Glaciation exam

Question 1

Name 5 erosional processes!

Answer 1

Abrasion
Plucking 
Fracture and traction 
Dilation
Meltwater erosion

Question 2

Explain how abrasion works.

Answer 2

Individual stones lead to micro features such as striations and chatter marks. The rocks polish the underlying rocks by “sand paper” action.

Question 3

Explain how plucking works.

What type of process is it?

Answer 3

A two stage process with the initial widening of the joints by fracture and the subsequent entrainment of any loosened material.

Question 4

Explain how fracture and traction work.

What does variations in pressures lead to?

Answer 4

Occur as a result of the crushing effect of the weight of moving ice passing over the rock and variations in pressures lead to freezing and thawing of the meltwater, which aids the plucking process.

Question 5

Explain how dilation works.

Answer 5

Occurs as overlying material is moved, causing fractures in the rock parallel to erosion surfaces as the bedrock adjusts to the unloading.

Question 6

1. Explain how meltwater erosion works.

2. What 4 processes does glacial meltwater play an important role in?

Answer 6

1. Can be both mechanical and chemical, whereby glacial meltwater can dissolve minerals and carry away the solutes, especially in limestone rocks.
2. •erosion •disposition •transportation •entrainment (rock in ice) through freeze thaw of meltwater

Question 7

1. What are sub aerial processes?

2. Name the three types of weathering!

Answer 7

1. Mixture of weathering and mass movement

2. Physical, chemical and biological.

Question 8

What is physical weathering? Provide an example!

Answer 8

The facture and breakdown of rocks into fragments. An example is freeze thaw which is when water creeps into the rock cracks and freezes and melts over and over again, causing the cracks to expand.

Question 9

What is chemical weathering? Provide an example!

Answer 9

Involves decomposition of rocks (literally, changing the minerals). Chemical weathering occurs as a result of a weak chemical reaction between water and rock. eg. with limestone.
Example is acid rain.

Question 10

What is biological weathering? Provide an example!

Answer 10

Growing plant roots widen cracks as does the leverage created by bushes and trees swaying in strong winds. Burrowing animals and nesting birds excavate material in partially weathered and eroded cliffs.

Question 11

What is mass movement?

What are the two processes with examples?

Answer 11

The movement of material downslope because of gravity. This can be a slow process in the case of soil creep or fast in the case of rockfalls. Water commonly acts as a lubricant in mass movement.

Question 12

What are 7 examples of mass movement?

Answer 12

Soil creep, earth flows, land slide, mud flows, slumps, rockfall and run-off.

Question 13

What are the 5 economic values of glaciated landscapes?

Answer 13

Farming, forestry, mining and quarrying, hydroelectricity and tourism.

Question 14

Describe the economic value of farming.

What are the cons of farming in developing regions? (4)
what has caused the pros?

What are the cons of farming in developed regions?

Answer 14

In mountainous areas in developing regions, there may be limited transport links and access to essential supplies and markets may be poor; employment opportunities are also limited. Development on the internet and mobile phones has revolutionised their lives, providing many opportunities for cottage industries. In developed countries, the agriculture in upland glaciated areas is primarily pastoral because the above average precipitation and shallow soils, which together make cultivation difficult.

Question 15

Describe the economic value of forestry.

What are the disadvantages of hill farming?
What is hill farming dependent on?

Answer 15

Hill farming is an increasing struggle in may regions and uplands are increasingly used for forestry. This is depending on the farm prices and the degree of government support systems.
Also fast growing trees such as conifers, which tolerate harsh climates and acidic soils would not be suitable for other land uses.

Question 16

Describe the economic value of hydroelectricity.

What are the pros of HEP? (3)
What are the sources of HEP? (3)
What are the cons of HEP? (2)

Answer 16

In developing countries, micro-hydros can revolutionise the quality of life. Hydroelectric power is a major use of water delivered from glaciers. New Zealand and Norway get 90% of electricity from hydroelectricity. Natural ribbon lakes or a dam and reservoir in a glaciated valley provide the HEP. Which makes it a renewable green source.
Issues with reliability of water supply and environmental concerns over damming of rivers.

Question 17

Describe the economic value of mining and quarrying.

What are the pros?
What plays an important role?
What can you find in active areas?

Answer 17

Pre sorted by meltwater into sands and gravels tonne sold as aggregates making them useful for making concrete.
Glacial erosion is a key factor in removing regolith and vegetation to expose economically valuable rocks.
In active areas there are mines and quarries of mineral deposits and ores, as well as slates as many glaciated mountains are made from igneous and metamorphic rock.

Question 18

Describe the economic value of tourism.

Why do tourists visit glaciated landscapes?
What is the disadvantage for the landscapes?
What has brought mass tourism and what has this caused?

Answer 18

Tourists visit glaciated landscapes to view the spectacular scenery or participate in outdoor activities. They are increasingly visited for the glaciers themselves, putting pressure on some very fragile landscapes.
Long haul travel and modern communications had brought mass tourism, making places more popular and benefiting the economically.

Question 19

How does climate change increase the rates of ablation?

Answer 19

By increasing temperature and precipitation type and amount.

Question 20

How are cold based glaciers affected by climate change?

Answer 20

It increases the rate of melting and calving which increases the loss of mass through the creation of icebergs.

Question 21

How does climate change affect ablation on a meso scale?

