Monday, August 29, 2011

How fast does a glacier flow?

One of the main things we are often interested in is the speed of glaciers, and how variable it is. For that we use a variety of methods. GPS works really well, but low down on tidewater glaciers, there are so many crevasses that we don't like to leave expensive instruments. This year we had an exciting opportunity to test a new method. It measures the displacement of ice by looking at the difference in returned radar phase. It is possible to get a velocity field within a few minutes of measurements only. The image below shows the instrument, which we had on loan from Gamma Remote Sensing.

To verify the results of the radar we also did some more traditional surveying. For this we deployed targets onto ice towers (seracs) from a hovering helicopter. These targets consist of a prism reflector, which is then surveyed with a total station from the side of the glacier.

1 comment:

  1. I have gone through the site and read all blogs and this is a nice one:

    GPS Gamma surveys