Mountains and Deserts Revision Pack · 2012-05-18 · mean that they can form features such as volcanoes, Fold Mountains , deep-sea trenches and earthquakes. There are two main types

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Mountains and Deserts

Year 10 Extreme Environments

Revision Pack

Name:

Teacher:

Exam Date: 14th June 2012

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UNDERSTANDING THE QUESTION GCSE Geography - Command Words

When completing your GCSE Geography exam you must read the question carefully and answer it in the right way to make sure that you get as many marks as possible. Command words tell you what to do, i.e. what type of answer the examiner wants Always use geographical terms in your answers e.g. compass directions, use the scale of the map, give grid references.

Annotate - add notes or labels to a map or diagram to explain what it shows.

Here are some of the command words that you may be given:..

Compare - look for ways in which features or places are similar or different. e.g. a city in an LEDC compared to a MEDC

Complete - add to a map or graph to finish it off.

Contrast - look for the differences between features or places. Often the question will ask you to compare and contrast.

Define - explain what something means e.g. freeze-thaw.

Describe - give details about what a map or diagram shows.

Discuss - usually wants a long answer, describing and giving reasons for or explaining arguments for and against.

Draw - a sketch map or diagram with labels to explain something.

Explain or account for - give reasons for the location or appearance of something.

Factors - reasons for the location of something such as a factory.

Give your ( or somebody else’s) views- say what you or a particular group think about something , for example should limestone quarries be allowed in the Peak District.

Identify - name, locate, recognise or select a particular feature or features, usually from a map, photo or diagram.

Mark - put onto a map or diagram.

Name, state, list - give accurate details or features.

Study - look carefully at a map, photo, table, diagram etc. and say what it shows.

With reference to /refer to examples you have studied - give specific details about your case studies. E.g. with reference to a mountain area you have studied...

With the help of/using the information provided - make sure you include examples from the information, including grid references if it is a map.

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Exam Checklist – What do you know, what do you need to revise?

Checklist for revision

Introduction to Extreme Environments Understand and know

Need to do more revision

Do not understand and need teacher to explain

I can define an extreme environment

I can give examples of extreme environments

I can what challenges an extreme environment may present

I can discuss whether there are areas of extreme environments in Britain

Checklist for revision

Desert Environments

Understand and know

Need to do more revision

Do not understand and need teacher to explain

Notes

I can describe the environment of a hot desert

I can name at least 8 major hot deserts across the world

I can describe and explain the distribution of deserts around the world

I can describe the key climatic characteristics of hot deserts

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I can interpret climate graphs

I can describe what it is like to experience a hot desert climate

I can describe and explain effective desert survival techniques

I can describe real desert plants and explain how it is adapted to the hot desert

I can describe real desert animals and explain how it is adapted to the hot desert

I can name at least 6 physical landforms that are found in hot deserts

I can name and describe three types of weathering

I can define erosion and describe the two ways it happens

I can describe the process of deposition

I can describe and explain in detail, with the use of a sketch how a landform is formed

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I can describe at least three ways humans can utilise deserts

I can describe how people meet the challenges of deserts

I can define desertification

I know an area at risk of desertification

I can describe and explain the physical and human causes of desertification

I can name and describe ways of reducing desertification

I can describe and explain how cultures may disappear as deserts spread

I can name and describe how a

resource has helped me to understand

deserts more

e.g. poems, films, documentaries etc.

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Mountain Environments Checklist for revision

Understand and know

Need to do more revision

Do not understand and need teacher to explain

Notes

I know where the worlds major mountain ranges are found.

I can describe the location of the Himalayas

I can describe the characteristics and features of mountain environments

I can describe and explain the how fold mountains are formed in relation to plate tectonics

I can describe and explain how mountains influence weather and climate in an area

I can interpret and describe climate graphs for mountain areas

I can describe real mountain animals and explain how it is adapted

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I can describe and explain the formation of key physical features e.g. avalanches, glaciers, arêtes, pyramidal peaks, corries

I can describe at least three ways humans can utilise mountains

I can describe and explain effective mountain survival techniques and/or equipment

I can outline the causes, impacts and solutions to the effects of changes in the Himalayas e.g. climate change.

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Mountain Extreme Environments 1). Locations of large mountain ranges.

