Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

EAS > Lecture 17: Cryosphere 1 > Flashcards

Lecture 17: Cryosphere 1 Flashcards

1
Q

What is the Cryosphere?

A

The part of the earth’s surface that remain perennially frozen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How much of the earth’s surface is the cryosphere?

A

1/3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What comprises 2/3 of the cryosphere in terms of surface area?

A

Sea ice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What comprises 1-% of frozen ground and comprises 20% of the earth’s land surface?

A

Glaciers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What does the Cryosphere not include?

A

Areas that are temporarily covered by snow or ice, although these are important contributors to the hydrologic cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Where is the Cryosphere primarily located?

A

Near the north and south poles at higher elevations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How does the Albedo of snow affect surface temperatures?

A

It bounces sunlight back into space reducing surface temperatures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does the accumulation of snow that exceeds melting contribute to?

A

Formation of glaciers and ice caps

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the Snowline?

A

The boundary of areas that have snow year-round

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the location of the snow line controlled by?

A

Variation in thickness of winter snowpack and local topography

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What controls where the snowline is?

A
  • The amount of snow in that season
  • The summer temperatures
  • The position on the earth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the two ways that the elevation in snowline varies?

A
  • It is at lower elevation in polar areas where temperature is colder
  • It is lower in coastal areas where there is more moisture and thus more snow
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is Firn?

A

When existing snow is compacted by newer overlying snow and evaporation occurs at the points of snowflakes and moisture freezes between points forming the granular snow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How does Firn become ice?

A

It loses its interstitial air

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How is Ice affected by depth and time?

A

As depth and time increase the grains of ice become larger due to recrystallization as the fern merges together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are Glaciers?

A

Ice masses that flow under the influence of gravity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Where is the flow of glaciers fastest and why?

A

Flow is fastest at the center and slowest at the edges due to friction with the bed

18
Q

How does movement occur in warm glaciers?

A

Internal flow and sliding at the base

19
Q

What is movement like in cold glaciers?

A

They are frozen onto the underlying bedrock and therefore do not slide

20
Q

Why are Glaciers able to flow?

A

Because the ice crystals that comprise it deform under stress

21
Q

What does the continued deformation of ice crystals cause?

A

The alignment of ice crystals by internal creep where some ice crystals grow at the expense of others to form this structure

22
Q

What do warm (temperature) glaciers have at their base?

A

Meltwater that allows for flow along the bedrock

23
Q

What does the Meltwater typically cause physically of glaciers?

A

It causes glaciers to typically have a rounded terminus or toe

24
Q

Where do cold glaciers not flow?

A

At their base

25
Q

What kind of terminuses do Cold (polar) glaciers have?

A

Cliff terminuses

26
Q

What are regions of accumulation of glaciers?

A

Where mass is added

27
Q

What are regions of ablation of glaciers?

A

Where mass is lost

28
Q

What can Ablation of glaciers be caused by?

A

Melting, evaporation or the calving (the breaking of ice from the parent glacier)

29
Q

What is the relationship between accumulation and ablation in the different areas of a glacier?

A

Accumulation exceeds ablation in the upper part of a glacier and ablation exceeds accumulation in the lower part

30
Q

What is the Equilibrium line of a glacier?

A

The separation of an accumulation and an equilibrium line

31
Q

What is the overall ice mass balance of a glacier equal to?

A

Its accumulation minus ablation

32
Q

What is a receding glacier?

A

A glacier with negative mass balance

33
Q

What is Glacial Erosion?

A

When Glaciers erode bedrock at their base by freeze-thaw cycles at the physical base of the glacier, and physical abrasion and plucking of rock fragments from bedrock

34
Q

What are Chatter marks?

A

Crescent shapee gouges that can form as rock fragments are dragged across bedrock by a glaciers

35
Q

What are Striation?

A

Linear gouges and or scratches left in bedrock by glaciers as they move sand and rock fragments at their base

36
Q

What are U-shaped valleys?

A

Valleys with steep sides and broad, flat bottoms that are left by glaciers

37
Q

What usually feed into U-shaped valleys?

A

Smaller hanging valleys

38
Q

What are Arêtes?

A

Sharp edged ridges of glaciers

39
Q

What are Horns?

A

Pointed pyramidal peaks

40
Q

What are Cirques?

A

Bowl shaped valleys formed at a glaciers head

EAS (33 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions