MANY GLACIERS IN THE SAME PLACE
College Fjord is located just off of
Alaska's Prince William Sound, which you
can see in the map at this link. Also, look
at this satellite image showing the glaciers
side by side. This is on Alaska's southern
coast near Whittier. As the name would
suggest, the glaciers are named after
colleges. I have labeled many of them in
the picture to the right.
|You can click in each picture to get a larger version. Use the "back" button to return from
the larger version. If the picture snaps down to fit your screen, put the mouse pointer in it,
wait for an icon to appear in the lower right, and click the icon to see the large version.
Here are some more of the glacier names.
It is a little hard to tell from this picture,
but Harvard Glacier and Yale Glacier are
each at the end of a separate arm of
College Fjord. That bit of land between
them actually extends out quite a distance
toward the camera. Check that satellite
Radcliffe Glacier is a tributary glacier of
Harvard. So is Baltimore Glacier. What
would people in those places think of that?
So how could some glaciers advance while other glaciers that are nearby are retreating? For
example, Harvard Glacier is advancing while Yale Glacier is retreating, even though they are
side-by-side and they originate in the same snowfield. Most of the other College Fjord glaciers also
show signs of having retreated.
In general, many (but not all) tidewater glaciers that lose mass by calving are known to defy climate.
Here is a paper that discusses the matter while describing the 2002 closing of Russell Fjord by
Hubbard Glacier. Here is my page on Hubbard Glacier.
Such glaciers also calve into unusually shallow water, which seems to make a difference. The shallow
water is often caused by the glacier's terminal moraine -- the sediment and junk dropped by the
glacier as it loses its ice. In general, the condition of the bottom of the fjord can govern how
rapidly the glacier does or doesn't grow.
This link takes you to the abstract of a similar paper.
More discussion at this USGS site.
In a closer picture, Yale Glacier shows signs of
having pulled back from the water. These pictures
were taken in June, 2007, but it is interesting to
compare them with a Sept., 2007 picture. By
September, most of the snow was gone from the
mountain tops, but it was close enough to winter then
so that the snow was about to come back.
Not the glacier, though, which has been retreating
at about 50 meters per year (164 feet per year)
since 1931. Glaciers respond to regional climate on
much longer timescales than just the transition from
winter to summer to winter. Glacier response can
The next picture (to the left) there is the advancing
glacier, Harvard Glacier. It has been advancing at
about 20 meters per year (66 feet per year) since
1931. The interesting thing is that both are
side-by-side, exposed to the same climate. Not
only that, both start in the same snowfield, about 20
miles back. So, although glaciers do respond to
climate, there must also be something else driving
the behavior of these glaciers.
These are tidewater glaciers, glaciers that end in
some body of water connected to the ocean. For
such glaciers, the dynamics of the interaction with
the bottom of the body of water seems to influence
the motion more than regional climate. See this
NASA site for a brief look at these two glaciers and
their dynamics as well as a look at some other
Go to the bottom of this page for some more
discussion of this, largely copied from my page on
While we are at it, have a look at some of the
nearby wildlife. I think these are harbor seals (to
the left), but I am not very good at identifying
|Continuing on around from Harvard Glacier, we come to Smith Glacier (Right) and
Bryn Mawr Glacier (Left). Notice that each of these shows signs of retreat in
the form of bare ground which the glaciers once covered. That looks like a
couple of icefalls, high on each glacier. That is like a waterfall, except with ice,
where the slope gets steep and the ice gets very jumbled as it tumbles down.
Here are the same two glaciers, Bryn
Mawr and Smith. But look how still
the water is allowing reflections of the
glaciers and mountains behind them.
And, in a rather strange-looking
picture, the seals got to look at the
|Here, we are continuing on around College Fjord with Vassar Glacier (Right), which has pulled a
long way back up the mountain, and Wellesley Glacier (left). Check the detail in the picture of
Wellesley Glacier and the reflections under Vassar Glacier..
And here are some seals, one more time.