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The Alaska Highway crosses numerous terrain units underlined by warm and ice-rich discontinuous permafrost highly susceptible to thermal degradation. For years, this infrastructure, which is essential to transportation in northwestern Canada and Alaska, has been showing signs of road damage induced by permafrost degradation. In 2008, Yukon Highways and Public Works, and its international collaborators, implemented a road experimental site near Beaver Creek (Yukon) to test mitigation techniques aiming to control permafrost degradation. Permafrost investigations were done accordingly to a geosystem approach based on the hypothesis that permafrost has a distinctive sensitivity to climate and terrain conditions at a...
Categories: Data,
Publication;
Types: Citation,
Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Adaptation planning 1-Best management practices,
Baseline 5-Data,
Beaver,
Modeling,
Monitoring 3-Improve Permafrost Mapping, All tags...
Species of Concern: Mammals,
and Monitoring,
landscape scale conservation: Human Activity, Fewer tags
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The Fairbanks Permafrost Experimental Station was established in 1945 near Fairbanks, Alaska. In 1946 vegetation was removed from two plots (the Linell plots) to investigate the impacts of vegetation disturbance on permafrost degradation. We revisited the sites in 2007 to evaluate the permafrost table using probes and direct current electrical resistivity. The permafrost table has expanded downward to 9.8 m at a site where all surface vegetation and organic material was removed. The permafrost surface has remained at 4.7 m depth since 1972 at a second site where vegetation was removed but organic material was left intact. In 2005 a Circumpolar Active Layer Monitoring Network (CALM) site was established at an undisturbed...
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The influence of permafrost growth and thaw on the evolution of ice-rich lowland terrain in the Koyukuk-Innoko region of interior Alaska is fundamental but poorly understood. To elucidate this influence, the cryostratigraphy and properties of perennially frozen sediments from three areas in this region are described and interpreted in terms of permafrost history. The upper part of the late Quaternary sediments at the Koyukuk and Innoko Flats comprise frozen organic soils up to 4.5 m thick underlain by ice-rich silt characterised by layered and reticulate cryostructures. The volume of visible segregated ice in silt locally reaches 50 per cent, with ice lenses up to 10 cm thick. A conceptual model of terrain evolution...
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