The Yakutat Glacier during the 1894-1895 Alaskan Boundary Survey ended near a terminal moraine on a flat coastal outwash plain. By 1906 the glacier had retreated from the moraine and a new lake was forming. Harlequin Lake. Surveys of the terminus of the glacier indicated a retreat of 1 kilometer in that decade. From 1906-1948 the glacier retreated an additional 5 km. From 1948-1958 the glacier retreated 3.6 km. From 1958-2008 the glacier has retreated another 3-4 km. By 1982 Harlequin Lake was quite large, too large it seemed to me, being lost in the fog on its waters trying to find the terminus. The retreat is evident in comparing the Yakutat B-3 quadrangle from 1958 photography and a 2008 satellite image of the glacier. 
The orange-brown line is the margin of 50 years before. Today the glacier is the focus of a new study by the University of Alaska, led my Roman Motyka, Martin Truffer and Chris Larsen
They have set up a time lapse camera to record frontal changes. The goal is to understand the controls on calving into Harlequin Lake of this glacier. More amazing than the retreat has been the observed thinning of the glacier. The glacier has thinned by more 200 m on average according to the preliminary thickness change maps from the UAK project. The Yakutat Glacier does not have a high accumulation zone and the recent increase in the snowline elevation and thinning of the glacier have led to a substantial shrinking of the accumulation zone. For a calving glacier to be in equilibrium it needs to have at least 60 % of its area snowcovered at the end of the summer. 
Yakutat Glacier Rapid Retreat
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