Periglacial weathering and headwall erosion in cirque glacier bergschrunds

  title={Periglacial weathering and headwall erosion in cirque glacier bergschrunds},
  author={J. W. Sanders and Kurt M. Cuffey and Jeffrey R. Moore and Kelly R. MacGregor and Jeffrey L. Kavanaugh},
Glaciers produce cirques by scouring their beds and sapping their headwalls, but evidence to constrain models of these processes has been elusive. We report a suite of environmental measurements from three cirque glacier bergschrunds, including the first temperature series recorded at depth throughout most of an annual cycle. Compared to the ambient air, the bergschrunds were colder in summer and warmer in winter. Freeze-thaw cycles were rare, and relatively stable subfreezing temperatures… Expand

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