Cold Environments Book 1

Question 1

What is the difference between total accumulation total ablation for the whole of the glacial year called?

Answer 1

The glacial budget

Question 2

Describe a polar glacier

Answer 2

The temperature of the ice remains well below freezing so it remains frozen to the bedrock so there is very little ice movement or erosion

Question 3

How does gravity influence the flow of ice?

Answer 3

The downhill force of the ice encourages it to move. The steeper the gradient the greater the pull of gravity

Question 4

In the summer what lubricates glaciers in Alpine areas?

Answer 4

Melt water helping them move down Valleys

Question 5

How does the temperature of ice influence its flow?

Answer 5

If the ice is too cold it will simply freeze to the bedrock like in Greenland and Antarctica in more temperature environments such as Alaska temperatures are higher so there is more melt water

Question 6

How does the mass of ice influence its flow?

Answer 6

The heavier the ice the more potential energy it has but it must overcome more friction ice masses don’t generally move until the thickness exceeds 60 m the greatest velocity of movement is at the firn line

Question 7

What is the term for when ice changes directly from a solid to a vapour?

Answer 7

Sublimation

Question 8

Is the Southern Ocean rich in animal life?

Answer 8

Yes despite being very cold

Question 9

What do glacial or polar areas tend to be covered by?

Answer 9

Ice sheets and glaciers

Question 10

What is the dividing line between the zone of accumulation and zone of ablation called?

Answer 10

The firn or equilibrium line

Question 11

Describe the compressional flow

Answer 11

It occurs below the third line and it is slower and causes ice to bunch up in areas with less steep gradients. Any crevasses created by extension of flow will be closed

Question 12

Describe basal flow/slippage

Answer 12

The movement of large blocks of ice usually in a series of short jerks. As the glacier moves there is friction, this is overcome by meltwater. The friction and pressure causes melting in the mouth water acts as a lubricant

Question 13

How cold can winters be in Alpine areas and why?

Answer 13

Temperatures can drop to -10° or less due to high altitude

Question 14

Where are tundra or periglacial areas found?

Answer 14

Dry high latitude areas such as northern Alaska and Canada, on the edge of polar environments

Question 15

Why can a glacier be described as a system?

Answer 15

They have input and outputs

Question 16

Where are the worlds largest glaciers found?

Answer 16

Polar regions

Question 17

If ablation is greater than accumulation what happens?

Answer 17

Glacial retreat

Question 18

Are cold environments only land based?

Answer 18

No they also include Maritime environment such as the Arctic and southern oceans

Question 19

Where are the worlds most actively moving glaciers found?

Answer 19

Alpine areas

Question 20

How does friction influence the flow of ice?

Answer 20

If the ice moves as one body the friction it exerts on the ground must be overcome

Question 21

Describe regelation slip

Answer 21

When the glacier meets a small obstacle pressure builds up on the up stream side allowing it to melt and slip over the obstacle on the down glacial side due to a lower pressure the meltwater refreezes

Question 22

What do Cold environments have a lot of and a little of?

Answer 22

They have a lot of snow and ice and little vegetation, they are sparsely populated

Question 23

What are the two types of basal flow?

Answer 23

Regelation slip and creep

Question 24

How does melt water influence ice flow?

Answer 24

It lubricates the ice allowing it to slip down hill

Question 25

What type of glacier is internal flow the main movement of?

Answer 25

Polar or cold based glaciers

Question 26

Define a cold environment

Answer 26

They are icy landscapes found at high latitudes (polar) and high altitudes (alpine)

Question 27

Describe extensional flow

Answer 27

It occurs above the firn line and causes the ice to Exceller rate and become thinner often resulting in crevasses as the ice thins there is less erosion

Question 28

How does geology influence the flow of ice?

Answer 28

Movement is faster over in impermeable surface as basal meltwater cannot sink into the bedrock

Question 29

How cold can areas in the Arctic Circle and Antarctic Circle reach?

