InSAR detects increase in surface subsidence caused by an Arctic tundra fire

Lin Liu; Elchin E. Jafarov; Kevin M. Schaefer; Benjamin M. Jones; Howard A. Zebker; Christopher A. Williams; John Rogan; Tingjun Zhang

doi:10.1002/2014gl060533

USGS · 70114502

InSAR detects increase in surface subsidence caused by an Arctic tundra fire

Lin Liu·Elchin E. Jafarov·Kevin M. Schaefer·Benjamin M. Jones·Howard A. Zebker·Christopher A. Williams·John Rogan·Tingjun Zhang

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Abstract

Wildfire is a major disturbance in the Arctic tundra and boreal forests, having a significant impact on soil hydrology, carbon cycling, and permafrost dynamics. This study explores the use of the microwave Interferometric Synthetic Aperture Radar (InSAR) technique to map and quantify ground surface subsidence caused by the Anaktuvuk River fire on the North Slope of Alaska. We detected an increase of up to 8 cm of thaw-season ground subsidence after the fire, which is due to a combination of thickened active layer and permafrost thaw subsidence. Our results illustrate the effectiveness and potential of using InSAR to quantify fire impacts on the Arctic tundra, especially in regions underlain by ice-rich permafrost. Our study also suggests that surface subsidence is a more comprehensive indicator of fire impacts on ice-rich permafrost terrain than changes in active layer thickness alone.

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Geophysical Research Letters Article

Source-reported bounding extent: 68° to 72° latitude; -159° to -147° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Lin Liu, Elchin E. Jafarov, Kevin M. Schaefer, Benjamin M. Jones, Howard A. Zebker, Christopher A. Williams, John Rogan, Tingjun Zhang. 2014-06-02. InSAR detects increase in surface subsidence caused by an Arctic tundra fire. https://doi.org/10.1002/2014gl060533

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