Glaciers
Today more than _____ of the world is covered by glacial ice.
1/10
We usually only see about _____ percent of an iceberg above water.
10
Greenland
13,800 ft. thick and 708,000 square miles
Glacier
a large mass of compacted ice that flows under the influence of gravity
2.
streams carry material as it melts
About 18,000 years ago ____ of the earth was covered by glaciers.
1/3
Antarctica
5.5 million square miles, 15,700 feet thick, and 90% ice and 77% fresh water
If all the land ice on earth melted it would raise the sea level by ____ meters.
70
3. Icebergs
80% to 90% of the iceberg is below the surface of the water
1. Icebergs
Calving: when an ice block breaks off a glacier with a terminus at seaside
The lakes and rich soil of the American _______.
Mid-West
The Fiords and peaks of ____________.
Patagonia
and ________ valley
Yosemitia
By studying ______ trapped in the ice, researchers can reveal the history of the earth's climate.
air
Continental
an ice sheet that covers a large area
2. Icebergs
approximately 20,000 created each year and 150 are hazards to ships
Snowfields
areas where winter snow fails to melt completely in the summer> this is where glaciers are formed
4. Cirques
basin formed at the top of glaciers as rock is scoured out when the ice begins to move downward
Icebergs are formed by glacial ice cracking off and this is called _____.
calving
We can see the effects of glaciers long after they have _____.
disappeared
A glacier begins to form when snow _____ faster than it ______.
fall, melts
Icebergs
floating glacial ice
7. Fiord
flooded inlet created when a glacier erodes its valley floor below sea level
6. Horn
formed when a mountain peak is surrounded by glaciers and multiple cirques
Geologists believe that for much of the last 3 million years _____ covered much of the North east Landscape of the United States.
glaciers
1.
glaciers deposited debris 3 ways > 3 facts
Firn
granular ice formed by compresses snowfield, snow that has built up for years
2. Polishing
ice and rock scrape rock under the glacier to a smooth finish
5. Tarn
lake that remains in a cirque after a glacier dissolves
5. Icebergs
largest ever > 3,700 square miles in area, 164 feet above the surface, and 1,640 feet thick. 7 times larger than Jamaica.
Terminus
leading edge of the glacier, the location where the ice melts faster than it can be replaced, or where it falls into the sea
Hanging Valleys
many these leave waterfalls after the glacier recedes> example; bridal veil falls in Yosemite
1.
material drops under it as it melts
3.
material is piled up on its edges and terminus as the ice pushes it
2. Lateral
material that is deposited on the side of the glacier
1. Terminal
material that the glacier pushed in front of it
3. Outwash Plain
melt water streams deposit sand and gravel from the glacier
Valley/ Alpine
narrow river of ice in a high valley > the most common type of glacier
2. Moraines
ridges of material deposited by glaciers > 3 types
6.
rivers cut a V shape and glaciers cut U shapes
The bottom layer of a glacier moves ______ than the top.
slower
3.
small side glaciers enter a larger glacier from higher elevations and carve out hanging valleys
3.
speed is at its greatest at the center and slower at the bottom than the edges because of friction
Wastage Zone
the area where the glacier's annual melting just exceeds
Flow Zone
the bottom portion of the glacier where the ice is like plastic and moves unevenly
The debris left behind in the sandy bluffs of cape cod was transported by glaciers from _______.
the ice age
Snowline
the lower edge of a snow field
1. Plucking
the process of ice tearing out chunks of rocks
Fracture Zone
top portion of the glacier that is brittle and cracks because of the uneven movement
4. Icebergs
water salinity is the factor of how much of the top is seen > higher salinity = more of the top is seen as it is floating out of water
3. Medial
when 2 glaciers merge their lateral moraines creating a center debris pile
Piedmont
when a valley glaciers combine and spread out over a plain