Highlighting Greenlandic Historical Ice Speeds [HiGHSpeed]

This project is important because we only very little of how the ice sheet has behaved prior to the arrival of modern satellites. Recently most of the major outlet glaciers in Greenland have sped up, delivering more and more ice into the ocean. This makes the sea-level riser faster, and is of great and emminent for society. My project will examine whether the current fast flow is unique in a longer term perspective, and if the ice may have reached a tipping point unlike previously seen. This project will be the first to measure past speeds, and will provide modellers with a much needed knowledge of the stability of the Greenland Ice Sheet.

In Greenland more than 200.000 photographs have been recorded from the air from 1925-1987. This record is unique in its exsistence, and offers one of the best ways of learning of past ice sheet behaviour. Often the aerial images covering the same piece of land were recorded with an overlap in time. When several images exist of the same stretch of ice surface features such as crevasses can be tracked from one image to the other, ultimately resulting in a complete map of surface speeds that can be compared to modern maps derived from satellite images.