1c.Types of glacier

Question 1

Formation of ice

Answer 1

• Snow remains frozen throughout the year (firn), fresh snow falls on the old snow
• Fresh snow has low density and traps air
• As more new snow falls, it compresses the layers of snow beneath, squeezing air out (more dense, turns into glacial ice)
• Takes 1000+ years, glacial ice is blue 100m deep (lack of oxygen)

-Diagenesis: compressing of snow to ice

Question 2

Ice sheets

Answer 2

• 50,000^2 km
• Ice flows out from center
• Covered most of Europe during ice age
• Antarctic ice sheet: 13.6 million^2 km, 30 million^3km over 4700m deep

Question 3

Valley glaciers (alpine glacier)

Answer 3

• Glaciers confined by valley sides
• Outlet glaciers from ice sheets or fed by ice from corrie glaciers
• 10 to 30km in length
• Steep sides

Question 4

Ice Cap

Answer 4

• 50,000^2km>

- Huge flattened some shape mass of ice

Question 5

Ice shelf

Answer 5

• Extension of ice sheets over sea
• 1km thick
• 500m thick at edge

Question 6

Piedmont glacier

Answer 6

-Large lobs of ice formed when glaciers spread out over plains