Radio Echo Sounding on a Valley Glacier in East Greenland

Radio Echo Sounding of the Greenland Inland Ice

Radio echo sounding has been used for a number of years in the exploration of polar ice such as the inland ice in Greenland and Antarc­ tica. By means of this technique a number of important glaciological and geophysical parameters may be deter­ mined. Examples are ice thickness, bedrock topography and structure, stratification patterns which are used for climate and flow patterns studies, and ...

Rapid retreat and acceleration of Helheim Glacier, east Greenland

[1] A significant amount of the measured coastal thinning of the Greenland ice sheet may be due to recent acceleration of outlet glaciers. Using remote sensing, we measured two major periods of speedup on Helheim Glacier between 2000 and 2005 that increased peak speeds from approximately 8 to 11 km/yr. These speedups coincided with rapid retreats of the calving front, totaling over 7.5 km. The ...

Mapping subglacial surfaces of temperate valley glaciers by two-pass migration of a radio-echo sounding survey

A New Coherent Radar for Ice Sounding in Greenland

This paper will discuss a new multifrequency dual channel coherent radar depth sounder for sounding ice. This sounder is unique, since it is a fully coherent chirp radar designed to operate at low (1,500ft) as well as high altitudes (30,000ft). The dynamic range of the radar is sufficient for simultaneously imaging both the top and bottom returns from ice without the need for data blanking or S...

Evidence for non-tidal diurnal velocity variations of Helheim Glacier, East Greenland

We have used tide-gauge data from near Helheim Glacier, East Greenland, and GPS data acquired on the glacier to investigate the spectra of tidal forcing and flow response. For both the tidegauge and GPS time series, we calculated amplitudes and phases for a harmonic expansion using a limited set of harmonic constituents. We find that the semidiurnal constituents of the glacier flow are well mod...