Week 2
10 July 2006

Water, Ice, and Snow- How much?

This week’s hot topics are a bit on the cool side. Antarctica holds lots of water and has lots of ice; however, its annual snowfall may surprise you.

Ninety percent of the world’s ice is found in Antarctica, about 30 million km3. This is about 70-85% of the earth’s fresh water.

Ice, icebergs, and other ice formations are prominent features of the Antarctic zone. The Antarctic continent is 99.77% covered with ice. The ice in Antarctica is up to 4776 meters thick, although the mean ice depth is 2496 meters.

Conversions: At its deepest point, is the Antarctic ice deeper than a mile? Give your answer in feet and in miles.

The world’s largest glacier, the Lambert Glacier is found in East Antarctica. It flows for over 400 km.

Concepts: How is a glacier different from ice or snow?

Need some ice? You probably wouldn’t want sea ice in your soda, but try this anyway.

Tabular iceberg - Photo by Vladimir Repin	Pancake Ice - Photo by Scott Dunaway

Matching: See if you can match the name of the ice with its description.

1.	Select One A. Anchor Ice B. Growler C. Fast Ice D. Iceberg E. Ice Shelf F. Pancake Ice G. Ice Cube	Pieces of floating glacier, too small to be an iceberg. They float low in the water, barely showing above the surface. They can be dangerous because they are difficult to detect on ship’s radar. (Hint: think about unfriendly dogs.)
2.	Select One A. Anchor Ice B. Growler C. Fast Ice D. Iceberg E. Ice Shelf F. Pancake Ice G. Ice Cube	A sheet of very thick, generally floating ice attached to land, usually with an ice cliff or barrier at the front
3.	Select One A. Anchor Ice B. Growler C. Fast Ice D. Iceberg E. Ice Shelf F. Pancake Ice G. Ice Cube	Submerged ice attached to the seabed (Hint: what can ships use to attach to the ocean floor?)
4.	Select One A. Anchor Ice B. Growler C. Fast Ice D. Iceberg E. Ice Shelf F. Pancake Ice G. Ice Cube	Thicker cakes of new ice that collide with each other producing turned up edges
5.	Select One A. Anchor Ice B. Growler C. Fast Ice D. Iceberg E. Ice Shelf F. Pancake Ice G. Ice Cube	A large mass of floating ice that has broken away from a glacier or ice shelf
6.	Select One A. Anchor Ice B. Growler C. Fast Ice D. Iceberg E. Ice Shelf F. Pancake Ice G. Ice Cube	Sea ice attached to the shore
See answers below

Icebergs – Nemesis of the Titanic

Find the origin of the word “nemesis.”

Most icebergs last 4-6 years and can take several years to melt. Icebergs differ in their shapes due to the actions of waves, currents, and upwellings. The blues and greens of the ice are changed by the light conditions.

Fom a Rig Manager for Global Marine Drilling in St. Johns, Newfoundland. They estimated the weight at 300,000,000 tons.	Iceberg off King George Is. - Photo by Marina Frants

Several major icebergs formed in 2000. One, calved from the Ross Ice Shelf was approximately 295 km long by 37 km wide.

Comparison: Was the length of that iceberg greater than the width of the country of Chile?

 

Snow

It snows much less in Antarctica than most people think. Much of the interior of the continent receives less than 10 cm annually; only coastal areas and parts of Western Antarctica exceed 30cm per year. However, blizzards redistribute the snow and can create drifts capable of burying buildings.

Compare the snowfall in your area (or in the nearest area where it snows seasonally) to the snowfall in the interior of Antarctica. Which area gets more snow?

 

Snow on the NB Palmer