Know Your Glaciers: A Guide to Describing the Alaskan Ice
06/27/2012Back To Blog
Few sights are more spectacular on an Alaska tour than the glaciers at Kenai Fjords , Glacier Bay and Denali. Whether you plan to visit the glaciers by flightseeing, cruising or hiking, use this quick glossary to learn a few key phrases to impress your fellow travelers (and guides) with your knowledge of glaciology.
Types of Glaciers
According to the U.S. Geological Survey, there are thirteen types of glaciers, but you only need to know three to start describing Alaskan glaciers.
Calving glaciers like the Margerie and Hubbard Glaciers are named for the process of icebergs breaking off into the sea. The Malaspina Glacier is the largest Piedmont glacier in Alaska. Its iconic fan shape was formed as the glacier spread out into a plain after having been confined by a valley. In temperate glaciers such as the Matanuska and Burroughs glaciers, the temperature is moderate enough that for part of the year the glacier has both frozen and liquid sections.
More Words to Describe Glaciers
Lifecycle of Glaciers
Glacial formation is a story of freezing and melting. Accumulation is the addition of ice or snow. Ablation is the loss of ice or snow and downwasting is thinning due to melt.
The barren zone is an area at the edge of a glacier where the ice melted away recently enough that plants haven’t grown in. If you hear a fizzing sound like you just opened a soda, that is the Bergy Seltzer, and it happens when air of different pressures is released from the melting ice.
Glacial lakes and glacial streams can form on, in, and under glaciers. Streams surface under pressure as fountains. Look where you are walking lest you fall into a crevasse. Caused by the stress of movement, these cracks can be over 100 feet deep.
How Glaciers Shape Landscape
The relationship between rocks and ice is what makes the Alaskan landscape so spectacular. The mountain peaks poking out between glaciers are Nunataks. Parallel grooves left on land by rocks frozen into the glacier are striations. Rock flour, the fine sediment ground down by a glacier, gives the rivers their gorgeous range of colors.
Now that you have the words to de-ice any glacial conversation, what glacier will you visit first on your Alaskan adventure?