived in the second chopper flight, Eric and Erich had moved the gear from their drop-off location (500 ft overshoot) to the desired camp spot and started building a wall for our sleeping area. Because of the winds, we had to build walls out of snow blocks to protect our sleeping tents, our cooking tent and kitchen area, and our latrine. We all set up the sleeping tents, and then Eric and Lee worked on a kitchen area while Erich and I dug a latrine with the ice core. Setting up camp took most of the afternoon and evening, and over dinner we discussed the plan to dig one snow pit and do the first GPR transect the following day.
Day 2 (Friday July 8): Erich and Lee dug an impressive 2 m pit in which they took measurements of snow temperature, density, conductivity (with a Finnish snowfork), bottled snow samples for chemical analysis back in Hanover, and packed cubic feet of snow into cubitainers for Fukushima Cesium detection.
Lee taking snow pit chemistry samples in her clean suit.
Eric worked on setting up the base station GPS and assembling the high-frequency GPR rover “Grover,” while I spent much of the morning entering waypoints into the arcane program on the handheld GPS by hand. Readying the GPR took much longer than expected, and Eric and I did not head out until after dinner (good thing the sun never set). We completed a 1 km traverse along an ICEBridge route, first with a straight route and then backtracking in zig zags to expand our data area. I navigated while Eric hauled both GPRs: Grover and the lower-frequency Ernie.
Ali and Eric doing GPR.
Days 3-4 (Saturday July 9 – Sunday July 10): The plan for Saturday was another 2 m pit adjacent to the previous day’s and a 30 m firn core drilled from the bottom of the first pit. When we woke up, it was overcast and difficult to distinguish ground from sky, but we got started with the pits and coring anyway. After a few hours, though, it became clear that the weather conditions were not going to be conducive to accomplishing much. Eric’s and my pit was filling in as we dug (so much so that in the course of taking 8 Finnish snowfork measurements, the pit filled in 10 cm). We were all getting soaked, and it was far too windy to operate the ice core.
Ali and Eric trying to dig and take snow measurements during the beginning of our three-day storm.
This started more than 48 hours of perpetual shoveling (the first night until 3 am) and waiting as the storm passed. We had to dig out our tents every few hours and construct a new, higher wall upwind of camp.
Ali and Lee’s tent during the storm.
Our “Arctic Oven” (i.e. cook tent) in a drift. Snow built up like this about every hour or two and we had to go outside and shovel.
Days 5-6 (Monday July 11 – Tuesday July 12): It was still windy on Monday, but the storm had abated somewhat. In the afternoon, we were restless, so we decided to excavate the pits we had dug (the second one was entirely filled in and the first partially filled in) to take more Fukushima/chemistry samples and also try out some near infrared photography of the pit walls. After dinner, Eric, Erich, and I decided to go out and take GPR readings along another km of the ICEBridge track and 1 km of GrIT. We learned how deceiving distances can appear on the ice without any landmarks; along the second GRP transect we traversed, we thought we saw a stake and a few objects nearby, presumably left by GrIT. Eric went off to explore, only to discover that the “stake” was his skis and the “objects” our tents, all the way back at camp!
We had a gray sky and poor visibility when the horizon suddenly lit up. Slowly, the crack widened as the clouds lifted and the winds died.
The sky starting to clear around 1 am.
It was the best weather we’d had the entire time on the ice sheet and our originally scheduled Tuesday pick-up was looking likely (this was the painful irony of the weather: if the weather was good enough to accomplish our scientific pursuits, it was also good enough to fly, so the helicopter would be coming!). We thought we had about 10 hours until a potential pick-up and decided to get started on drilling the firn core, which was the post important of our scientific objectives. Since our generator had died in the storm, we no longer had the option of powered drilling. Erich sensed it was possible to get to ~20 m by hand, so we woke up Lee, had breakfast #1 around 2:30 am, and got the core barrels ready. At 4:23 am, Erich and Eric started drilling while Lee and I logged the core.
The core came out in pieces ~70 cm long (each extraction is called a “run”); towards the surface, each run separated into several chunks. Lee and I measured the pieces, recorded the ice layers, and bagged and labeled the core. 9 bags fit into an insulated box, which had to be buried to keep the firn from melting. When the core reaches Thule, it will stay in a freezer until a flight with a “cold deck” goes back to the States.
Eric and Erich drilling the firn core by hand!
We worked straight through until 7:30 am, when we had reached 11 m, and then had breakfast #2. We called Air Greenland to get the disappointing news that the weather there wasn’t looking promising for a take-off. We were told to call back at 12:30 and, in the meantime, organized gear in case we would need to leave later that day. But at mid-day the winds in Thule were strong (we later found out 65 knots!), so we knew we wouldn’t be leaving until Thursday at least. We all crashed and napped/relaxed for the rest of the day.
Day 7 (Wednesday July 13): Because we knew we wouldn’t be leaving Wednesday, we had a leisurely brunch of pancakes and then spent the rest of the day finishing the core, this time with a longer core barrel that could extract over a meter each run. We reached just over 20 m, at which point the firn was so dense/brittle that it was difficult to drill and nearly impossible to extract from the core barrel. It was overcast, windy, and snowing yet again, and we were worried about our prospects of getting out on Thursday. Lee and Erich are sticking around for an extra week to do work around the margin area, but Eric and I were scheduled to leave on Friday the 15th and needed to make it back to catch our flight (though, to be honest, I wouldn’t have been too disappointed to have had an excuse to stay).
Day 8 (Thursday July 14): We woke up to beautiful blue skies and were optimistic about our flying chances. After sorting out some confusion with Air Greenland, whose personnel had changed during the course of our time on the ice, we found out we’d get on flight out on Thursday and then another the next day, weather permitting. Lee brilliantly suggested that we shift around gear/weights so that all 4 people could make it back to Thule together. We had an hour and a half of warning before the helicopter arrived, during which Eric was in the pit taking near-IR pictures of the pit stratigraphy and Erich, Lee, and I frantically packed, dug out the tent stakes (no easy task as some were buried below feet of ice and wind-packed snow), and made a cache of gear for pick-up the following day.
We arrived back in Thule by 1:30, sorted/dried gear, took snow samples to the freezer, and showered for the first time in a week! We had a great night catching up with the other Thule “beakers” and then headed to bed.
View of nunataks, supraglacial lakes, and crevasses from the helicopter.
Friday July 15: Eric and I woke up at 5 am to check in for our DC-8 flight and had just enough time to meet Lee and Erich for breakfast before they headed to catch the helicopter back to the ice to recover the rest of our gear. We saw the helicopter take off just as we were boarding our plane to Baltimore!
The Thule passport stamp.
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