Tuesday, August 16, 2011

Thermokarst Exploration near Council

Today the NGEE team spent the day exploring the geomorphology, hydrology and vegetation near Council. We were able to observe an outstanding array of features indicative of the transitional nature of this landscape. On the hillslopes, we witnessed solifluction (or active layer detachment and transport) as well as shrubification. On flatter ground, we walked through many different thermokarst features, stepping from wet sedges in the middle of the thermokarsts (the first step is always a surprise...) to higher and dryer shrubs on the banks of the features.

We used a probe to measure the spatial variation in the active layer thickness , which often ranged from 30cm on the banks to >1m in the center of the thermokarsts; this variation is expected to drive a variety of above ground vegetation and below ground microbial ecosystem processes that feedback to climate. Not only were the transitions in moisture, vegetation, and active layer sharp, but the heterogeneity of features within a small distance was striking: thermokarsts, drained lakes, and patterned ground formations were all evident in close proximity. Witnessing textbook examples of such a variety of permafrost degradation features first-hand was awesome - it fostered plenty of team discussion about where to select sites for detailed study.

After investigating lodging possibilities for a field camp in Council and experiencing the generous hospitality of Council townspeople, we headed back for our last night in Nome. On the way back, we spotted reindeer and grizzly bear, as well as several large birds and small critters. What a day.

Tomorrow early morning we board a small charter plane to survey this and several other areas from the air – we expect another exhilarating day of observing these features from another perspective.

All photos in this post were taken by Roy Kaltschmidt and are under copyright by Lawrence Berkeley National Lab