Ice On The Land

Question 1

What do glaciers do?

Answer 1

Erode, transport and deposit material.

Question 2

What is a glacier?

Answer 2

A glacier is a long standing mass of ice that moves very slowly downhill.

Question 3

What is the name given to the formation of glaciers?

Answer 3

Glaciation

Question 4

What is the difference between a seasonal period and glacial period?

Answer 4

Seasonal periods last few months where as and interglacial period can last around several hundreds of thousands of years. We are in an interglacial period at the moment.

Question 5

Explain how glaciers form

Answer 5

A glacier is a system with inputs (accumulation) and outputs (ablation).
The snow falls and becomes compacting, releasing air, turning firn into ice crystals.
The ice crystals become denser and become clearer glacial ice
Avalanches can also be a source of accumulation when they release snow
Ablation happens mostly at the snout of the glacier where the ice melts because it’s warmer
Calving is when ice breaks off at the snout
Another output is by evaporation or sublimation

Question 6

Average movement of a glacier?

Answer 6

1-30m a day

Question 7

Name some factors that affect the movement of a glacier.

Answer 7

Slope, snowfall and meltwater at the base of the glacier.

Question 8

What is the internal deformation of ice?

Answer 8

When the weight of the ice deforms the crystals. This usually happens near the glacier bed where pressure is the highest.

Question 9

What is a positive and negative budget?

Answer 9

If accumulation is larger than ablation this is a positive budget. This means the glacier will advance. This usually happens in winter or glacial periods. If ablation is greater than a accumulation, this is a negative budget and the glacier will retreat. This usually happens in summer or interglacial periods.

Question 10

What is the glacial budget?

Answer 10

It is the balance between accumulation and ablation in a glacier. Its determines whether the glacier will advance or retreat.

Question 11

Explain how glaciers move

Answer 11

The ice mass flows from the zone of accumulation and moves downslope like a fluid due to gravity and the internal deformation of ice. Meltwater at the base of a glacier acts as a lubricant for the ice to slide. This is basal sliding.

Question 12

What is it short term glacial budget change?

Answer 12

Seasonal change

Question 13

What is a long term glacial budget change?

Answer 13

Climate change (Ice ages, glacial and interglacial periods, etc.)

Question 14

Thought human causes of climate change.

Answer 14

The industrial revolution and the introduction of machines and the burning of fossil fuels such as: oil contribute to the overall warming of the earth. The burning of coal releases greenhouse gases which acts as a blanket century trapping heat and stopping it returning to space.

Question 15

Give some examples of natural causes of global temperature change.

Answer 15

The albedo effect means the whiteness of the surface of the earth. The white surface is (i.e. the more ice)The more sheet is reflected. The more the ice melts, the dark seawater will absorb heat instead causing the temperature to rise. Volcanic winter caused by Yellowstone volcano means ash will blackout the sun and cause global cooling.

Question 16

Explain the process of freeze thaw weathering.

Answer 16

Water enters the joint or crack in a rock . Weather reaches below 0°C during night or winter. Water expands when frozen as it does this continuously in the crack, since the freezing and melting of the water is a repeated process, the rock breaks up.

Question 17

Examples of human global temperature change causes.

Answer 17

Greenhouse gasses being emitted means energy is trapped. Carbon dioxide acts as a blanket for heat, preventing it from returning to space therefore heating up the air temperature.

Question 18

What is weathering?

Answer 18

Weathering is the breakdown of rocks in situ

Question 19

What are the three types of weathering?

Answer 19

Physical, chemical and biological

Question 20

What is erosion?

Answer 20

Erosion is the wearing away of rock and its removal by streams, ice, waves and wind. Erosion, transportation deposition help shape the land.

