Greetings from the freshly showered and clean clothed GreenTrACS team at Summit Station! When we left Summit 6.5 weeks ago, we had 23 empty ice core boxes. By the time we reached core Core site 16, we only had two empty boxes left! The limited box space meant that Core 16 had to be shorter than the other cores. After 24 quick meters, we officially finished the drilling for the 2017 season! We collected a total of 256 meters of firn in 9 cores, more than we ever thought we would manage. In addition we did one last radar spur and performed a kite aerial photography survey.
|Gabe and Forrest are excited to perform a Kite Aerial Photography Survey at Core Site 16|
After just two short days at Core site 16, we started on the 220 km journey to Summit Station. We split the trip into two days, with Karina, Tate, and Gabe sharing one last, stinky night together in “hasty” camp. On the morning of the 19th, Gabe was picked up by twin otter from our “hasty” camp 110 km from Summit. With his sleep kit and personal bag he left us to collect the items at cache 3 and the abandoned snow mobile at cache 2. After waving the plane off, Bob, Forrest, Tate, and Karina took down the camp and set out on snow mobiles to Summit. Bob and Tate had to slowly drove the radars, but Forrest and Karina rushed to Summit camp as fast as they could. The fast team arrived in late afternoon, just in time for a shower before dinner. Tate, Bob, and Gabe arrived just as dinner was finishing.
Our first night at Summit was a blur of seeing old friends, meeting new ones, and stuffing our faces with as much food as possible. It was so nice to sleep in the Arctic Oven tents already erected at Tent City, rather than set up our own mountain tents. By the next morning, we were well rested and ready to keep working. Karina and Forrest woke up early to fly to Cache 2 and pick up the ice cores and other cargo. They were accompanied by Steve Kirsche, a grade school teacher at Liberty Pines Academy in St. John, Florida. Steve is participating in PolarTREC (Teachers and Researchers Exploring and Collaborating), a program where “K-12 teachers spend 3-6 weeks participating in hands-on field research experiences in the polar regions”. Steve is working with Dartmouth researcher Ian Baker on a project entitled “Dynamic Observations of the Microstructural Evolution of the Firn.” You can learn more about the project and Steve’s experiences on his blog, http://www.Polartrec2017.com. His main task has been to help collect an 80 m ice core near Summit Station, but we managed to pull him away for a morning to help us dig out the cached ice core boxes. Steve might not have known how much digging he was offering to do. Drifting at the cache site buried the core boxes more than 1.5 meters deep!
|Steve, Forrest, and our very helpful pilot digging out ice core boxes at Cache 2|
|Our ice core boxes, safely stored in a freezer trench at Summit Station|
That afternoon, Tate headed out with the Twin otter to collect the last cache items at Cache 1. While he was in the air, the rest of the team started sorting through cargo. We needed to get all our cargo relabeled and ready to ship to Kangerlussuaq. This involved making labels, separating out hazardous gear, and taking apart the radar sled systems. All in all the cargo preparations were fairly quick and easy thanks to the help of the Summit cargo crew.
Besides getting our gear ready for shipment, we’ve also spent a good deal of time doing more science! Bob has spent the past few days working on a totally different science project, a strain survey to study ice motion around Summit Station. Bob has placed 25 survey stakes within 40 km of Summit Station. Each year, he or his colleagues measure the exact locations of the stakes using high precision GPS. By tracking the position of the stakes from year to year, Bob measures the flow and strain of the ice near Summit. Bob and Tate spent a whole day snowmobiling to measure GPS locations at many different stake sites, while Gabe skied out to two stake sites in the clean snow zone.
|Gabe loved skiing for science!|
Karina and Gabe dug one last snow pit in the clean snow zone. In addition to the typical density, temperature, and stratigraphy measurements, they collected large samples of ultra clean snow for Dartmouth researcher Mukul Sharma. This snow will be tested for osmium concentrations and isotopic ratios, to help understand anthropogenic osmium pollution resulting from increased platinum extraction for use in modern day catalytic converters (For more about this research, see Chen et al, 2009).
|Karina wore not one, not two, but three pairs of clean gloves for the Osmium sampling|
On June 22nd, Bob presented a science talk to the researchers and staff at Summit Station. Back in 1997-1998, Bob worked at Summit Station for a full 11 months, making him a bit of a legend here. Bob talked not only about GreenTrACS research but also the many different science projects at Summit. He talked about his strain survey, the Greenland Inland Traverse, and a project that used drone photography to create a digital elevation model to understand snow drifting around summit station.
Gabe, Tate, and Karina got back to Kangerlussuaq on June 23rd. Forrest has already left us – he hitched a ride on the twin otter to Iceland, and is going to meet his family at a reunion in Ireland. Bob is staying at Summit Station for a few more days to finish up his strain survey and also to participate in a station safety audit. Bob is only a little concerned about letting three young grad students run wild in Kangerlussauq without adult supervision. In Kangerlussuaq, there’s more organizing and packing to do. While we’ve had an awesome time here on the flat white, we can’t wait to see the mountains, running water, and maybe a baby muskox!
|5 pallets of gear and ice cores were loaded onto the Herc before we could board|