Saturday, December 6, 2014

An Aquatic Adventure

When I was in McMurdo, I visited the “Ob Tube.”  This is a metal tube drilled through the ice with what is best described as an observation pod at the bottom of the laddered tube just under the ice.  I found a photo with a scuba diver that for scale shows what this looks like and how large it is- pretty cramped.  You sit curled up in the upper-part of that structure with the windows.
The pod has a 19th century Captain Nemo feel while the top on the surface looks like one of the pipes in Super Mario Brothers.  Climbing down the tube gives you a sense of how thick the ice is around 100 yards from the shore — about 20 feet.

Possibly the coolest things you see down there are ice stalactites hanging from the bottom surface of the ice.  I took the photo on the left.  I’m told that these things form when fresh-water hits the ice.  Freshwater freezes at a higher temperature than the surrounding salt-water and as more water flows down these small holes, it adds to the structure, freezing at the end.

The surface of the ice is barren and dead, but under the ice, Antarctica looks pretty lush.  The ice in my photo (left) is covered in some sort of sea algae plant.  The water was filled with tiny fish and one of my friends saw a 6-foot long jelly-fish down there.  In the photo above, the small flecks that you see are actually little tiny fish.  Of course, the algae on the ice limits the sunlight-- hence the poor photo quality.  Had I been there a few weeks earlier, I would have seen something like what my colleague photographed at right above.

Lastly, you could hear seals talking down there, making sci-fi torpedo-like noises.  Listen to the audio above.  I borrowed the photos for the slide-show from this blog where the photos were taken in a different ob-tube installed 15 miles from McMurdo.

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