Answer 29

Temperatures can often drop to -50°C

Question 30

Describe the winters of Alpine areas

Answer 30

Very cold with heavy snowfall

Question 31

Describe a temperate glacier

Answer 31

This includes most glaciers outside of Antarctica and northern Greenlund water is present throughout the ice mass and acts as a lubricant, meaning it can move between 20 and 200 m a year. It can erode, transport and deposit material

Question 32

What is the area near the source of the glacier called?

Answer 32

The zone of accumulation

Question 33

Describe the ice in the upper and lower layers of a glacier

Answer 33

In the upper layers the ice is more rigid, in the lower layers it can be described as plastic

Question 34

What is the area near the snout of the glacier called?

Answer 34

The zone of ablation

Question 35

Describe rotational flow

Answer 35

It occurs between extensional and compressional flow and can be birthplace of a Corrie

Question 36

What is the PMP at the surface of a glacier?

Answer 36

0° but this drops in the glacier as the ice is under pressure

Question 37

What are the two types of ice flow?

Answer 37

Compressional and extensional

Question 38

What does periglacial mean?

Answer 38

"Edge" of glacial

Question 39

What are the two main outputs of the glacier?

Answer 39

Melting and evaporation

Question 40

What are the two main components of ice movement?

Answer 40

Internal flow and basal flow

Question 41

Give examples of polar environments that are land based and marine based

Answer 41

Land based polar environment include Antarctica and Greenland Sea based polar environment include the Arctic and the Southern Ocean

Question 42

If accumulation is greater than ablation what process happens?

Answer 42

Glacial advance

Question 43

What causes glaciers to have a higher erosive power?

Answer 43

Higher inputs relative to outputs

Question 44

What is a glacial surge?

Answer 44

Where there is huge downhill movement of a glacier, an example would be the variegated glacier in Alaska. Which in the 1980s movie at speeds of up to 65 m a day

Question 45

Describe creep

Answer 45

This makes the glacier flow more plastically when it meets the larger obstacle it flows around it

Question 46

Describe the typical budget then an alpine or temperate glacier

Answer 46

It has a positive winter balance and a negative summer balance

Question 47

What is it called when ice bergs break off the glacier?

Answer 47

Calving

Question 48

Where are Alpine areas found and what may they contain, give some examples

Answer 48

They are found in high altitude areas and may contain small ice caps, mountain glaciers and tundra environments, examples include the Himalayas and the Alps

Question 49

Periglacial areas experience permanently frozen ground, what is the technical term for this?

Answer 49

Permafrost

Question 50

Do polar environments have high levels of precipitation?

Answer 50

No, they are very dry the Antarctic is actually classed as a desert

Question 51

Where is the fastest movement on a glacier?

Answer 51

In the centre at the top because there is least friction there. On the sides and bass there is more friction meaning there is slower movement

Question 52

When accumulation and melting are equal what state is the glacier said to be in?

Answer 52

Steady state

Question 53

What happens in the summer in periglacial areas?

Answer 53

The surface layer thaws enabling hardy plants to grow

Question 54

Describe the summers in Alpine areas

Answer 54

Relatively warm with temperatures exceeding 20° sometimes

Question 55

Describe internal flow (internal deformation)

Answer 55

The movement within in glacial ice due to gravity ice crystals orientate themselves in the direction of glacial movement meaning that they can slide past each other. Crevasses develop as the ice moves faster

Question 56

What is the main input to glaciers and what happens to it over the years?

Answer 56

It is snow, it gradually turns from low-density white ice crystals to high-density clear glacial ice

Question 57

What is the pressure melting point of ice?

Answer 57

Point at which ice is on the verge of melting

Question 58

Are periglacial areas permanently covered by ice?

Answer 58

No

Question 59

In Alpine areas what feed glaciers?

Answer 59

Heavy snowfall

Question 60

What are the two types of glaciers?

Answer 60

Temperate/warm based or polar/cold based

Question 61

Name the six factors that influence the flow of ice

Answer 61

1. Gravity 2. Friction 3. The mass of ice 4. Meltwater 5. Temp of ice 6. Geology