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PICTURE AT THE TOP OF THE PAGE: I took this on January 16, 2009 in a fairly narrow strait called the
Lemaire Channel. It is not far from the Gerlache Strait and Anvers Island, and all of these are a little way
down the west side of the Antarctic Peninsula. The flat wall in the picture is the front of a lot of glacier
ice with just a hint of blue ice showing. Click here or in the picture for a larger version, and click here for
a larger version with the colors somewhat enhanced in order to see the color better. There are also a
couple of humpback whales in this picture, or at least parts of them swimming in the foreground.
We are going to say more about blue ice in this gallery. See the bottom of the page for an explanation of
the color.
Here are two pictures of the same glacier front, but one is zoomed. I like the zoom lens. So you can
get in pretty close by looking at a large version of the picture on the right hand side. This spot in along
the mainland side of the Lemaire Channel, which is a fairly narrow passage about a mile wide at its
narrowest between the Antarctic mainland and Booth island.
This picture and the next two are Lemaire Channel
pictures. In some places the ice and/or snow surface
slopes smoothly down towards the water. But there are
also those steep walls with a hint of blue. Those are
places where icebergs have fallen off to slowly float away.
There are some very scenic, steep, bare rock slopes too.
I want to say that I cannot tell a lie, but I can
enhance a picture. However, since I want to
emphasize the blue glacier ice here, I am showing
these pictures without color enhancement. In the
broken walls, you can often see a hint of blue
anyway. These are pretty much the way the eye
sees them. In a few cases, the eye sees something
very blue, sometimes a hint of blue, sometimes not
even that.
In each case, there is an ENHANCED VERSION link
to bring out more color.
There is more likely to be evidence of blue ice
where it has been broken in some way or maybe
melted thus exposing the deeper ice. For
example, look at the holes in the picture to the
left.
On an unbroken surface or an older surface, the
color is more likely to be white.
Besides a glacier front and blue holes, this one
shows that civilization is not entirely absent in
Antarctica, though it is precarious. This is part of
an abandoned research station belonging to Argentina
that has been taken over by penguins, not seen
here. I have some penguin pictures in another
gallery (to be uploaded soon).
Something else here, and in most of the other
pictures, is bare rock right at the coast. Check
Gallery 4 for more on that.
Starting with the picture with the building just above,
the remaining pictures in this gallery are in some of
the bays off of the Gerlache Strait. This cruise ship,
called the Marco Polo, gives a sense of scale to the
glacier fronts. Although I am not familiar with the
ship, I think it is about the equivalent of a ten story
building from the waterline to the top of the stack. I
think this because of counting the rows of portholes
and projecting up and down.
While checking a couple more pictures through fog, lets
think about where the blue color comes from. Glacier
ice is made out of snow that has been highly compressed
by the great weight of more snow on top of it. This
squeezes out much of the air and makes larger ice
crystals than in ordinary ice such as ice cubes and the
ice you slip on in your driveway.
The sunlight that falls on ice is nearly white and consists
of a mixture of all colors. But ice tends to absorb
colors other than blue, so when the light finally gets out
of it, if there is enough ice, it looks blue. With
ordinary ice or snow, the incoming light reflects off of
the many crystal boundaries or small air pockets so
quickly that it never gets to go through enough ice.
With glacier ice, there are far fewer reflecting
surfaces, so the light can travel through enough ice to
make the exiting light look blue.
But the surface of a glacier usually looks white. For one
thing, it might be ordinary snow that has fallen on the
glacier recently. Or it might be ice that never felt
enough weight on top of it to compress it into glacier ice.
And the surface ice tends to revert to ordinary ice
anyway. So you only see blue if, through breaking or
melting, the internal glacier ice is exposed.
You also can see blue ice when there has been melting
and re-freezing, because that often destroys enough of
those internal reflecting surfaces.
One more thing: It is the water molecules that compose the ice that absorb the colors other than
blue. If you delve into molecular structure in enough detail, you find that this is just the way these
molecules behave. They don't give up the same kind of light again, either. Instead, they just heat
up -- a very, very little bit. Water molecules do this in liquid water, too. So light that has passed
through a lot of liquid water looks blue as well. You knew that, didn't you?
See Gallery 6 for more about the blue color as seen in icebergs.
And HERE IS a site with some great pictures of icebergs with blue ice and a more detailed scientific
explanation for the blue color.