Question 21

Explain how an arête forms

Answer 21

An arête is a two-sided ridge on top of a mountain
It forms when erosion in two back to back corries causes the land in between to become even narrower, forming a sharp ridge

Question 22

Explain how a corrie forms

Answer 22

A Corrie is an armchair shaped hollow with a steepened back wall.
Snow accumulates in a hollow and compacts into ice over thousands of years.
The glacial ice starts to flow downhill in a rotational slip, causing abrasion and the steepening of the back wall as the process of plucking rips the rock off.
Freeze-thaw weathering on the back wall adds more rock material to the glacier causing further abrasion at the base of the hollow, deepening it.
Where the gradient is less, erosion occurs less, forming a rock lip near the end of the glacier
When the glacial period has passed, and the corrie is left,a tarn can form in the hollow, which is a small lake.

Question 23

Explain how a pyramidal peak forms

Answer 23

A pyramidal peak is a three sided slab of rock on the top of a mountain.
It forms when three or more corries erode backwards and meet
The glacier erodes the rock, causing steep, angular sides and a sharp, pointed summit
e.g. the Matterhorn

Question 24

What is a ribbon lake?

Answer 24

Glacial erosion is uneven. Some rock is eroded more that others due to the strata. Soft rock erodes more and there is more moraine, the opposite occurs for hard rock. Water will fill the eroded flat rock in interglacial periods.

Question 25

Explain the formation a glacial trough (U-shaped valley)

Answer 25

A glacial trough is a wide, steep-sided, flat-bottomed valley that has been eroded by a glacier They are formed by a valley glacier that flows down a V shaped valley As the glacier moves down the valley, it plucks and abrades the base and sides of the valley The subglacial moraine in the glacier widens and deepens the valley floor Truncated spurs also form (*if 6 mark Q, explain formation of truncated spurs too)

Question 26

Explain the formation of a ribbon lake

Answer 26

A ribbon lake is a long and narrow lake in the floor of a U-shaped valley It is formed when a glacier moves over soft and hard rock The hard rock does not erode as quickly but where there is soft rock, the glacier will easily erode the floor making it deeper than the shallow walls, forming a rock basin. When the glacier retreats, the melted water collects in the bottom of the U-shaped valley, forming a long narrow lake.

Question 27

What is the competence of a glacier?

Answer 27

It's ability to carry material.

Question 28

What is a misfit stream?

Answer 28

A misfit stream is a small, narrow river which flows through the glacial valley floor. Its small size is out of proportion with the large scale of the valley They are formed in an inter-glacial period and did not erode the valley

Question 29

What is scree?

Answer 29

Material that has been deposited, weathered or eroded. Deposits of angular rock fragments found at the foot of rocky features. Scree itself is not a landform.

Question 30

Human uses of ribbon lakes?

Answer 30

Skiing, sailing and fishing.

Question 31

Explain the formation of truncated spurs

Answer 31

Truncated spurs are higher areas on the straight rocky sides of the glaciated, U-shaped valley At the snout of the glacier, bulldozing occurs and the former interlocking spurs of the V-shaped valley are bulldozed through This is aided with the processes of abrasion and plucking, forming truncated spurs at the sides of the valley

Question 32

Chamonix winter attractions

Answer 32

``` Skiing, snowboarding Mountain climbing Ice skating Sledging Spas Access to slopes via cog railways or cable cars Museums 60,000 tourists ```

Question 33

Chamonix summer attractions

Answer 33

``` 40km of mountain bike roads 350km of hiking trails Canoeing, rafting Helicopter flights Bird watching Mer de Glace - it is the largest glacier in France (7km long, 200m at its deepest point and you can go inside it with access via the Montenvers railway 100,000 tourists ```

Question 34

Positive social impacts of Chamonix tourism

Answer 34

Improvement in transport and health care Job availability Locals supplied with good facilities and activities Clean, safe pedestrianised streets

Question 35

Positive economic impacts of Chamonix tourism

Answer 35

Local employment - 2500 people work as seasonal workers every year in the tourism industry Helps local businesses - Compagnie du Mont Blanc is a company that runs ski lifts and rail transport Good for local economy

Question 36

Positive environmental impacts of Chamonix tourism

Answer 36

The environment is well cared for Local animals are protected by organisations There are schemes to keep slopes and woodland areas nice

Question 37

Negative social impacts of Chamonix tourism

Answer 37

Narrow roads get congested Towns get crowded and noisy Conflict between tourists and locals/tourists Big, loud events at night Big tourism activities causing noise Tourist developments e.g. ski slopes have an increased risk of avalanches - more deaths from avalanches e.g. in 1999 an avalanche killed 12 people

Question 38

What is an avalanche?

