Made it back to the lower 48. The samples remained frozen throughout the trip and will remain frozen until we start processing them. This trip has been a whirlwind – but fun. Dave and Peter made this an extremely successful sampling! Alaska is such a beautiful place and a great place to study. I did not see any polar bears, even though the last day I claimed I saw something peculiar that looked like a white animal (it was likely just piled up snow). We did see some arctic foxes, musk oxen, and moose though!
The landscape in this area is so beautiful and very interesting things happen in permafrost. Last summer I wrote about solifluction lobes and polygon wedges but this spring I want to introduce pingos. Pingos are another modification of the landscape due to the uniqueness of the freeze/thaw cycles and permafrost. It was hard to get a good photograph of these pingos but they were abundant!
Pingos are mounds of earth-covered ice. They are formed from the draining of a lake or from groundwater. If we recall some of the unique properties of water, 1) water is densest at 4° and 2) less than 4° it expands
then we can understand why pingos form in permafrost environments. Basically, when a lake drains (the bottom of the lake stays ~4° until drained) where this condensed water then freezes and expands up wards creating an ice hill! With a warming climate, there are fractures that form in the active layer of permafrost which induces more melting. This melting can cause a pingo to collapse which, in turn, can then act as another lake! Pingos can host animals, act as a navigational point, or be used for site seeing or for hunting purposes. Better described elsewhere, check out Dave’s brief informational video. (He said it’s his most popular video on the web, for good reason, they are pretty cool!)
More to come as I start processing this fancy dirt! – Kali
Dave was fundamental in those two days of sampling, so his work was done. He left back for Fairbanks Tuesday morning. Peter and I started working on preparing the cores for further analysis at OSU. Our goal was to separate the cores into different depth classes. We got a system down where I would cut the cores into 7.6 cm increments and then Peter would use a bulk density corer and hammer into the cut piece to get the outside, presumably contaminated outer layer off. Our system worked well but it did take a substantial amount of time. We had extensive cleaning practices to follow between each sample to not cross contaminate.
We took turns playing our favorite music, good thing we shared a similar taste in music. This part of the project took us two and a half days to complete which gave us enough time to clean up the work space, pack up our gear, and return borrowed items. Thankfully, all of the samples fit into 2 coolers which will be way easier to navigate than 5. The goal is to keep them frozen during transit. Our dry ice has sublimated so we are using frozen powerade bottles to keep them nice and cold. We are hoping for an easy travel day tomorrow!
The sun came out and the wind gave us a break! Sunday morning went fairly smooth, with the exception of the rod breaking where the motor and the drill bit attach. We resorted to taping to the two pieces together (not ideal but we did what we could with where we were at). You can see how big the auger is and how it moves in the video. We started with two people working the auger (typical) but eventually found that Dave was the most efficient at handling this thing. First of all, it is HEAVY. Second, you have to keep this thing in motion (up and down so that the auger would not freeze to the surrounding earth). Basically, the heat from the friction was enough to have slight melting but as soon as you would turn the auger off, it would simultaneously freeze. This deemed to also be an issue for the sample that was within the auger itself. So, we would have to really work at dislodging the sample when this would happen. We found ourselves strangely happy when the core sample was loose within the auger. It’s the small things..
We were moving at a pretty rapid pace. We had expected that we would get a core/hour. Throughout these two days, we were getting a sample in ~20-30 minutes! Which was great. I was beginning to think that it was not a big deal that we lost our first day and that we would be able to make up for that time without any problems.
As some of you know, fieldwork is never that easy, I mean, most things are never that easy. The missing rod was becoming a dramatic situation. That area was not that secure, so there was some pretty intense wobbling. This made it even more difficult to handle the auger. Sunday night Dave cut off the top of a rubber boot to put around the area (which happened to fit pretty well) where the motor and drill attached (where that broken rod once lived). We also constructed a backup device to secure that area if the rubber boot did not work out. We used this boot top for the remainder of sampling. By Monday evening, we decided that the rig was just too dangerous to keep going. It was so wobbly and was a big issue because our precious kneecaps and, at times, our faces were right there (less than a meter away). If this thing were to come apart while operating, it could have been a pretty bad scenario. Fast moving, sharp metal – no thanks. Ultimately, we ended up getting the cores we wanted at distance classes of 10, 50, 100, 300, and 1000 m with some field duplicates. Overall, we got majority of the samples we wanted and in just 2 days! Pretty remarkable. A ton of hard work went into getting these samples. Patrik, the pilot, must have thought we were sort of crazy, he told me we looked like elves out in the field. He also inspired me to change the title of my thesis to “Fancy Dirt”.
Today was our first day of sampling. We were a bit overweight with us and all of our gear heading into the field, so Dave took a separate flight into Noatak village where he would get picked up after Peter and I and all of our gear would be dropped off near the haul road. Conditions were harsh this morning. It was sunny but extremely windy. So windy and cold, in fact, that my eye lashes were sticking/freezing together! It took me a moment to get myself situated, my hands were frozen too, and to mentally prepare that this was going to be how sampling would likely be during this sampling. It was intense! There was snow covering most of the surface and we were able to see some pretty obvious directional patterns of the fugitive dust near the road.
We put the SIPRE auger together and as we were trying to start the motor, which seemed flooded, Peter’s extraordinary muscles broke the motor cord! Under these conditions, this was not something we wanted to deal with in the field so, feeling a bit defeated, we headed back to Kotz to take care of the motor issue and to prepare back up plans.
It’s hard to describe the mood this evening, things seemed awfully grim, but Dave’s patience persevered and he got the motor working again. We also put together the trough to cut the cores in, so the day was not a total loss. We were ready to get back out there and planned to work some pretty long hours the following days.
Cue beautiful landscape photo for stress relief from this day.
After hauling 5 full coolers and heavy bags of personal gear, I made it back to sunny Kotzebue! Peter picked up Dave and I from the small Kotzebue airport and we hauled our gear to our bunkhouse which is near the Park Service station. We are staying in Kotzebue throughout our stay and will take a helicopter to and from our sites over the next few days. Patrik, the Swedish pilot that we flew with last summer, will be our pilot again this sampling trip.