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WEATHERED ICEBERGS ANTARCTIC SOUND Gallery 6
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PICTURE AT THE TOP OF THE PAGE: Here is a spot that is sometimes called Iceberg Alley but is actually named the Antarctic Sound. It is a relatively small expanse of water just off the end of the Antarctic Peninsula - between that peninsula and some islands such as Joinville Island and Dundee Island. Because it is in an ocean current that can carry icebergs from where they break off of glaciers and ice shelves farther south, it is visited by even more icebergs than tourists -- I think. They can take on just about every imaginable shape after years of weathering. And that is just the icebergs, not the tourists -- well, not most of the tourists.
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AND ANOTHER THING OR TWO...
Icebergs are not the same thing as sea ice. Sea ice is formed when it gets so cold that the surface of the
sea freezes into a relatively thin layer of ice or thin patches of ice. This happens every winter in far
northern and far southern latitudes. Similar ice forms on lakes and rivers during cold, winter weather.
Ships, which find icebergs very disagreeable, can't navigate through sea ice either, which is why cruises to
the Antarctic are scheduled for the summer. We didn't see any sea ice on this trip, but that is just because
we avoided areas where it was still around. HERE ARE several pictures of icebergs in sea ice, where they can
become stuck just like a ship -- all from the International Ice Patrol.
GO HERE for a set of 15 images at Wikimedia Commons showing the same iceberg over almost a month near
Greenland. What is really interesting about this is watching the berg change shape due to melting, calving,
and weathering. It eventually becomes grounded near a harbor entrance.
HERE IS an iceberg article from NASA's Goddard Space Flight Center pointing out, among many other things,
that most northern icebergs come from the Greenland coast and take 2 or 3 years to reach Newfoundland.
After that, they don't usually last too much longer, but they have occasionally been seen as far south as
Bermuda.
THIS IS another page (in www.solcomhouse.com) devoted to icebergs, both northern and southern. Some of
the material is from the US Coast Guard's International Ice Patrol, some from NASA, some from NOAA's
National Ice Center. The Antarctic section starts about two thirds of the way down the long page, but much
of what it says about Arctic bergs, such as classifications (bergy bits, growlers, etc) applies in the Antarctic
as well. So does the discussion of how much of the berg is above water. Especially see the video of the
collapsing iceberg off of Labrador, also around two thirds the way down! One caution: there is a spectacular
picture combining the above and below water parts of a berg in the section on how much is underwater. I have
seen that picture before, and it is actually a composite of three different images. I don't think anyone could
get all of that in one image with the camera above the water line.



This place had no trouble living up to its "Iceberg Alley" name. Here are three pictures approaching a
field of icebergs, and that is only one of several such fields. You can see icebergs of a variety of shapes
right here, and this didn't come close to all the shapes we saw. I came partly to see icebergs, and I was
just hopping around like an idiot taking picture after picture and staring at berg after berg.
This is the truth: I didn't think the word "Titanic" even once while we were zooming around those bergs,
although I did think of it later that evening after we had left that area. The bridge crew was good at
missing them and still giving us a great view.
These pictures, especially the one on the right, show a problem I had. Notice the nearest berg is
overexposed while other parts of the pictures are too dark. Way too much contrast within the picture.
You can use the computer to cut the contrast down, but that makes them look funny. In most of the
pictures below, I cut the brightness down to bring out details of the icebergs. It makes the water look too
dark, but oh, well. Look below for many strange, weathered shapes:
On the right, the berg in the background is the same one that is at the top of the page. That is a volcanic island called Paulet Island in the background.
These things calve from glaciers and ice shelves (that is, fall off of them). Then they can last anywhere from 2 or 3 years to more than 20 years. It mostly depends on how long they hang around in the cold waters near Antarctica. Once they drift into warmer water north of Elephant Island, they are toast.
Weathering is caused partly by wind, partly by melting, partly by water, all leading to calving of the icebergs themselves (they fall to pieces). I didn't get to see calving, but GO HERE and HERE for calving glaciers I saw in Alaska.
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Full disclosure: These two pictures represent my preconceived notion of what an iceberg should look like.
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Maybe I have seen too many like these in movies. At least a few looked like this.
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Just above are three pictures of the same iceberg which, I think, looks vaguely like a ship. There in the
middle is the whole thing. On the left is what I somewhat ignorantly am calling the front, and on the right is
the back. Notice, on the "front" that the waves have worn a smooth groove at the waterline.
Of course, an iceberg doesn't really have a front and back and if it did, that would change as pieces wore
off or fell off. But there are waves breaking over the "front" and the "back" seems to have a wake. Think
about that. Icebergs drift with the current. They shouldn't leave a wake if they are keeping up with a
current.
What is probably happening is that this berg isn't going anywhere. Icebergs are deep enough underwater,
and the Antarctic Sound has many shallow spots, so bergs drift in and plow into the bottom. Then they get
stuck in place -- which is called being "grounded" -- until enough melts so they can no longer reach the
bottom. Then they drift away. Meanwhile, the current flows past the grounded berg, and that leaves a
wake.
I don't know what to call the one to the left of this picture. A
mushroom? A hat? The larger one in the picture seems to have stripes.