Answer 38

A rapid downhill movement of a mass of snow, ice and rocks, usually in a mountainous environment. They move at speeds of up to 300km/h.

Question 39

Negative economic impacts of Chamonix tourism

Answer 39

Local services and shops expensive for locals Jobs are temporary Expensive property Property can be damaged by tourists Animal gates left open, affects farmers livelihoods

Question 40

Negative environmental impacts of Chamonix tourism

Answer 40

Large number of tourists cause a lot of traffic which increases pollution - a study from 2002 to 2004 showed that traffic pollution was worse in the Chamonix region than in the centre of Paris Mountain footpath erosion Farm animal gates left open - harm to animals Litter can end up in the glacier - glass bottles are a safety hazard A huge amount of energy is used to run the facilities for tourists e.g. the hotels, ski lifts and snow-making machines - increases CO2 emissions, which increases global warming

Question 41

Causes of avalanches

Answer 41

Heavy snowfall - adds weight to snow, creating layers, making slab avalanches more likely Tree removal - trees help to stop avalanches Heavy rainfall - lubricates slope Temperature rise - sudden rise in temperature can cause melting (lubricates slope) and this can lead to avalanches in spring Human factors - off piste skiing, people ski in areas of fresh snow that haven't been assessed for avalanche risk Steep slopes - avalanches are most likely at 30-45°

Question 42

How are avalanches managed?

Answer 42

Walls and fences - impede avalanches Afforestation - trees impede avalanches Gully - controls and makes a path for the avalanche towards the avalanche shed Avalanche shed - collects snow from avalanche Wedge - curves snow around pylons Large, flat urban-free areas - space for snow to deposit

Question 43

Negative social effects of avalanches

Answer 43

People die Power lines can be brought down, no electricity Mountains close People can face criminal charges

Question 44

Negative environmental effects of avalanches

Answer 44

Trees uprooted | Biodiversity disrupted

Question 45

Negative economic effects of avalanches

Answer 45

Ski resorts lose customers and tourism Rebuilding Flights cancelled

Question 46

Immediate avalanche responses

Answer 46

Helicopters locate survivors

Question 47

What is sustainable management?

Answer 47

Management approaches that conserve the environment for future generations.

Question 48

What are fragile environments?

Answer 48

Environments that are easily unbalanced and damaged by natural or human factors. Alpine environments are fragile environments and need careful, sustainable management

Question 49

Long term avalanche responses

Answer 49

``` Rules are stricter Skiers made to wear Avalanche transceiver Instructors warn skiers Rescue is free More equipment ```

Question 50

How are drumlins formed?

Answer 50

The competence of the glacier is low Because it is filled with sediment which encourages deposition of sediment. Melting glaciers meets small obstacles and deposits Boulder clay creating the stoss end because Ice deposits more sediment when facing up valley. The glacier continues to move and the Boulder clay Moulded into shape around the obstacle, creating the lee end.

Question 51

What are adaption strategies in fragile environments?

Answer 51

Maintain ski tourism - artificial snow, develop on higher terrain, change slope design Subsidies - annual or single government contributions. Alternatives to ski tourism - non-snow related winter activities, all year tourism Fatalism - carry on as usual or cancel ski tourism.

Question 52

How are drumlins formed?

Answer 52

A drumlin is an egg-shaped hill made from boulder clay (till). They usually occur together as a swarm When the competence of the glacier is low, this encourages deposition of sediments The melting glacier meets small obstacles which are enough to encourage deposition of boulder clay from the ice at the side of the obstacle, facing up-valley. This forms the stoss end As the glacier continues to move, the boulder clay at the bottom of the glacier is moulded into shape around the obstacle. This forms the lee end. Over time, the drumlin is re-shaped by further ice movements

Question 53

Label drumlin:

Answer 53

``` Made of till Usually found in swarms No core sediment Always longer than wide Creates basket of eggs scenery 0.5 km width Steep, stoss end Gentle, lee slope 400m-1km long ```

Question 54

What is abrasion?

