And this is their story…..

“Fast Times at Glacial High”

ERIC MARCH

Glaciers

What is a glacier?

• A glacier is a massive, long-lasting, moving mass of compacted snow and ice.

• Glaciers can only form on land, wherever the amount of snow that falls in winter exceeds the amount that melts in summer.

• There are two types of glaciers…

Alpine Glaciers• Form on mountains because mountains usually

have deep winter snowfall and the summers are short and cool.

• This type exists on every continent, EVEN on the EQUATOR in Africa on Mount Kenya and in South America on Mount Cayambe.

Mt. Kenya

Continental Glaciers

Miscellaneous Info

• Did you know that… • Glaciers store about 75% of the world's freshwater. • Glacierized areas cover more than 15,000,000 square

kilometers of the Earth. • Glacier ice crystals can grow to be as large as baseballs. • Glacial ice often appears blue because ice absorbs all

other colors except blue; which is reflected. • Ice shelves may calve icebergs that are over 80

kilometers long. • Almost 90% of an iceberg is below water--only about

10% shows above water. • North America's longest glacier is the Bering Glacier in

Alaska, measuring 204 kilometers long.

Interesting Fact of the Day

• Byron Glacier• Located in Alaska, On

Mt. Alyeska• One hour south of

Anchorage• Receding fairly quickly

due to global warming• Tundra is slowly being

replaced by larger plants.

Glacial Movement

• All glaciers can be thought of as rivers…just really big, frozen rivers!

•Because all glaciers are moving, most at an average of 10 inches per day!

Glacial Movement

• Glaciers move two ways:

– Basal Slip

– Plastic Flow

Basal Slip

• The entire glacier slides over bedrock, much the same way that a bar of soap slides down a board

Plastic Flow

• The glacier deforms like a fluid as it moves downhill

Plastic Flow• The glacier deforms like a fluid as it moves

downhill

Glacial Movement

• Glaciers can move with both basal slip and plastic flow– Steep alpine glaciers will be mostly basal slip– Shallow continental glaciers will be mostly

plastic flow

Features of Moving Glaciers

• Glaciers flowing over bumps in the bedrock produce crevasses

Features of Moving Glaciers

Glacial Erosion

• Water freezes in gaps in the bedrock, freezes, and dislodges boulders that get swept up by the glacier and dragged along!