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Glacier mapping with LiDAR

I spent three days last week mapping glaciers using ground-based LiDAR. The instrument is able to measure very precisely. Marainne Okal and Thomas Nylen from UNAVCO came out to Lake Hoare to run the instrument and to teach me how to operate the instrument. We intend to repeat the mapping at the end of the season to determine change (ablation and movement).

We mapped a glacier cliff and basin on Canada Glacier for the first two days. The instrument captures 2000 points a second that are organized into x, y, and z dimensions. These points can be georeferenced into lat/long/elevation. The LiDAR mapped the cliff and basin with an accuracy of 1 cm or better. Here are some photos of the cliff (left)and basin (right):



The third day we ventured to Don Juan Pond rock glacier via helicopter. Don Juan Pond is a hyper-saline lake in Wright Valley. The lake is very unique and is a protected area. Right above the lake is a rock glacier (a glacier that is covered with rock debris). We mapped the entire lower half at 10 cm and subsampled smaller plots at 1 cm accuracy.

Rock glaciers occur through out the world including the Western US. Similar features were recently found on Mars (see here). The similarities between the Dry Valleys and Mars are rather astonishing.

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