Answer 54

A process of erosion in which rocks carried in the bottom of the ice wear away the surface rock over which the ice passes, leaving behind scratches and striations on the rock

Question 55

Why does Chamonix need management? (economic reasons)

Answer 55

40% less snow in the areas under 1000m above sea level over the last 50 years - higher pressure on high altitude ski slopes 15% of French ski areas are covered by snow canons to preserve summer skiing - in some areas, snow-making consumes more power than an entire ski lift system as the water to create artificial snow needs to be cooled down to 10 degrees + requires as much water as a town with 170,000 inhabitants Winter sports industry is worth £64 bn per year - a loss of income would have widespread economic impacts in the region Due to unreliable source of income, banks in Switzerland have refused to lend money to resorts below an altitude of 1500m Cost of maintenance of cable-car stations and ski lift masts due to increased risk of landslides

Question 56

Why does Chamonix need management? (environmental reasons)

Answer 56

Accumulation of fresh snow has halved in the past 40 years - Mer de Glace has lost 65m in depth and 300m in length in the last 20 years 15% of French ski areas are covered by snow canons to preserve summer skiing - noise and visual pollution + cooling agent Snomax is added which can pollute the local environment Cigarette litter - toxins contaminate water Hotels have an inefficient use of energy - large carbon footprint and surrounding hillside is eroded as more hotels are built High use of private vehicles, difficult to arrive by rail as no direct service from closest airport - source of 80% of carbon emissions in Chamonix The Alps is the source of three main rivers of Europe: the Rhine, the Rhone and the Po - Glacial retreat will lead to unreliable fresh water supply in the region (social) Global warming leads to melting of the permafrost, increasing the risk of landslides

Question 57

What are management strategies in Chamonix?

Answer 57

1) Espace Mont Blanc - encourages tourists not to litter, there are recycling points around the valley + they have a blog that reports environmental news, raising awareness of the green agenda, encouraging responsible tourism 2) Some hotels are now using low-energy lighting, limiting water use, providing recycling bins for guests, refurbishing using locally-sourced materials, geothermal energy for heating and installing solar panels - reducing their carbon footprint 3) Improving public transport reducing use of private vehicles - free shuttle service, all buses are fitted with particle filters to further reduce air pollution 4) Tomorrows Valley: initiative with the local community that plans for sustainable management to minimise environmental impact - preserves natural wetland and bogs, plants trees, maintains and way marks footpaths, cleans rivers, supports farming 5) Chamonix Municipality - provides clean energy buses to make the transport service in Chamonix more environmentally friendly

Question 58

What are the negative about the management strategies in Chamonix? ( useful for a 'discuss' question)

Answer 58

They are still lacking in a rail improvement strategy One strategy is to cover glaciers with synthetic carpet made of reflective material to reduce surface melting - relatively ineffective strategy as they can only protect the glaciers temporarily

Question 59

Location of the Athabasca glacier

Answer 59

State of Alberta in West Canada, in the Canadian rockies

Question 60

Some facts about the Athabasca glacier

Answer 60

6km long, 6km2 area, one of the most visited glaciers in the world because of its proximity to a major highway (Icefields Parkway)

Question 61

Causes of retreat of the Athabasca Glacier

Answer 61

The glacier has been melting since the middle of the 19th century, long before human-caused climate change becomes significant. After 1920 human influence rose steadily. Currently, the human contribution to glacier melt is about two-thirds. Throughout the 21st century the human contribution is suspected to increase even more.

