Glaciers Convergent, Advancing, and Retreating

Explanation: We are peering up the amazing College Fjord while flying over southeast Alaska in the middle of June of this year. How many glaciers can you count in this image?

If you mouse over (or click on) the above photo, you will see red arrows denoting, clockwise starting in the bottom left of the image, a series of retreating "hanging glaciers" -- Wellesley, Vassar, Bryn Mawr, and Smith Glaciers -- pouring directly into the waters of College Fjord. In the center of the photo is massive Harvard Glacier, and in the upper right is Yale Glacier.

Moreover, the yellow arrows show convergent glacial streams higher up, all contributing to Harvard Glacier on the left and Yale Glacier on the right. (In this photo, we are facing east, so north is to the left and south to the right.)

Harvard Glacier itself is a tidewater glacier and, to give you some perspective here, its face is 1.5 miles (2.4 k) wide.

Interestingly, comparing photos taken in 1909 and 2000, Harvard Glacier has apparently advanced about 0.8 miles (1.3 km) during that period, whereas adjacent Yale Glacier has been retreating at two and half times the rate that Harvard has been advancing. Why the difference? It is likely because of differences in topography and dynamics of the flow of the terminus of each glacier; Harvard Glacier itself apparently is not growing in volume.

College Fjord, as viewed from a bit further north, showing more
of the icefields along this part of the Chugach Mountains in
Chugach National Forest in southeast Alaska.

More of the glacial-fed waters of the College Fjord area,
from a bit further south. Harvard and Yale Glaciers are in the upper left.

This is the realm of humpback whales, sea lions, salmon, and sea otters ...
and moose, deer, black bears, and brown bears.

Peering nearly straight down, here
we see Barry and Coxe Glaciers below us,
with Harvard and Yale Glaciers and College Fjord
in the background.

Prince William Sound and College Fjord are
popular tourist destinations, but being
about 100 miles from Anchorage,
they are accessible only by air or boat.

This is a truly amazing landscape
being studied for global implications
of climate change.

Information:
     Molnia, B.F. 2007. Late nineteeth to early twenty-first century behavior of Alaskan glaciers as indicators of changing regional climate. Global and Planetary Change 56(1-2):23-56.
     Sturm, M., D.K. Hall, C.S. Benson, and W.O. Field. 1991. Non-climatic control of glacier-terminus fluctuations in the Wrangell and Chugach Mountains, Alaska, U.S.A. Journal of Glaciology 37(127):348-356.

EPOW - Ecology Picture of the Week