Saturday, December 29, 2012

Antarctica Part 6 –Ice Bergs in the Land of the Midnight Sun

By the way, we are traveling in the land of the midnight sun. Living in the Northern Hemisphere, I always associated this phenomenon with the northern Arctic Circle, places like Alaska, Norway, and Greenland. It never occurred to me that the sun never sets for half of the year in Antarctica until this trip. In Ushuaia the sun set at 10:30 pm and rose at 4:00 am. In Antarctica, it never set. I would wake up at 3:00, 4:00, 5:00 in the morning and look out my cabin window. It was as bright as day outside! I was very confused as to the directions east and west, since I am used to looking for the sun near the horizon. That strategy did not work here! The sun did move around in a circle in the sky and thus cast shadows on the mountains, hills and icebergs. I will talk about that more as I describe the majestic scenery.
               I learned that there are two kinds of ice bergs, sea ice and pack ice. The sea ice bergs are actually frozen sea water and contain salt. They are distinctly flat and usually all white. They thaw out every year and refreeze in the winter.  The pack ice is what accumulates onto glaciers on the land as snow falls. They are made of fresh water. We learned that Antarctica contains 90 percent of the world’s ice and the ice can be as deep as one mile.  Pack ice bergs are calved from the glaciers at the water’s edge. Depending on the height and width of the glacier, they can be very tall and expansive, with a variety of shapes. Their tops can be asymmetrical jagged peaks or white slopes.
               What makes the pack ice bergs turn blue? All ice contains air molecules. When the ice builds up on the top, the pressure becomes so great that it squeezes the air out of the ice on the bottom. I was told that if you are very quiet, sometimes you can hear the ice making a popping sound as the air is squeezed out. It’s as if the ice bergs are alive and constantly changing. The black ice is the densest; all of the air has been squeezed out and it appears black in color. I was told by the guide that it is the same principle as black ice on a frozen road up north. There it is dangerous because it is the same color as the road and the drivers cannot see it. Thus their cars skid and crash when they drive over it.
We cruised the water in our zodiac boats to look at ice bergs and the cruises usually lasted from one to two hours. The first two pictures show pack ice bergs; note that the blue green water color marks the part of the ice berg under the water, the largest part. Note also that in the second picture you can see the ship parked on the right side of the berg. We thought this photo was funny because it looks like the ship is stuck in the ice berg! Look how clear and blue the sky is in these pictures! These were taken in the morning. The third picture shows an ice berg with holes in it. You can see a tiny piece of floating ice through one of the holes. The fourth picture shows a flat sea ice berg and a pack ice berg. Look how dark the shadows are on the slope of the mountains on shore! This picture was taken in the afternoon. Al pointed out that the landscapes changed as the angle of the sun changed, adding even more beauty and variety to the spectacular scenery! The fifth picture shows two good examples of flat sea ice bergs. The sixth picture shows a rare black ice berg, the only one we saw on the trip! This picture was taken on a cloudy overcast day with no sun at all. Ergo the water is gray.
I want to add a note about the submerged ice bergs. Sometimes our zodiac boats would run over part of a submerged berg and we would hear a crunching sound. At times, aboard the large ship, we would hear the same crunching sound, only louder! But we were not afraid of sinking. Thank goodness the hulls of the ship and of the zodiacs were reinforced to cut through pieces of ice! So Al got to ride on an ice-breaker boat after all! He was a little disappointed when we first learned that we would be going on a luxury cruise ship. It was a new vessel for Quark Expeditions and they offered a 25% discount to book it! So I signed us up!

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