Watch this clip...http://www.bbc.co.uk/learningzone/clips/mountain-ranges-around-the-world/8423.html A). Label the map below to show where at least three mountain ranges are located. Can you remember the highest mountain in that range?

B. Describe the relationship between mountain ranges and plate boundaries (as shown on the map below):

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2. The Formation of Mountains

A. What plates push together to form...

• The Andes - • The Himalayas - • The Alps -

Information:

The Earth's crust is made up of seven principal tectonic plates and numerous other smaller plates. The plates are sections of the crust that "float" on the mantle, which is made up of molten rock. Where the plates meet, huge forces mean that they can form features such as volcanoes, Fold Mountains, deep-sea trenches and earthquakes.

There are two main types of tectonic plate. Oceanic crust is often only about 5km thick, but is very dense. Continental crust is considerably thicker, often being approximately 30km deep, but is less dense. Fold Mountains form on either Destructive or Collision plate boundaries.

Some plates move apart, others push together. The ones that push together are called CONVERGENT plate margins. This kind of boundary destroys the plates as they crush together, either by melting them if they get pushed underneath (DESTRUCTIVE plate margin) or crumpling them up (COLLISION zone or plate margin).

Destructive Where an oceanic plate moves towards a continental plate. Because the oceanic plate is heavier it subducts under the continental plate.

Volcanoes and earthquakes. Fold mountains

South American plate & the Nazca Plate

The Andes Mountain range and volcanoes.

Collision Where two continental plates move towards each other.

Fold mountains Indo-Australian plate & Eurasian Plate

Construction of the Himalayan Mountains

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Case Study The Himalayas http://www.youtube.com/watch?v=7gXixxYKM80&NR=1

The best example of a collision plate boundary is found where the Indian plate collided with the Eurasian plate to form the Himalayas.

• The Himalayan mountain range is found on the border of Nepal and China, North of India through to Afghanistan in the west.

• Mount Everest is the world's highest mountain at 8,848 metres above sea level (asl)

What ultimately formed Mt. Everest, about 60 million years ago, was the rapid movement of India northward toward the continent of EuroAsia. India charged across the equator at rates of up to 15 cm/year, in the process closing an ocean named Tethys that had separated fragments of Pangea. This ocean is entirely gone today, although the sedimentary rocks that settled on its ocean floor and the volcanoes that fringed its edges remain to tell the tale of its existence.

What is the rock formation, climbers call the ‘yellow band,’ just below Everest’s

summit? How does this help explain how Everest was formed?

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B. Explain how Fold Mountains form.

Draw a diagram to show how Fold Mountains form:

Label the type of plate boundary this shows and make sure you annotate the diagram.

Write a paragraph to explain why mountains are often found along this type of plate boundary:

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Climate graph for Kathmandu, Nepal

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3. The Mountain climate [Page 48 of the Geography textbook].

A. Fill in the missing gaps to the key statements.

http://www.gknmissioneverest.com/includes/weather/weathertop.htm

• The higher the altitude (the height above ______), the _________ it gets and the thinner the atmosphere becomes (the amount of _______ in the air). The temperature falls roughly 0.6C for every 100 meters you go up.

• Mountains force air to ___________ and _____________, forming clouds. Rain or snows are more likely through ‘__________ rainfall’.

• Mountains act as a _____________ to wind. Weather on the windward side can be different from weather on the leeward side.

• Different sides of the mountain receive light from the ___________ at different times.

B. Describe the annual temperature patterns in Kathmandu, Nepal.

C. Describe the annual precipitation patterns in Kathmandu, Nepal

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4. Glaciers The Glacial system Just as a river could be seen as a system of inputs, outputs, transfers and storage, so can a glacier. Whether a glacier grows or retreats is directly affected by the comparison between the inputs and outputs.

Glaciers originate from heavy snowfalls over a prolonged period of time. The snow initially has many air or pore spaces between the flakes. Over time the weight of new snow above it compacts it all, squeezing the air out of

the pore spaces, similar to what you might do when making a snowball. This compaction causes some of the snow to become freezing water that binds the compacted snow together even more, creating ice (Firn). As the air is squeezed out of the ice it will turn a slight shade of blue (Neve) A. Copy diagram B on page 51 of the Textbook. Make sure you give it a title and label it fully.

