Chapter 17

Question 1

Glacier

Answer 1

A glacier is a mass of ice on the land surface that is a result of snow accumulation.

Question 2

Where do glaciers form

Answer 2

They form where it is wet (snow) and cold - at high elevation and high latitude.

Question 3

Formation of glacial ice

Answer 3

fresh snow -> Ice pellet (firn) -> solid ice

3 factors:

• time
• compaction
• melting + freezing

Question 4

Firn

Answer 4

Ice pellet

Question 5

Two types of glaciers

Answer 5

1. Alpine

2. Continental

Question 6

Alpine glaciers

Answer 6

Form at high elevation

Question 7

Continental glaciers

Answer 7

Continental glaciers form at high latitude

Question 8

zone of accumulation (see diagram)

Answer 8

higher part of the glacier (above firn line) where there is a net increase in snow and ice

Question 9

zone of ablation (see diagram)

Answer 9

lower part of the glacier (below firn line) where there is a net loss of snow and ice

Question 10

Glacier budget

Answer 10

Depending upon the amounts of accumulation and ablation the glacier will either advance (positive budget) or retreat (negative budget)

Regardless of whether the budget is positive or negative all glaciers reach an elevation or a latitude beyond which it can go no further

At this point all the ice melts.

Also, regardless of what the glacier budget is, gravity always pulls ice downhill, explaining why glacial ice persists below the snow line.

this is important because ice advances as a solid and retreats as a liquid.

Question 11

“Movement of ice in a glacier is very much like ______________” (see 3 diagrams)

Answer 11

Water in a river. Ice flows slowest closest to the bed rock and the sides and flow fastest towards the surface and middle of the flow.

The flow of ice is controlled by friction.