Question 62

Evidence of retreat of the Athabasca Glacier over time

Answer 62

It has receded 1500m from the furthest recorded extent and currently has a negative glacial budget It has retreated about 200m since 2002 The glacier was over 100m less thick in 2002 than 1906 It is melting faster than it has been in the past 40 years It used to flow past Sunwapta Lake but is now further back The Parks Canada agency have placed markers on the walk up to the glacier, showing where the snout of the glacier reached in previous years - shows visitors just how quickly the glacier is retreating

Question 63

Evidence for climate change from the Athabasca Glacier

Answer 63

Only recently started retreating extremely quickly In accordance with the rise of greenhouse gas emissions Has retreated in time with the wolds rising temperatures * But has been retreating before human influences therefore not enough evidence for global warming

Question 64

Economic impacts of unreliable snowfall

Answer 64

Making artificial snow, 15% of French ski resorts are covered by snow canons - in some resorts, making snow consumes more power than running ski lifts If skiing is the main attraction, when there is too little snow it can be unsafe or not possible to ski. If there is too much snow, slopes are unstable increasing the possibility of an avalanche - both reduce tourists numbers

Question 65

Social impacts of unreliable snowfall

Answer 65

European resorts have experienced a decrease in precipitation over the past five years - some resorts have had to stringently control their water supply in order to conserve supplies The chemical additives used in snow-making affect the drinking water for resorts People losing jobs, have to move elsewhere§

Question 66

Environmental impacts of unreliable snowfall

Answer 66

40% less snow in the areas under 1000m above sea level over the last 50 years - led to greater pressure on high-altitude ski slopes, which are environmentally sensitive areas ( fragile alpine environments) The chemical additives used in snow-making affect the natural vegetation

Question 67

Economic impacts of glacial retreat

Answer 67

Lower ski resorts shutting down Once a glacier has completely retreated, the amount of meltwater decreases - the industries that rely on the supply of meltwater e.g. agriculture for irrigation and HEP for electricity production, will make less money and could shut down

Question 68

Social impacts of glacial retreat

Answer 68

The Alps is the source of three main rivers of Europe; the Rhine, the Rhone and the Po. Glacial retreat will lead to unreliable freshwater supply to the region Distributions to power supplies from HEP could leave some people with an unreliable power If businesses shut down, local people will have to move away to find work If an area's population declines, local services and recreational facilities will also shut down The ice will no longer be available for local people e.g. for trekking and ice climbing

Question 69

Environmental impacts of glacial retreat

Answer 69

Increase in natural hazards - rapid melting can cause flooding, rockslides and avalanches. These hazards destroy habitats and disrupt food chains Meltwater from retreating glaciers contributes to rising sea level which destroys coastal habitats by causing flooding and erosion Lots of fish species are adapted to live in cold meltwater that comes from glaciers - when the glaciers have completely melted, there's no cold meltwater so these fish species may die out Harmful pollutants can be trapped in glacial ice e.g. the pesticide DDT that was used from the 1940s to 1980s - rapid melting releases them into the environment, polluting streams and lakes

Question 70

What are the impacts of global warming on winter tourism in the alps?

Answer 70

Unemployment for local people Small businesses closing Even if ski resorts decide to move higher up the mountain, then the negative impacts on tourism may become bigger just in specific areas

Question 71

Where are rates of abrasion highest?

Answer 71

Where there is a large amount of debris in the glacier Where the ice is thick so there is more pressure Where the rock debris is more resistant than the bedrock

Question 72

What is plucking?

Answer 72

A process of erosion in which blocks of rock are torn away from the bedrock as the ice moves away

Question 73

Where are rates of plucking highest?

Answer 73

Where the bedrock is well-jointed Where there are large amounts o meltwater Where the ice is thick so there is more friction

Question 74

How does ice transport material?