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5. Glacial Weathering and Erosion.

http://www.bbc.co.uk/schools/gcsebitesize/geography/glaciation/

http://www.youtube.com/watch?v=ravQqTkcD8I

Glacial Processes that shape landforms. There are three main types of glacial processes - plucking, abrasion and freeze thaw.

Freeze-thaw is when melt water or rain gets into cracks in the bed rock, usually the back wall. At night the water freezes, expands and causes the crack to get larger. Eventually the rock will break away. Plucking is

when melt water from a glacier freezes around lumps of cracked and broken rock. When the ice moves downhill, rock is plucked from the back wall. Abrasion is when rock frozen to the base and the back of the glacier scrapes the bed rock.

Glacial Landforms - Upland Features Upland glacial features include: Corrie - This is an arm chair shaped hollow found in the side of a mountain, e.g. Lake Glaslyn, Snowdonia, Wales.

Arete - This is a narrow, knife edge ridge separating two corries, e.g. Crib Goch, Snowdonia, Wales.

Pyramidal Peaks - These are formed when three or more corries form in the side of

one mountain, e.g. Mount Snowdon, Snowdonia, Wales or Mount Everest.

A. Name three other glacial landforms and describe what they look like.

1).

2).

3).

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B. Describe a glacial landform and explain the processes that have created the landform. [Do not repeat information – ‘Corrie’ is the model example]

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__________________________________________________________________________________________________________________________________________________________________________

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6. Animal and Plant adaptations

http://www.youtube.com/watch?v=jSGikymKFlc

A. Draw an annotated sketch of a mountain plant or animal, explaining how it has adapted to the mountain environment.

7. Sources of information

A. Describe one source of information you have used whilst studying extreme environments [Mountains], and explain how it has helped you to study this topic.

Source: Touching the void Documentary

____________________________________________________________________________________________________________________________________________________________________________________________________________

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8. Climbing Mount Everest, Himalayas

A. Describe & Explain four reasons why Mount Everest is a challenging environment.

1).

2).

3).

4).

B. Draw four items that you would take with you on an expedition to Mount Everest and explain why you would take that item.

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9. Pressures on mountain environments

Who uses mountains?

• It wasn't until 1953 that the summit of Mount Everest was finally conquered. Since then, hundreds of expeditions have set out to climb to the top. Although many have been successful, the mountain has also claimed many lives.

• More people can afford to travel to remote areas. PROBLEMS

• Expeditions set up their base camps lower down the mountain. This means that literally hundreds of people visit the mountain every year. As a result, large amount of rubbish gets left behind - plastic, papers, abandoned tents, equipment, oxygen bottles etc. Mount Everest is called the dirtiest mountain in the world.

• An added problem is that, because of the extreme cold, very little material rots away (biodegrades). E.G in 1999 of the body of George Mallory was discovered ...he had tried to climb Everest in 1924!

SOLUTIONS • People were so worried about the build up of rubbish that in 1994 an

expedition set out just to clean up the mountain. They cleared away a lot of rubbish and also set up a program to remove old oxygen bottles.

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10. Information - The Porters who carry heavy loads in the Andes. Porters are essentially people from South America who carry heavy loads up the Andes mountains for hikers. It is only because of these porters that people have been able to finally reach summits that had long seemed unattainable.

In the modern age of mountain climbing, porters are among the most accomplished mountaineers. They often serve as guides to foreign climbers, and the names of their own great mountaineers hold a high place in mountain lore.

Such feats, along with their continued roles in carrying loads, fixing ropes, setting camps, and generally tending to climbing teams have earned the Sherpa people a place of unequalled respect. They've also helped to create a climbing and trekking industry that has brought the world to the South America region.

Some of these porters have suffered ongoing back problems due to heavy packs and long distances along the INCA trail.

Tasks: 1). Describe what a Peruvian Porter does. 2). Explain why these men become porters. 3). Suggest what life may be like for these porters.

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11. Climate Change and Mountains There are many important glaciers in the Andes mountain range.

• The mountain range locks away large volumes of frozen water.

• The glaciers of the Andes feed the giant rivers of Peru and Chile, and support many people who depend on them for drinking water and irrigation for farming.

Climate change is thought to be melting glaciers. This will have Local, National and Global effects. It will change how local economies earn their money, how and where people live (Social) and have drastic effect on the environment.

