Glaciers and Ice Sheets
I made 12 trips to Antarctica, ten of which involved research into accumulation processes. The images of snow are from the surfaces of the East and West Antarctic Ice Sheets, where wind dominates sculpting. I made only one trip to Greenland and got my best images from a helicopter ride along the coast.
Abandoned Glacier Valley in Greenland: I took this photo along Greenland’s east coast while flying. Much sediment has been filling the valley.
Eroding snow in West Antarctica revealing layers of different grain size. Wind was from left to right.
Eroding sastrugi in West Antarctica: Sastrugi are wind lanceolated forms usually occurring on windward slopes in Antarctica. Although appearing to be an erosional feature, these slopes are accumulating, as opposed to sand dunes where they are eroding.
Hoar bow in West Antarctica: On 7 December 2000 this hoar halo resulted from sun penetrating the snow surface and then sublimating old snow to about 10 cm depth. The evaporated molecules rose above the surface and then froze into hoar crystals that refracted and scattered light of various colors to form this surface hoar bow.
Isolated Sastrugi in East Antarctica: The dense snow was undercut by wind to the point where the leading edge into the wind then sagged.
Sastrugi on Leverett Glacier Antarctica: I took this silvery image high up on the Leverett Glacier near where it originates on the high plateau. Look closely and you can see upturned snow layers, as though the glacier had undergone upheaval.
Snow Fingers in West Antarctica: Snow fingers are kilometer-long triangular areas of wet snow that I observed in early December 2000 when temperatures in West Antarctica exceeded 40 degrees F. From an airplane on 30 December, they appeared like giant dendrites migrating from a large dark and presumably wet area. To my knowledge, they have yet to be explained.