1. Ch. 15 Glaciers

2. How are a river and glacier the SAME, DIFFERENT?

3. Compare a River to a Glacier
Fast flow
Liquid: rain or snow
<1% of hydrosphere
Anywhere on earth
warm climates
Living things
Low elevation
People can pollute
Slow flow
Solid ice (firn)
10% of hydrosphere
Poles or high elevations
Cold climates (year-round)
No living things in them
Larger in size
H2O hydrosphere
Fresh water
Gravity pulls
Transport materials
Erodes valleys
Tributaries
Change over time
Level/size changes

4. The hydrologic cycle

5. The Earth’s Water Cycle
Salt water
Fresh water

6. So What is a Glacier?
A thick mass of ice that forms over land from the compaction and recrystallization of SNOW and shows evidence of past or present flow

7. Glaciers Facts Cover 10% of Earth’s land
75% of earth’s FRESH water!!!!!!!!
Glaciers change land by eroding, transporting and moving huge amounts of sediment.
Glaciers are part of both the Water Cycle & Rock Cycle.

8. Parts of a Glacier Zone of wasteage snowline Melting, sublimation
Crevasses
snowline
Melting, sublimation
Ice front
icebergs

9. What is the Snowline (Equilibrium line)
Definition: (page 318)
The lowest elevation with permanent snow occurs in the summer

10. Where is Earth’s largest glacier...

11. ????????
Can glaciers form in tropical regions?

12. Where glaciers can form…
North and south poles.
Cold climate year-round
High elevations in mountains.
Exist on all continents except Australia.

13. Mt. Kilimanjaro, Africa Latitude: 3
Mt. Kilimanjaro, Africa Latitude: 3.07 degrees South of Equator Elevation: 19,335 feet

14. Elevation of the snowline (glaciers formation) decreases as the latitude increases Can Illinois have Glaciers?
Pg. 318

15. Types of glaciers pg.318-19 Continental Alpine or Valley Where?
Size/shape?
How many?

16. Continental Glaciers
Covers large landmasses like Antarctica and Greenland.
Can be a mile thick in places.
Mostly circular or oval in shape
Spreads out in all directions
Also called an ice sheet
Some places the ice reaches the sea and can break off into icebergs.

17. Antarctica
Earth’s largest
continental glacier

18. In Continental Glaciers the weight of the accumulating snow pushes the glacier out in all directions like pancake batter

19. Greenland ice sheet

21. Valley glaciers
hundreds of small glaciers found high in the mountains where streams once ran.
Also called “Alpine” glaciers.
They flow slowly downhill between valley walls.
They also have tributaries like streams or rivers.

22. Piedmont
When a valley glacier emerges from the confining walls of a mountain valley and spread out into broad sheets.
Alluvial fan of sediment

23. As glaciers move over bumps and uneven land, crevasses form
They form in the brittle, top as 50 meters!

24. Crevasses Fissures or cracks that form across the width of a glacier.

25. Calving Cows have calves, glaciers calve icebergs
Calving is when chunks of ice break off at the terminus, or end, of a glacier.

26. Ross Ice Shelf

27. Ross Ice Shelf, Antarctica is a huge ice sheet “floating” out on top of the more dense Pacific Ocean salt water

29. If a glacier is NOT a frozen river, NOT a pile of snow
What is a glacier made of and how does it form?

30. Anatomy of a glacier (snow) In a glacial valley Snow line
Ice front /snout

31. (90% air spaces)

32. As snow layers pile-up year after year,
What happens to air space and density of the snow?

33. So how do you make a glacier?
More SNOW falls in the winter
than melts in the summer.
2. Layers of snow accumulate year
after year (above the snowline)
The snow COMPACTS and RE-CRYSTALIZES into FIRN
FIRN turns into solid Glacial Ice
Then… the mass moves, slowly
down hill due to gravity.

34. On a sheet of paper: True or False?
_____ 1. Glaciers are only at the north and south poles.
_____ 2. A glacier is solid ice.
_____3. Antarctica is covered by a glacier.
_____4. There could never be a glacier at the equator.
_____5. All glaciers move.
_____6. Glaciers flatten the land.
_____7. When glaciers melt they back up.
_____8. Glaciers can carve out valleys.
_____9. The Great Lakes were formed by glaciers
_____ 10. There has been one Ice Age .