A. Draw a diagram to show how greenhouse gasses are thought to be causing climate change. Annotate the diagram in detail.

B. State two pieces of evidence that climate change is taking place: 1. 2.

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C. Think about the effects Climate Change will have Economically, Socially and Environmentally. Create a Brainstorm to show the effects. THINK MELTING GLACIERS, FLOODING, DRY INFERTILE LAND, ELECTRICITY LOSS, DRINKING WATER.

D. Exam question: Explain how climate change will affect the natural environment of the Andes Region in the future. (6 marks)

___________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Affects of climate change on the Andes Mountains and surrounding

areas

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12. How people use the Mountains Tourism in mountains - The Andes attract lots of tourists both regionally and internationally. People visit the highlands for activities such as skiing, climbing, mountain-biking, hiking and hang gliding. People want to see Machu Picchu – the lost Inca city. It is a wonder of the world and a very popular tourist destination.

Advantages • This gives people who live in the settlements near the Andes an opportunity for

employment and brings wealth to the local people who provide them with accommodation and other services.

• A greater sense of purpose for people living in the area. • The tourism brings in chances for development such as schools and improved

healthcare in areas that are less developed such as Peru and Chile. • Improves local transport links with building of main roads and railway networks.

Disadvantages • Not everyone in local communities welcome tourists. Some fear interference with

their livelihoods (e.g. farmers). • Tourists cause congestion and pollution by bringing their cars and leaving rubbish

on hillsides. • Tourist developments like building ski lifts can spoil the landscape. • Too much recreational activity may damage fragile environments (eg soil erosion

can interfere with flora and fauna). • Deforestation occurs to cope with the tourist energy demands and for building

accommodation. • Tourists may not respect local cultures.

A. Complete the flow diagram to show how an increase in tourism would affect the Andes in the future.

Increase in Tourism

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Energy in mountains - Glacial valleys, with their steep sides and high rainfall, are ideal for damming to create reservoirs which will generate HEP. Advantages • Provides reservoirs to store clean drinking

water for people.

• Produces clean and renewable hydro-electric electricity for people and businesses.

• Creates local jobs and new opportunities for sports and businesses, such as fish-farming.

• Stored water can be controlled and irrigated to local farms in the region.

• Electricity can act as a catalyst to development because it can improve schools and health centres.

Disadvantages

• Damming has a major impact on local environments.

• Damming often leads to displacing large populations of people.

• Flooding valleys and altering the course of rivers prevents the landscape being used by farmers, tourists and wildlife and affects the water cycle.

• Dams and electricity pylons are considered by some to be blots on the landscape.

B. Complete the flow diagram to show how an increase in producing electricity via H.E.P would affect the Andes in the future.

Increase in H.E.P

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C. Exam Question – Describe how people use a named mountain environment and explain how this affects people living in that region. (6 marks)

___________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ __________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

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Desert Extreme Environments 1. The Location of hot deserts

A. Write down the key characteristics of hot deserts:

1).

2).

3).

B. Label the main hot deserts locations on the map below [At least 6].

The global distribution of deserts shows a clear pattern…

C. Add three important lines onto the map needed when describing the location of hot deserts. These lines are known as the:

1).

2).

3).

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2. The Climate of Deserts

A. Describe the temperature of the Sahara desert environment.

B. Describe the precipitation pattern of the Sahara desert environment.

C. Explain why is it hotter during the day, than at night in the desert.

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D. Explain how the desert is a hot and dry environment.

The desert is very hot because:

The desert is dry because:

[Give three examples on why a desert may be dry] Draw the diagram and explain the processes that are taking place that keep the desert dry.

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3. The challenges of the Desert

A. Describe the challenges you would face if you travelled across the Sahara desert and explain how you would overcome the problems.

Challenge Effects How could I avoid/ overcome this?

The deep, soft sand.

A normal car or vehicle would have a high chance of getting stuck in the sand.

Take a specialised vehicle to cope with the conditions. This could be a 4X4, quad bike or a more traditional camel.