Answer 74

Ice transports material supraglacially, subglacially or englacially. The material that it carries has been eroded by plucking, bulldozing and abrasion and weathered by freeze-thaw weathering

Question 75

What is lateral moraine?

Answer 75

Material carried and deposited on the sides of the glacier

Question 76

What is medial moraine?

Answer 76

Material carried and deposited in the centre of the glacier

Question 77

What is terminal moraine?

Answer 77

Material found at the very end of the glacier

Question 78

What is ground moraine?

Answer 78

A thin layer of material depositied over a large area as the glacier melts

Question 79

What is subglacial moraine?

Answer 79

Material carried along the base of the glacier

Question 80

What is bulldozing?

Answer 80

When the ice pushes loose material in front of it

Question 81

What is rotational slip?

Answer 81

Rotational slip is when ice is trapped in hollows or depressions high up on the valley sides are unable to move downhill. Gravity will therefore encourage it to move in a circular movement

Question 82

What is basal sliding?

Answer 82

When the huge pressure and weight of ice causes a temperature rise at the base of the glacier leading to melting, which produces a great deal of meltwater. This lubricates the underside of the glacier enabling it to slide downhill

Question 83

Why does deposition by glaciers occur?

Answer 83

When the ice carrying the material melts, the material is left behind on the valley floor It also occurs when the glacier has reached its carrying capacity

Question 84

How does glacial ice form?

Answer 84

Snowflakes --> granular snow --> firn --> glacial ice

Question 85

What is a corrie glacier?

Answer 85

A process called rotational slip causes the ice to retreat from the back wall, creating a crevasse (forming a corrie)

Question 86

What is a valley glacier?

Answer 86

Streams of flowing ice in steep-walled, U-shaped valleys

Question 87

What is an ice sheet?

Answer 87

A mass of glacier ice covering an area of land over 50,000km2

Question 88

What is an ice cap?

Answer 88

A mass of glacier ice covering an area of land less than 50,000km2

Question 89

What is an ice age, when was the last ice age called and when was it?

Answer 89

Ice ages are cold periods that last for millions of years when large masses of ice cover parts of the Earth's surface Pleistocene that began around 2.6m years ago

Question 90

What are glacial periods and how long do they last?

Answer 90

Cooler periods when the ice advances to cover more of the Earth's surface. Each one lasts about 100,000 years

Question 91

What are interglacial periods and how long do they last?

Answer 91

Warmer periods when the ice retreats to cover less of the Earth's surface. Each one lasts around 10,000 years

Question 92

When was the last glacial period?

Answer 92

It began around 100,000 years ago and ended around 10,000 years ago

Question 93

What was the extent of maximum ice cover in the northern hemisphere during Pleistocene?

Answer 93

Around 20,000 years ago 30% of the Earth's land surface was covered by ice 70m km3 of ice over North America, Europe and Asia

Question 94

What is the present ice cover?

Answer 94

About 10% of the Earth's land surface is covered by ice | The only ice sheets are the ones in Greenland and Anarctica

Question 95

What three main sources of evidence for changing global temperatures?

Answer 95

Chemical evidence, geological evidence and fossil evidence

Question 96

What is the chemical evidence for changing global temperatures?

Answer 96

The chemical composition of ice and marine sediments change as temperature changes, so they can be used to work out how global temperature has changed in the past. Ice and sediments build up over thousands of years so samples taken at different depths show the temperature over thousands of years. The records show a pattern of increasing and decreasing temperature, which caused the ice to advance and retreat.

Question 97

What is the geological evidence for changing global temperatures?

Answer 97

Some landforms we can see today were created by glaciers in the past - this shows that areas that aren't covered in ice today were covered in the past, which means temperatures were lower

Question 98

What is the fossil evidence for changing global temperatures?

Answer 98

The remains of some organisms are preserved when they die, creating fossils. Fossils show the distribution of plants and animals that are adapted to warm or cold climates at different times in the past - from this we can tell which areas were warmer or colder in the past