Answer 21

Increases altitude of the equilibrium line of a glacier mass balance system.

Question 22

How does climate change affect warm based glaciers?

Answer 22

Increases temperature which decreases the rate of accumulation as there is less snowfall and store of ice.

Question 23

1. How does the Milkankovitch cycle relate to climate change?

Eccentricity wobble

Answer 23

When the earth is at its tilt (closest to the sun) it will decrease the distance the sun rays have to travel so the glacier will be exposed to more solar radiation, increasing ablation and melting ice/snow.

Question 24

CASE STUDIES- legislative framework to protect glaciated landscapes

1. Name an international legislative framework for glacial landscapes
2. What is the Antarctic Treaty?
3. Has the treaty been successful?
4. What is the management of the Arctic? (National scale)

Answer 24

1. Antarctic Treaty System (ATS)
2. Made in 1959 for all areas south of 60^S. Established the Antarctica as a continent of peace and science and set all existing territorial claims of 7 counties to one side. 60 counties have signed representing 88% of worlds people. 4 international agreements have been adopted to form the ATS including the 1982 Conservation of Antarctic Marine Living Resources. There is also special protection of flora and fauna to prevent marine pollution and waste disposal.
3. One of most successful international agreements. However, the other large polar area (Arctic) is far less healthy. This area is surrounded by superpowers (Russia and USA) compared to Antarctica being 97% covered by ice.
4. Arctic Council (8 countries have territory in Arctic waters) - led to geopolitical tensions with the melting of sea ice creating greater accessibility via opening of new sea routes and feasible exploitation of mineral deposits.

Question 25

Periglaciation PLACE STUDY 
1. Where are periglacial landscapes distributed? 
2. What are periglacial landscapes? 
3. What are these landscapes called? 
4. Why is a tundra created? 
5. Name 3 periglacial landforms 
A) how is patterned ground formed? 
B) how are pingos formed? 
6. Name 3 periglacial processes 
7. What is permafrost? 
8. Explain the 2 types of permafrost

Answer 25

1. High latitude areas - Alaska, Northern Canada, Northern Russia
2. Non-glacial cold environments - extreme cold, dry conditions and permafrost
3. Tundra - treeless vegetation with high grass
4. Tree 🌲 growth is hindered by mean annual temperatures of less than 3^c and minimum temperatures as low as -50^c.
5. Pingos, patterned ground and ice wedges
   A) by a series of movements resulting from frost action. Frost pushes stones upwards forming circles
   B) growth of ice core forces up sediments and melts at the surface, causing top of pingo to collapse forming a crater filled with meltwater
6. Freeze thaw, nivation and meltwater erosion
7. Permanently frozen ground with soil temperatures below 0^c for at least 2 years.
8. •Continuous permafrost - found in high latitudes where all ground is permanently frozen and very little surface melting occurs.
   •discontinuous permafrost - shallower and contains some unfrozen ground. Surface layer of ground melts in summer months.

Question 26

1. What is the glacier mass balance system?
2. Name the 2 inputs
3. Name the 2 outputs
4. Explain how the system works

Answer 26

1. The gains and losses of the ice store in the glacier system
2. Energy and accumulation
3. Ablation and calving
4. When accumulation exceeds ablation in the winter period the glacier increases in mass and snout advances. In the summer when ablation is more than accumulation, the glacier has a negative regime causing the glacier snout to retreat.

Question 27

1. Name the 3 processes that cause glacier movement
2. How does basal sliding move ice?
3. How does internal deformation move ice?
4. How does subglacial bed deformation move ice?

Answer 27

1. Basal sliding, internal deformation and subglacial bed deformation
2. Meltwater beneath warm based glaciers reduces friction with the entrained debris and underlying bedrock.
3. Cold based glaciers are unable to move by basal sliding because temperature is below the pressure melting point.
4. 90% of forward glacier movement, where glacier moves over weak rock, moving the ice on top of it along with it.

Question 28

1. . What is supraglaical entrainment?

2. What is subglacial entrainment?

Answer 28

1. Material falls from hills being washed onto the glacier

2. Material eroded from glacier bed and frozen to the base from subglacial streams.

Question 29

1. Name the 4 threats to glaciated landscapes
2. What are avalanches? (Example)
3. What are lahars? (Example)
4. What are glacial outburst floods?
5. Where are glacial outburst floods common and why?

Answer 29

1. Avalanches, lahars, glacial outburst floods and polar tourism
2. Snow pack failures which kill 200 people per year mostly in the Alps
3. Volcanic activity cause glacier melting. For example, 1985 Nevado Del Ruiz which rushed down town of Armero with mud flow 8m deep. Killing 23,000 people instantly.
4. Icelandic term is jokulhlaup - powerful flood caused by sudden discharge of a subglacial or ice moraine dammed lake.
5. Iceland 🇮🇸 because of volcanic activity generating sudden releases of meltwater. In 1996 an eruption burst through the glacier causing $15 million infrastructure damage.

Question 30

Causes of long term climate change is the Milankovitch cycle

1. What are interglacials?
2. What are 2 causes of short term climate change?
3. What is the big problem with solar forcing?

Answer 30

1. Warmer periods - like today
2. Solar forcing and volcanic causes
3. Solar radiation caused by sunspot activity is only 0.1% so is not enough to explain climate fluctuations. However, scientists suggest 20% of 21st century climate warming was related to solar forcing.