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4. Sources of information to help you understand the desert environment.

http://www.youtube.com/watch?v=tFTpWy_gnVY&feature=related

http://www.youtube.com/watch?v=64wBr5JGAxk&feature=related

http://www.youtube.com/watch?v=EOvF4n7-5F4&feature=fvwrel

A. Give one example of how a desert has been depicted in a film, photograph, expedition/historical report, poem, painting, piece of music or literature.

B. Discuss how has this source of information has helped you to understand the desert environment.

5. Plant and animal adaptations to survive in the desert

A. Using the notes from your books annotate the adaptations of this Cactus and explain how they help it survive in the desert.

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B. Now close your book. From memory annotate the adaptations of this camel and explain how they help it to survive in the desert environment. [There are at least 8].

http://www.youtube.com/watch?v=YX8VQIJVpTg

Exam Tip – The exam question may be in written form rather than from sources or diagrams. Make sure you feel comfortable that you could answer it clearly. Look at this example:

‘Describe and explain how plants and animals have adapted to survive in hot deserts’.

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6. The Bedouin People

The Bedouin people are the people who have used the deserts for thousands of years. Look at page 32 and 33 in the textbook.

A. Complete the following fact file about Bedouin life:

Location

Religion

Nature of villages

Sources of income

Problems faced in the desert and ways they have overcome these problems.

Threats to their culture

B. Define the following Keywords:

Indigenous –

Nomadic –

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7. Desert Landforms

Remember that you need to know a wide range of desert landforms. However more importantly you need to understand the processes involved in shaping them. Focus on two or three landforms and make sure you know exactly how that landform was formed in the desert.

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8. Processes that shape desert landforms

Weathering and Erosion

Erosion As there is little vegetation cover, sand and soil can be easily eroded by both wind and running water, producing spectacular desert landforms.

In dry periods, winds blow loose sandy material away, leaving behind heavier rock and stones. Sand dunes are the result of the deposition of this finer material. Sand dunes occur in a variety of shapes and sizes.

When rain does occur, it is usually in the form of sudden, heavy downpours, which cause flash floods. The power of these storms removes all loose surface material, causing a number of different erosional landforms (such as mesas, buttes, wadis and badlands) and depositional landforms (such as alluvial fans).

Physical Weathering Block disintegration: Block disintegration involves sharp temperature changes, affecting the minerals within the rock, making desert rocks expand and contract.

Freeze Thaw Water enters cracks in the rock during the day. Overnight the temperature drops and the water freezes. As it freezes, it expands. The expanded ice places pressure on the rocks around it. Over time this constant pressuring of the rock causes it to crack and split.

Crystallization of salts: Crystallization of salts as a result of dissolved salts expanding as they dry split the rocks and honeycombs its surface.

Exfoliation or Onion Skin Weathering This type of erosion is common in desert areas. As the sun shines on rocks during the day it causes them to expand. During the night the rock contracts due to the colder temperature. Over time this continued process causes small pieces of surface rock to flake off.

The image shows a close up of onion skin weathering.

Biological weathering: Plant roots or animal burrows can cause rocks to disintegrate and break apart.

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A. Describe a desert landform and explain the processes that have created the landform. [Do not repeat information – ‘Rock Pedestal or a sand dune are the model examples, you must highlight the correct processes involved].

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9. People’s use of hot deserts

USE BY PEOPLE EXAMPLES

Farming

The Bedouin are a nomadic pastoralist people, and are inhabitants of the Sahara Desert. The Bedouin people’s traditional way of life is disappearing.

The Bushmen, San, Sho, Basarwa, or Khwe are indigenous people of southern Africa. They were traditionally hunter-gatherers.

Tourism

Dubai luxury resorts

Las Vegas luxury hotels and gambling

1 million tourists visited Namibia desert in 2008

Mining

The Taoudenni Salt Mines of the Sahara Desert. The salt was transported by camels to the market in Timbuktu, 150 miles to the south.

Gold mining in the Mojave Desert. – California gold rush.

Drilling for oil Libya is an important oil producer. The Sahara desert has large amounts of oil and gas ready to be extracted.

Renewable energy

Renewable energy such as solar panels are being introduced to large desert regions. A fraction of the Sahara desert would be needed to provide clean solar energy to the entire world.

Filming

The English Patient; Sahara; Star Wars; The Mummy; Lawrence of Arabia were all filmed in deserts. The Star Wars location in the Sahara, Tunisia has become a tourist destination.

