Glaciation

Question 1

Niche glaciers

Answer 1

• Very small
• Occupy hollows
• North-facing slopes

Question 2

Piedmont glacier

Answer 2

• Valley glacier extent
• On lowland areas
• Spread out and merge

Question 3

Snowline

Answer 3

• The point above which snow and ice cover the ground throughout the year
• Snow and ice has survived summer melting

Question 4

Aspect

Answer 4

The direction in which a slope faces

Question 5

Negative balance

Answer 5

Ablation exceeds accumulation = more mass is lost than gained

Question 6

Positive balance

Answer 6

Accumulation exceeds ablation = more mass is gained than lost

Question 7

Feedback

Answer 7

Balance in a system between inputs and outputs, then the system is said to be in a state of dynamic equilibrium

Question 8

Positive feedback

Answer 8

Where the effects of an action are multiplied by subsequent knock-on or secondary effects

Question 9

Negative feedback

Answer 9

Where the effects of an action are nullified by its subsequent knock-on effects

Question 10

Glacial budget

Answer 10

Net balance between accumulation and ablation within a glaciers system

Question 11

Glacier

Answer 11

Mass of ice that flows down hill due to gravity

Question 12

Valley glacier

Answer 12

• Fill valleys

- Several KM long

Question 13

Corrie glacier

Answer 13

• Small glacier
• Bowl shaped hollows
• High up in mountains

Question 14

Ice sheets

Answer 14

Domes of ice covering huge areas of land

Question 15

Five types of glacier

Answer 15

1. Valley
2. Corrie
3. Niche
4. Piedmont
5. Ice sheets

Question 16

What can glaciers be classified as?

Answer 16

• Morphology

- Thermal Regime

Question 17

Thermal Regime

Answer 17

How they move

• Temperate glaciers
• Polar glaciers

Question 18

Temperate glaciers

Answer 18

• Occurs in areas with milder summers = melting
• Meltwater acts as a lubricant = steep relief
• Move by basal flow, extending/compressing flow, creep and surges
• More likely to erode, transport and deposit material

Question 19

Polar glaciers

Answer 19

• Occur in very cold areas = below 0 degrees so no meltwater occurs
• Frozen to beds = move by internal flow
• Less erosion, transportation and deposition

Question 20

Relationship between snowline, latitude and altitude

Answer 20

Higher the latitude, lower the snowline in elevation

Question 21

Glacier inputs

Answer 21

• Snow
• Ice
• Water vapour
• Rock debris
• Geothermal heat
• Gravity

Question 22

Glacier outputs

Answer 22

• Water vapour
• Meltwater
• Glacial debris
• Iceburgs

Question 23

Glacier stores

Answer 23

• The glacier

Question 24

Glacier transfers

Answer 24

• Ice flow

Question 25

Accumulation

Answer 25

Inputs = mass is gained

Question 26

Ablation

Answer 26

Outputs = mass is lost

Question 27

How snow becomes ice

Answer 27

1. Snow initally falls as flakes which trap air 2. Snow accumulates, lower layers are slowly compressed by the upper layers, turns into FIRN 3. Melt-water seeps into gaps between snow particles + freezes, further compacting mass 4. Further accumulation squeezes out air from lower layer, after time solid ice develops 5. Ice forms which changes colour, blue = no ice present 6. If mass of ice becomes large enough = glacier

Question 28

Mer de Glace, France

Answer 28

- Retreating glacier - Longest glacier in the French Alps - Temperate glacier

Question 29

Hubbard Glacier, Alaska

Answer 29

- Advancing glacier - 38 miles long - Temperate glacier

Question 30

Historical patterns of ice advance and retreat

Answer 30

- Little ice age , 1644 = annual temp across the northern hemisphere declined by 0.6c - Medival warming period followed = period of warming began in the late 19th century

Question 31

Calving

Answer 31

- Breaking off of ice from the snout

Question 32

Sublimation

Answer 32

- The process of snow/ice changing into water vapour

Question 33

Desublimation

Answer 33

- The process where water vapour changes directly into ice.

Question 34

Example of positive feedback

Answer 34

- Arctic ice melts - Land and water exposed - Darker and duller surfaces = Lower albedo - More solar radiation absorbed = Surface warms = More arctic ice melts