Dawes Glacier, Endicott Arm

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Dawes Glacier, Endicott Arm

by | Oct 16, 2020

Dawes Glacier starts near the Alaska-Canada boundary and flows northwest for 20 miles (32 km) to tidewater in Endicott Arm, about 100 miles (161 km) northeast of Sitka and 80 miles (129 km) southeast of Juneau, Alaska. The glacier was named in 1891 by the U.S. Coast and Geodetic Survey for Henry Laurens Dawes, a lawyer and statesman in Massachusetts from 1857-1875. The glacier was originally called the Young Glacier by John Muir for Reverend S. Hall  Young, who was a traveling companion in 1880.

The majority of glaciers in southeast Alaska and adjoining Canada are thinning and many of them very rapidly. Some of the largest ice losses in southeast Alaska are occurring at tidewater glaciers such as LeConte, South Sawyer, Dawes, and Muir Glaciers. Tidewater glaciers become unstable when the terminus retreats from a protective shoal into a deep basin and rapid calving of the glacier terminus ensues. Although the retreat may be triggered by climate, these calving retreats become independent of climate as part of a tidewater glacier cycle. Once begun, the retreat phase of this cycle is subject to increasing positive feedback as surface slopes and flow velocities substantially increase at the terminus and throughout the length of these glaciers, causing significant drawdown of the parent ice field.

This phase of the tidewater glacier cycle has been observed to lead to a terminus retreat in excess of 0.62 miles per year (1 km/yr) in southeast Alaska. Because of the magnitude of ice loss for tidewater glaciers is so large relative to non-calving glaciers, retreating tidewater glaciers tend to be the dominant contributor to sea level rise in coastal Alaska. Read more here and here. Explore more of Dawes Glacier here:

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