Military Testing

Great Salt Lake Desert, USA is used for the testing of chemical and biological weapons.

Nuclear testing took place in the Nevada Desert, USA.

War and Conflict Operation “Desert Storm” and the Gulf War.

Conservation areas

Desert Elephant conservation in Namibia.

Simpson Desert Conservation Park and Regional Reserve in Australia, covering an area of more than 3.6 million hectares

Settlements

Dubai

Las Vegas

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A. Describe three major ways of using the desert.

1).

2).

3).

B. Pick one use and write a list of advantantages and disadvantages resulting from that activity in the desert. Then state if they are economic, social or environmental.

Activity:

Advantages disadvantages

C. Discuss ways in which the desert may be used in the future.

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Main exam question: Using photographs C, D & E and you own knowledge of named deserts which you have studied, describe the activities carried out by different groups of people in the desert. To what extent is it challenging for people to carry out these activities in hot deserts? [8 marks]

Model answer

People use the world’s desert in a variety of ways. As shown in photo A, Trans-national corporations (TNC’s) use the Sahara desert to extract oil because of it’s economic value. This can be a challenge because the desert is a very hot environment and it is difficult to complete such hard work in excessive heat.

As shown in photo B tourists use the Namib desert for recreational purposes. Lots of tourists go to the Namib desert to take part in adventure activities such as driving 4X4’s across sand dunes. This is challenging because the vehicles could get stuck in the deep sand and because the desert is remote and does not have many refuelling stations.

As shown in photo C, the Bedouin tribe live in the Sahara desert because it is a natural habitat for them and is part of their livelihood. The nomadic indigenous people use the desert for grazing animals and for water. It is challenging for the people to use the desert because the climate is very dry and there is not a lot of vegetation for the animals to graze from. People have adapted to make the most of the challenging desert environment.

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10. Desert Challenges - Desertification

Deserts are increasing in size daily. This is partly due to human actions. Poor farming techniques, such as overgrazing and over cultivation in areas of savannah grassland, are causing soil erosion and desertification. The flow chart below explains the process of Desertification.

EXAM TIP: Be accurate, use real examples, e.g. do you know the countries in the Sahel region. Why is this region under pressure?

Using the flow chart and your exercise books complete the following questions:

A. Explain what desertification is?

B. Describe where is it happening. Give a Case Study.

DESERTIFICATION

Increase in population Increase in cattle

Deforestation for fire wood Grassland grazed more intensively

Roots no longer hold soil together Roots may be eaten as well as grass

Leaves no longer protect soil from weather Less vegetation means less protection from weather

Loose top soil blown away by wind

(Soil Erosion)

Loose top soil blown away by wind

(Soil Erosion)

DESERTIFICATION

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C. Describe the causes of Desertification and link them to the Sahel case study:

1). Increased population pressures – 2). Overcultivation – 3). Overgrazing – 4). Deforestation – 5). Climate change -

Impacts:

What are the physical impacts?

• Soil erosion. • Sun baked, cracked soil. • Loss of plants and animals. • Gullying. • Dry rivers. • Growth of desert. • Increase in sand storms. • Flash floods.

What are the human impacts?

• Crops and cattle die, resulting in famine. • Death. • Migrants move to cities, resulting in the growth of informal settlements, shanties, in already

massively overpopulated urban areas. Over 2 million have migrated from Mali and Burkina Faso.

D. Describe and explain the possible solutions to overcome the challenge of desertification.

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Key words Glossary

Show you are a good geographer by using key words. Try to show you know what they mean in your answer. Give a full answer wherever you can.

Here are some key words and the context you can use them in. There are more than this so use a text book to help.

Word Definition Mountain Example Desert Example abrasion – the erosion of a surface cased by pieces of rock carried in rivers, glaciers or wind – like sandpaper.

