WAIS Divide, Antarctica, Jan. 11, 2010 — Drilling has been going very smoothly lately and we are averaging just over 30 meters of core a day. A round trip drill run at our current depth takes about 2 hours to complete, and typically produces an ice core that is ~3.2 meters long. We have been averaging ten runs per day, which corresponds to 32 meters of core, or about 365 years of snow accumulation (the record for the longest core so far is 3.482 meters!). We have finished packing the ice that will be shipped back to the U.S. this year and the last pallet is ready to be picked up. The rest of the ice drilled this season is being stored in the snow-walled basement of the arch. At the start of my shift today, we were at almost 2200 meters depth.
Today was a sunny day with very few clouds. One nice thing about sunny days is that ice crystals which form on the surface of the snow reflect the light and sparkle like diamonds. I have seen this many times in the northeast U.S. where I grew up, but not nearly as intensely as I have seen this effect here. I guess because almost everything is covered with ice crystals, it really feels like you are walking through a field of diamonds. Even better yet, sometimes you can actually see tiny ice crystals floating in the air. When the sunlight hits them, they also sparkle like floating diamonds above and all around you (sometimes called diamond dust). It almost makes you dizzy as it is hard to focus on all the tiny flashes moving so quickly in all directions.
I’m standing in front of the sun with a halo. Note the white dots above my head.
They look like dust on the camera lens but they are actually tiny ice crystals
(diamond dust) floating in the air and sparkling as they reflect
the light from the sun
[Photo credit: Robert Lee Hotz, The Wall Street Journal].
After dinner, I decided to take a walk. I wandered off across the ice sheet towards the white endless nothing. I put town behind me and out of sight, and headed out into my mystical world of floating, sparkling diamonds. Antarctica can be a magical place.
Antarctic Factoid
A sun dog is an atmospheric phenomenon that creates bright spots of light in the sky, sometimes on a luminous ring or halo on either side of the sun. They sometimes form during very cold weather, when the sun is low in the sky, from ice crystals (diamond dust) drifting in the air. Light is reflected and refracted by the ice crystals and may split up into colors due to dispersion. The crystals behave like prisms and mirrors, refracting and reflecting sunlight between their faces. Sun dogs and halos are red colored at the side nearest the sun and grade through oranges to blue.
Antarctic Factoid
Fog bows can be seen on foggy days when the sun is still able to shine through the fog. Fog bows are similar to rainbows, except that they appear white and have no color. The lack of color is caused by the smaller water droplets, smaller than
0.05 mm, that create the fog.
Halo around the sun. Sun dogs (bright spots of light) can be see on either side
of the sun and above the sun. It is hard to see but the sun dog above
the sun is curving in the opposite direction of the halo (away from the sun).
This is my best attempt at photographing a fog bow.
About half of the fog bow can be seen arching over tent city.
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