They are probably left over from the snowfall that produced the ice that
later broke away to become the iceberg. Dust can collect on the snow.
Or some kind of pollution from 1000's of miles away. Or algae from the
seawater. Or rocks scooped up by the original glacier. Or stripes of ice
left over from summer melting and winter re-freezing of the snow. So
layers -- often annual ones -- end up in the bergs. That helps tell the
history of the icebergs.
Here is another one of those hats -- or bergs with ridges -- or whatever.
Look at the detail around the edge of the ridge in the enlarged version of
the picture. (Click the picture -- remember?)
This one has a serious stripe of some kind. If these stripes started out
as stuff on top of a snowfall, then they should be horizontal, but this one
certainly isn't. Neither are many others. What happens is that icebergs
melt and weather unevenly so that the weight shifts. Then they tilt and
roll and sometimes roll all the way over. So what was once horizontal is
now something else.
Speaking of waves breaking over icebergs, which I was doing
up above a bit, and which I could have done while describing
the picture with the stripe, we saw plenty of that in the
Antarctic Sound.
In fact, we had a couple of unexpected episodes of high
winds. They didn't last very long, but they were exciting
enough that I am making a separate gallery about them. (I
haven't made it yet, but stay tuned.)
In the meantime, here are a few more pictures of bergs with
waves -- some of which are breaking over the bergs.
I made a few videos, too, on this trip, and some of them are
of icebergs in rough water. GO HERE for one of these on
YouTube. Notice that the foreground berg is just zooming
past with waves all over it. Some of the motion is due to the
ship moving past it, but notice also that there are several
bergs just behind it that are not moving at all. I assume they
have been unlucky enough to hit a shallow spot and become
grounded.
Another, similar one that I put on YouTube is HERE. This
time it is a smaller berg, but it sure rocks back and forth.
Notice the patches of blue color in the one to the right, the
one just above it, and in some of the others. That is not too
surprising since the glaciers they come from have blue ice.
But the blue is usually buried under snow, ice that never
became glacier ice, or ice that reverted to ordinary ice. But
you can see the blue color in some places where the ice is
melted or otherwise weathered down to actual glacier ice. (I
have enhanced the color a bit but didn't add any. There was
really blue color.) See Gallery 3 for more on blue glacier ice.
Those smooth parts of icebergs above, to the left, and below might have
been under water at some time in the past. Icebergs do tend to lose
their balance and roll over. That happens because of uneven melting and
weathering. Anyway, the underwater part of an iceberg seems to take
on a fairly smooth appearance -- something about the way the water
melts into it. Of course, weathering by wind can't reach it when it is
underwater.
From this angle, at least, this one looks like a bell. I have to admit
that this was a whirlwind trip, and we repeatedly sailed past sights that
I wanted to study for hours. There was no choice, of course. The ship
had to keep its schedule. I heard during the trip and I have checked it
out since that icebergs that have rolled over tend to have this sort of
smooth appearance after the roll. But I can't say for sure which bergs
actually rolled recently. All of these to the left and the one above near
Rosamel Island look like they have such a history.
They tell me that you don't want to be very close to one that is rolling.
They make big waves and throw a lot of ice around. But here is a great
video taken up close. I never saw it happen. But some other people
have and have left their videos on YouTube. Check THIS ONE out. It
shows the event more than once, and you get to see the rough,
weathered top disintegrating as it rolls, the wave being sent out, and
the smooth ice initially below water finally resting on top. It seems that
it either broke apart and each part rolled separately, or two nearby
bergs rolled one after the other.
ANOTHER ONE on YouTube is seen from a greater, safer, distance.
The former underside is more complicated but still has smooth areas.
Watch some of it break away after the roll and after they zoom in.









Here are more blue patches
on icebergs set against Paulet
Island in the top pictures.
(I am going to have a gallery on wind
and one on penguins - both featuring
more about Paulet island.)
Iceberg watchers are always
on the lookout for a totally
blue iceberg -- presumably
one with all of the snow and
ordinary ice somehow eaten
away exposing a glacier core.
They are very rare and
considered to be a delicacy,
although you shouldn't eat
one. We didn't see one.
HERE IS a story with pictures
from someone who did. And
HERE IS one seen by someone
from Alaska's Glacier Bay.
The two pictures just above are of the same iceberg -- with one end that looks like a fish with an open mouth!
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Blue stripes can be caused by the top of a snowfall melting and later refreezing into ice followed by more snow.
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In the middle of the Antarctic Sound is a small volcanic island called Rosamel Island. There it is on the
left -- relatively snow free compared with most of the land around here. I wonder if there might be
just a little volcanic heat in at least some parts of the island?? (I don't know the answer -- just
wondering. My map shows at least one undersea volcano very near here.) There is a patch of snow on
top in the zoomed picture in the center. You can see layers of something that have built up between
snowfall events. The iceberg just to the right of the island is the same one on the left several rows up
-- where I mentioned my preconceived iceberg notions. The berg just to the left of Rosamel Island is
seen in close up in the right-hand picture here. It has sort of an unusul smooth, rounded quality.