“A U shaped valley is created as a glacier moves down a V-shaped valley. Ice has 10 times the erosive power of water. The weight of the ice acts like a giant bulldozer, removing much more of the valley sides and floor through plucking and abrasion” “rocks in stuck in the moving ice abrade the bedrock like sand paper”

“In deserts rocks are worn away by the wind. Abrasion is caused by particles of sand being carried by the wind causing a sandblasting effect” “Abrasion is greatest near the base of a pedestal rock. This is where the wind carries most sand as it lifts the particles of air off the ground”

Afforestation - the planting of trees

“Trees can be planted to secure the soil on mountain slopes. Afforested areas reduce flooding in mountain regions”

“Afforestation is used in deserts as a sustainable farming method. Trees protect the soil from wind and rain. Tree roots help bind soil together and prevents erosion”

alluvium - material deposited by a river

“ An alluvial fan is deposited by rivers as the foot of a steep mountain”

Alluvium is deposited on a wadi (desert valley) floor, most of the time they are dry and desert plants grow in on it”

altitude - the height above sea level

“The higher the altitude the colder it gets and the thinner the atmosphere becomes. Climbers suffer from altitude sickness.” “Mount Everests, in Nepal has the highest Altitude of 8850m asl”

arete - the ridge between two corries

“ice erosion, abrasion and plucking, create a sharp ridge where the back wall of two cirques cut back into the mountain”

boulder clay - rocks, sands and gravels deposited by melting ice; also known as till

braiding - the spitting of a river into different channels

“Rivers flowing from the snout of glaciers have more flow in the summer when there is more melting and less in the winter. This creates braided river channels where rocks are sometimes deposited in winter and moved by water again in summer”

climate - the average of the weather conditions, usually measured over 30 years

“The climate in La Paz,in the Andes, is affected by the altitude. Making it much colder”

“Timbuktu in Mali has a desert climate. Temperatures range from 25 to 35 degrees, it has a short season of rain” “a hot, dry climate which is generally experienced on the western sides of continents around 30 north and south of the equator”

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Word Definition Mountain Example Desert Example

Corrie / Cirque - a large hollow near the top of a mountain, caused by glacial erosion

“Snow accumulates in mountain hollows, snow is compressed into ice. As the ice moves erosion and weathering exaggerate the hollow creating a cirque or corrie”

Deflation – a form of desert erosion. It is the gradual removal of sand and dust to leave a flat surface or hollow in the rock.

“Blowouts are large hollows created by the process of deflation, when wind scoops up and removes the sand” “The flat tops of plateaus, mesas and buttes are created by deflation”

deforestation - the cutting down of trees

“Deforestation of mountain slopes can lead to soil erosion in heavy rain. Landslides are more common and make living in mountain regions more hazardous”

“Deforestation can increase soil erosion, this is a factor in desertification”

deposition - the dropping of rocks and other materials by e.g. glaciers, rivers and wind etc.

“Eroded material is deposited at the snout of the glacier as it retreats. This forms a ridge of terminal moraine”

“Wind carries fine particles of sand and deposits then as sand dunes” “During flash floods, desert rivers remove large amounts of material and deposit it further along the valley or across a flood plain.”

desert - an area with very low rainfall, usually less than 250 nun a year

“The Sahara is a desert in North Africa” “The Kalahari is a desert in South Africa”

Desertification – the process by which land turns into desert due to human activities and climate change.

Desertification is happening in many parts of the world. One of the worst affected areas is the Sahel region of Africa.

drought - a long period of dry weather

“Mountain regions can suffer from drought if the water is ‘locked up’ as ice”

“Vegetation can recover from long period of drought. In the Sahel this is the normal pattern”

erosion - the wearing away of soil and rocks by e.g. rivers , glaciers and wind

Glaciers erode the mountain valleys creating wide U-shaped valets when the glacier has melted, for example around Snowdon in Wales

“Rocks are eroded in deserts by the processes of deflation and abrasion.”

freeze-thaw action - the weathering process that breaks up rocks by the repeated freezing and thawing of water in cracks

“Freeze-thaw weathering occurs where temperatures in deserts fall below freezing at night. Moisture in cracks expands up to 10 times when frozen. Overtime the expansion can cause rocks to break, causing block disintegration.”

glacier - a mass of ice flowing down a valley

“The Gangotri Glacier is located in Uttarkashi District, Uttarakhand, India in a region bordering China. This glacier, source of the Ganga, is one of the largest in the Himalayas “

hanging valley - a smaller valley which hangs above the main U shaped valley in

“Once the glacier has retreated, rivers flowing along hanging valleys create waterfalls”

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Word Definition Mountain Example Desert Example a glaciated region Ice age - the long, cold period when ice and snow covered most of northern Europe

“Snowdonia is an extreme environment in the UK. Its landscape, popular with walkers and climbers, was created by glaciers and ice during the last ice age”

landform - a feature made by natural processes

“A corrie or cirque is an example of a glacial landform. It is created by...”

