Cryosphere

Question 1

Cryosphere

Answer 1

part of earth’s surface that remains frozen

Question 2

The cryosphere takes up approximately ___ of the surface of the earth

Answer 2

1/3

Question 3

Sea ice comprises ___ of the cryosphere

Answer 3

2/3

Question 4

Glaciers comprise ___ of the cryosphere

Answer 4

10%

Question 5

The frozen ground comprises ___of the cryosphere

Answer 5

20%

Question 6

How does snow reduce surface temperatures

Answer 6

Snow is a highly reflective surface (high albedo) so that sunlight bounces back into space, reducing surface temperatures.

Question 7

When the formation of snowfall _____ seasonal melting, this contributes to the formation of glaciers and ice caps.

Answer 7

exceeds

Question 8

Snowline

Answer 8

marks a boundary of an area that has snow year-round.

Question 9

Snowline location is controlled by:

Answer 9

variations in the thickness of winter snowpack and local topography, which its altitude typically changing from year to year depending on winter snow accumulation and summer melting.

Question 10

Primary ways in which snowline elevation varies

Answer 10

1. it is at a lower elevation in polar areas where temperatures are colder
2. it is lower in coastal areas where there is more moisture and therefore snow

Question 11

The process to form firn

Answer 11

1. existing snow is compacted by newer snow
2. evaporation occurs at the points of snowflakes
3. moisture freezes between the points

Question 12

Firn

Answer 12

a granular snow

Question 13

Firn gradually loses interstitial air to become ___.

Answer 13

ice

Question 14

As depth and time increase, the grains of ice become _______.

Answer 14

larger (due to recrystallization)

Question 15

Glaciers

Answer 15

Above a snowline, snow accumulates to form ice. Ice masses that flow under the influence of gravity are called glaciers.

Question 16

Glacial flow is fastest at the ____ of the glacial channel.

Answer 16

center

Question 17

Glacial flow is slowest at the ____ of the glacial channel due to ____.

Answer 17

edges of the channel due to friction with the bed

Question 18

In warm glaciers, movement occurs in:

Answer 18

due to internal flow and sliding at the base

Question 19

Cold glaciers do not slide because:

Answer 19

cold glaciers are frozen into the underlying bedrock and cannot slide

Question 20

Glaciers flow as ice crystals deform under stress. The deformation of ice crystals causes the ____ of ice crystal structures.

Answer 20

alignment

Question 21

Warm (temperate) glaciers

Answer 21

Have meltwater at their base, which allows for a flow along the bedrock. This causes warm glaciers to have a rounded terminus (or toe).

Question 22

Cold glaciers

Answer 22

Do not flow at their base. This causes cold glaciers to have a cliff terminus, including a cliff shape and avalanches at the bottom as the top moves the fastest.

Question 23

Region of accumulation

Answer 23

A region in a glacier where mass is net added

Question 24

Region of ablation

Answer 24

A region in a glacier where mass is net lost.

Question 25

Ablation is caused by:

Answer 25

melting, evaporation, or calving (breaking off part of the ice from the glacier)

Question 26

Calving

Answer 26

breaking off part of the ice from the glacier

Question 27

Accumulation and ablation areas of a glacier are separated by an _____.

Answer 27

equilibrium line

Question 28

Receding glacier

Answer 28

A glacier with a negative mass balance

Question 29

Glacier mass balance

Answer 29

accumulation minus it’s ablation

Question 30

How glaciers erode bedrock at their base:

Answer 30

Freeze-thaw cycles, and physical abrasion and plucking of rock fragments from the bedrock

Question 31

Chatter marks

Answer 31

crescent-shaped gouges that can form as rock fragments are dragged across a bedrock by a glacier

Question 32

Striations

Answer 32

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

Question 33

U-shaped Valleys

Answer 33

Valleys with steep sides and broad, flat bottoms are a typical erosional landform left by glaciers.

Question 34

Hanging valleys

Answer 34

often present at higher elevations and feed into U-shaped valleys

Question 35

Three types of erosional features

Answer 35

Cirques, Aretes, and Horns

Question 36

Cirques

Answer 36

bowl-shaped valleys formed at a glaciers head (by one glacier)

Question 37

Aretes

Answer 37

sharp-edged ridges formed by two glaciers

Question 38

Horns

Answer 38

pointed pyramids (formed by 3 glaciers)