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Full-Text Articles in Glaciology
Melt Regimes, Stratigraphy, Flow Dynamics And Glaciochemistry Of Three Glaciers In The Alaska Range, Seth Campbell, Karl Kreutz, Erich Osterberg, Steven Arcone
Melt Regimes, Stratigraphy, Flow Dynamics And Glaciochemistry Of Three Glaciers In The Alaska Range, Seth Campbell, Karl Kreutz, Erich Osterberg, Steven Arcone
Dartmouth Scholarship
We used ground-penetrating radar (GPR), GPS and glaciochemistry to evaluate melt regimes and ice depths, important variables for mass-balance and ice-volume studies, of Upper Yentna Glacier, Upper Kahiltna Glacier and the Mount Hunter ice divide, Alaska. We show the wet, percolation and dry snow zones located below 2700ma.s.l., at 2700 to 3900ma.s.l. and above 3900ma.s.l., respectively. We successfully imaged glacier ice depths upwards of 480m using 40–100MHz GPR frequencies. This depth is nearly double previous depth measurements reached using mid-frequency GPR systems on temperate glaciers. Few Holocene-length climate records are available in Alaska, hence we also assess stratigraphy and flow …
Glacimarine Sedimentation Processes At Kronebreen And Kongsvegen, Svalbard, Laura M. Kehrl, Robert L. Hawley, Ross D. Powell, Julie Brigham-Grette
Glacimarine Sedimentation Processes At Kronebreen And Kongsvegen, Svalbard, Laura M. Kehrl, Robert L. Hawley, Ross D. Powell, Julie Brigham-Grette
Dartmouth Scholarship
Tidewater glaciers deposit sediment at their terminus, thereby reducing the relative water depth. Reduced water depth can lead to increased glacier stability through decreased rates of iceberg calving, glacier thinning and submarine melting. Here we investigate sedimentation processes at the termini of Kronebreen and Kongsvegen, Svalbard. We mapped the fjord floor bathymetry in August 2009 and calculate sedimentation rates based on our bathymetry and that from a similar study in 2005. A grounding-line fan is developing near the current position of the subglacial stream. An older, abandoned grounding-line fan that likely formed between ~1987 and 2001 is degrading near the …
Microstructural Evolution Of Fine-Grained Layers Through The Firn Column At Summit, Greenland, R. Lomonaco, M. Albert, I. Baker
Microstructural Evolution Of Fine-Grained Layers Through The Firn Column At Summit, Greenland, R. Lomonaco, M. Albert, I. Baker
Dartmouth Scholarship
We present a microstructural characterization of fine-grained layers from the top 90 m of firn from Summit, Greenland, performed using a combination of scanning electron microscopy techniques including secondary electron imaging, energy-dispersive spectroscopy and electron backscattered patterns, and X-ray microcomputed tomography. The impurities in the firn, both soluble impurities and dust particles, were found largely in the grain interiors. Both c- and a-axis pole figures do not show strong evidence of a preferred orientation of the grains even at the bottom of the firn column. The firn structure became increasingly anisotropic with vertical alignment in the top 3 m, probably …