“An inselberg is an example of a desert landform. It is created by...”

lateral moraine - material found at the sides of glaciers

“Freeze thaw and plucking continues along the sides of a glacier as it advances. Eroded material at the side is called lateral moraine”

moraine - material deposited by glaciers

“When a glacier reaches the zone of ablation it melts, the rocks that were being carried by the glacier are left in a terminal moraine.”

outwash plain - the flat plain made up of material washed out of a melting glacier or ice-sheet

“Lots of rivers made from the melting ice will flow across the outwash plain. They can be very dangerous to cross.”

overpopulation - where too many people live in an area for the resources available, resulting in a low standard of living

“Mountain areas tend to be under populated rather than over populated”

“over population of cattle causes overgrazing. This strips away the vegetation and prevents it from growing back leading to desertification.”

physical landscape - the natural scenery of an area

“Moving around mountain areas can be extremely difficult due to the steep sided mountain slopes and valley sides. The physical landscape makes it difficult to build roads and rail routes.”

“The physical landscape in a desert can vary from areas of deposited sand such as dunes, to high flat topped mountains or mesa.”

plucking - the way by which moving ice pulls away rocks onto which it has frozen

“The back wall of a corrie (cirque) is made steeper by ice plucking away the rocks. This creates its ‘arm chair’ shape”

pollution - damage to the environment caused by people

“Rubbish left by climbers and tourists causes lots of pollution in low energy environments such as mountains”

“Oil and energy exploration in the desert can cause high levels of pollution”

pyramidal peak - a pyramid shaped peak made by glacial erosion

“Climbers often want to reach the summit or mountain peak. This is the sharp top to a mountain, often where three corries formed back to back”

rainfall pattern - the distribution of rainfall throughout a year

Mountains force air to rise and cool, forming clouds. Rain or snow are more likely” “Rainfall patterns are more predictable in mountains”

“Rainfall is unreliable and scarce. One heavy shower could be followed by months or even years without rain”

Sand dune migration – Movement of sand dunes

“Sand dunes appear to move over time as sand shift in the direction of the

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Word Definition Mountain Example Desert Example over time prevailing wind” Sand Dune- Mound of loose sand deposited by the wind

“A sand dune forms around and obstacle on the ground. The wind hits the object, loses energy and drops the sand it is carrying.”

scree - a pile of loose jagged rocks made by freeze-thaw

“Climbers and walkers have to be very careful when crossing loose scree as it is a hazard”

seasonal rainfall - is rainfall which occurs mostly during one part of a year

“The Sahel has seasonal rainfall, with rain only expected during may to august.”

shelter belt - a line of trees which reduces wind speed and thereby protects the crops and soil behind it

“Sustainable farming methods mean more crops for farmers. It uses simple techniques such as planting a shelter belt to combat the effects of desertification.”

temperature range - the difference between the highest and lowest temperatures

“Snowdon’s temperature range is 8 degrees centigrade” “La Paz has a temperature range of 2 degrees”

Deserts have a huge temperature difference between night and day. This diurnal range Can be from 40 degrees in the day down to below freezing at night”

transportation - the carrying of rock particles

“Eroded material is transported by glaciers and rivers down the mountains”.

“The wind carries lighter particles of sand and transports them in suspension. Sand is rarely carried more than a metre off the ground”

U-shaped valley - one that has steep sides and a flat bottom and has been over deepened by a glacier

“One a glacier has melted the remaining U shaped valley is very useful for farming. E.g. in Snowdonia”

V-shaped valley - a valley that has been eroded by a river

“Before glaciations valleys are steep sided and Vshaped”

“Steep V shaped Valleys form as fast flowing seasonal rivers cut through plateaus creating canyons.”

weathering - the process by which rocks are worn away but not transported away

“The mountain peaks are weathered in the extreme temperatures, causing the rocks to shatter and break up.”

“Insolation weathering caused by the heating of minerals in rocks during the day. Minerals expand and contract at different rates leasing to block disintegration”

IMPORTANT: Use your time wisely to revise. Do a little, a lot.