Module IX: Terrestrial Ice

Essential Question:
How are climate, terrestrial ice and Alaskan indigenous cultures all connected?

EXPLAIN: I travel out of state and out of the country a fair bit and whenever I tell someone I'm from Alaska they always ask about the cold. However, living in Southcentral, I have to get in my car to see glaciers. They're there- Matanuska Glacier, Exit Glacier, and even the seven glaciers that give their name to Seven Glaciers restaurant at Alyeska Resort. I just don't think about them much. I was extremely surprised to see the ratio of 1000 snow flakes in the world and discovering that Alaska could lay claim to one of those.

One of the places I'd like to travel to one day is Antarctica, just to see it. In the TD video Earth's Cryosphere: Antarctica, I learned that the frozen southern continent contains 70% of the world's fresh water. When the video stated that the clouds above Antarctica contain ice crystals and very little water, I thought of Denali being so tall it can create its own weather systems. The earth is full of unique ecosystems, but Antarctica is definitely the most desolate. It's scary to realize there are a growing number of melt ponds that weaken ice shelves and cause them to collapse. The fact that a 12,000 year old ice shelf could be loosened and collapse in only five weeks surely points to major climate change.

EXTEND: Antarctica is, on average, the coldest, windiest, and driest of all the continents. According to Wikipedia, the coldest temperature every recorded on earth was at the Russian Vostok Station in 1983. It was -128 degrees Fahrenheit! I've been in -35 degree Fahrenheit weather and that was cold enough for me- you can almost feel your eyes freeze when you first step outside.

Antarctica is colder than the Arctic because of its higher elevation and because it's not an ocean. Weather fronts don't penetrate into the interior of the continent, leaving it essentially a desert. And any precipitation is quickly pulled into glaciers. The Arctic Ocean is able to absorb some of the heat from the summer, making it the milder of the two poles. This is similar to how Anchorage has a milder climate than Fairbanks due to Anchorage's location on Cook Inlet.

EVALUATE: Students can certainly benefit from learning about Antarctica and its ecosystem and then comparing it to their Arctic home. The TD video, Melting Permafrost demonstrates how critical changing climate is to regions that depend on permafrost. Warmer summers and earlier springs are causing melting at both poles, resulting in melt ponds and collapsing ice shelves in the south and melting permafrost and collapsing houses in the north. There is evidence of this all over Alaska. When I was a tour guide, I would often point out a house in Fairbanks that has shifted so much until it now looks like it's ready to collapse in on itself. The house was built on permafrost that has since melted.

Image from Carbonica