Glaciers and frozen water

What we will learn

What is a glacier? What is an iceberg? How do glaciers shape the land? How do glaciers affect the weather

and the oceans? Should glaciers be melting? Have there always been glaciers?

Glaciers

A glacier is a large mass of snow and ice.

There are different types of glaciers. Glaciers can and do move. Glaciers grow and recede. Glaciers alter the land underneath

them.

Types of Glaciers

Valley Glacier Continental Ice Sheets Ice Caps Piedmont Glaciers

– A single glacier may have stages of multiple types

Valley Glacier•A valley glacier or alpine glacier travels between two mountain ridges. Over time, it will deepen, widen, and straighten the valley.

Examples of valley glaciers include:•Muldrow, Hubbard, and Barry glaciers in Alaska•Rhone Glacier in Switzerland

Continental Ice Sheet Glacier•There are two continental ice sheets. Combined they cover almost 10% of the Earth’s land.•If they both melted, the oceans would rise by hundreds of feet.

Examples:•Antarctica•Greenland

Ice Cap•Ice cap glaciers cover islands at high latitudes and mountain tops at high elevations.

•Examples:•Iceland•Baffin, Devon, and other Arctic islands•Kilamanjaro in Africa (maybe?)

Piedmont Glacier•When a valley glacier spreads out at the base of steep mountains, it may spread out to form a piedmont glacier.

•Examples:•Malaspina in Alaska

Tidewater Glacier•Glaciers that terminate at sea are called tidewater glaciers.•Here, the zone of wastage is found where the glacier meets the water.•The glacier calves (breaks off in chunks) into the sea.

Examples:•Hubbard Glacier- St Elias National Park, Alaska.•Tyndall Glacier- St. Elias National Park, Alaska

Calving

Extreme Ice Survey

The Extreme Ice Survey is a project funded by National Geographic, NASA, and NSF. They monitor the overall health of the worlds glaciers.– http://www.extremeicesurvey.org/

EIS on Google Earth– http://www.extremeicesurvey.org/files/84791238080472

Extreme-Ice-Survey.kml

Extreme Ice

PBS Special– http://video.pbs.org/video/1108763899/