Thermal and hydrological observations near Twelvemile Lake in discontinuous permafrost, Yukon Flats, interior Alaska, September 2010-August 2011

Steven M. Jepsen; Joshua C. Koch; Joshua R. Rose; Clifford I. Voss; Michelle Ann Walvoord

doi:10.3133/ofr20121121

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Thermal and hydrological observations near Twelvemile Lake in discontinuous permafrost, Yukon Flats, interior Alaska, September 2010-August 2011

Steven M. Jepsen·Joshua C. Koch·Joshua R. Rose·Clifford I. Voss·Michelle Ann Walvoord

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Abstract

A series of ground-based observations were made between September 2010 and August 2011 near Twelvemile Lake, 19 kilometers southwest of Fort Yukon, Alaska, for use in ongoing hydrological analyses of watersheds in this region of discontinuous permafrost. Measurements include depth to ground ice, depth to water table, soil texture, soil moisture, soil temperature, and water pressure above the permafrost table. In the drained basin of subsiding Twelvemile Lake, we generally find an absence of newly formed permafrost and an undetectable slope of the water table; however, a sloping water table was observed in the low-lying channels extending into and away from the lake watershed. Datasets for these observations are summarized in this report and can be accessed by clicking on the links in each section or from the Downloads folder of the report Web page.

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Source-reported bounding extent: 66.41666666666667° to 66.48333333333333° latitude; -145.6° to -145.33333333333334° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Steven M. Jepsen, Joshua C. Koch, Joshua R. Rose, Clifford I. Voss, Michelle Ann Walvoord. 2012. Thermal and hydrological observations near Twelvemile Lake in discontinuous permafrost, Yukon Flats, interior Alaska, September 2010-August 2011. https://doi.org/10.3133/ofr20121121

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