Polar Ice | Antarctica in Context

The Earth’s polar regions are not familiar places to most people. Flat maps often show them as a distorted place at the top and bottom. Globes need to be examined more closely to see them. The support of the globe is in the way. My goal is to help make the polar regions more familiar, to point out features, and to identify things important to climate research. There will be three posts in the Polar Ice series. This post has a focus on the Antarctic. The next one will focus on the Arctic. The third will compare the Arctic and Antarctic regions noting important changes related to climate change.

Antarctica is 1.4 times larger in area than the United States. A small part of Antarctica, the size of Denmark, is snow and ice free. The 3300 km Transantarctic Mountain Range divides Antarctica in East and West parts. Starting from the South Pole, travel along the Prime Meridian to the north or top of the image, you will eventually pass through Greenwich, England. Travel along the 90˚W meridian and you will pass through the Galapagos Islands, Central America, and up the Mississippi River valley through St. Louis, Missouri. Travel the 90˚E meridian and pass through the Indian Ocean, east of India, China, western Mongolia, and Russia. The 180˚ meridian passes through the Pacific Ocean, goes west of Hawaii, and traverses the east Siberian region.

British Antarctic Survey

British Antarctic Survey | Click to embiggen

The continent is classified as a desert with less than 10″ (254 mm) of equivalent liquid from the snowfall. The interior gets less than 2″ (50 mm). Coastal areas can receive as much as 8″ (200 mm) of precipitation. None of the snow melts and has built up into a layer averaging over 1800 meters thick. The maximum is 4776 m (3 miles). Because of the tremendous weight of snow and ice, it tends to flow toward lower elevation and to the sea.

The ice flows occur at nearly all of the perimeter of Antarctica to some relatively small scale. Two places have especially large regions where these flows create shelves of thick ice out over the water. They are the Ross and the Ronne ice shelves seen in the map above. The following cross-sectional diagram shows how they extend and calve off icebergs into the sea. Icebergs are much more submerged than indicated in the diagram.

The NASA Scientific Visualization Studio released this animation showing the ice flow and underlying bedrock beneath the ice sheet.

No single government rules Antarctica. Eight nations claim some territory. There are 29 nations which have research stations.

Wikimedia Commons | Click to embiggen

References

http://lima.usgs.gov/documents/Antarctica_in_context.pdf

http://lima.usgs.gov/ A zoomable map of the Antarctic from years of Landsat imagery.

http://lima.usgs.gov/documents/LIMA_overview_map.pdf

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18 thoughts on “Polar Ice | Antarctica in Context

  1. The work being done at the research stations in Antarctica is fascinating, especially Concordia Station at Dome C. I can’t image what it must be like for researchers who winter-over at the facilities. The closest I’ve been is hiking the Tasmanian-Antarctic gateway…in winter. Absolutely beautiful! 🙂 I was also lucky enough to visit the Aurora Australis icebreaker while it was docked in Hobart, very cool!

    Looking forward to your series!

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  2. Fascinating facts Jim. Martin Bailey, a well known photographer, used to have expeditions there. His landscapes with icebergs were amazing due to the translucency of the blue sky through the ice and the ocean. Some landscape photographers love this effect.

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      • No, but I will be on the lookout. I saw some of the images and yes, it’s that turquoise and emerald colors that glaciers radiate with the sun, that landscape photographers love. Thanks for recommending the film. Sometimes I tend to ignore environmental films because they remind me of how much damage has been done to the planet, and animals constantly losing habitats…

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      • The film both shows the beauty of the ice and the terrible loss of it. Some tears welled up on me for both reasons. You will like it. If you have Netflix, it is on there. Or, a library may have a DVD copy to loan.

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  3. You’ve reminded me of a riddle I remember from childhood that went something like this: “I walk north a mile, then west a mile, then south a mile, and I find myself back at the place I started out from. Where am I?” The only place on earth where that’s possible is the South Pole.

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