Understanding causes and consequences of catastrophic permafrost region lake drainage in an evolving arctic system
4/29/2019
Yesterday we made a trek into the foothills to start working on lake basins in the yedoma (or loess) belt. Starting with clear skies and slight south wind, the day promised to be a warm on. The lake basins we instrumented and cored were impressively large and with distinctive patches, bands, and rings of willows above the deep snow.
Misha focused on coring two overlapping basins seemingly of different ages, while Ben and I rode over increasingly soft snow while traversing broad long hillsides struggling to keep our machines from pulling us downhill. Downhill ski keep digging in to ripening snowpack and made it hard to maintain course. Second basin we reached, we immediately named Shrubby Basin because of wide thickets of very tall willows almost everywhere.
The topic of shrubification (a term that our team botanist Dr. Breen doesn’t care for much) has been a topic of much arctic science armwaving, as its seen as a sign of changing tundra in response to climate warming with implications for wildlife, snowtrapping, and permafrost. Yet no one seems to have taken a look at DTLBs.
On our return to camp we choose a different route negotiating the many steep gulches on our journey back north. Picking the right crossing point is hard and we finally got majorly stuck when crossing one. At one point all three machines and one sled were stuck in softening deep snow over willow infested ravines. After about an hour of tracking down the area, pulling machines from both up and down hill, and some other sweat-generating efforts, we were off again to ride the 50 K back to camp by 9pm.
Today was even warmer as Nori, Andy, Rodrigo and I went to the East to wrap up work in the area. Snow is getting very ripe and tundra is exposed everywhere with ptarmigan seemingly perched on every one. I split off to hit one other site and on return GP crew saw first brown bear of the trip. I spied three northbound geese. Both signs of spring in an increasingly warm and squishy snowscape.