GCSE Geography

GCSE Geography

Extreme Environments

Deserts Revision Pack

Name: Teacher:

Deserts Checklist:

Key idea (from specification) / Notes completed in book / Revision notes completed
Extreme environments have specific characteristics
People react to extreme environments in different ways
What a hot desert physical environment is like.
Hot deserts have an impact on humans.
Hot deserts are found in particular areas of the world.
There are hot desert areas on most continents.
Location of hot deserts is influenced by a variety of physical factors.
Temperatures reach extremes of hot and cold.
Precipitation levels are low.
Physical processes of weathering, erosion, transportation and deposition form distinctive hot desert landforms.
Ecosystems in hot deserts are finely balanced.
Plants have adapted to survive in hot deserts.
Animals have adapted to survive in hot deserts.
Hot deserts are used by a variety of people for different reasons.
Indigenous people have both positive and negative impacts on hot desert environments.
Hot deserts can provide valuable energy and mineral resources that can be exploited.
Hot deserts pose many challenges to different groups of people who live, work and travel in them and they are dealt with in different ways.
A variety of physical and human factors can cause desertification.
These challenges are managed in a variety of ways.
Hot deserts can be managed sustainably or unsustainably.
Climate change may have an impact in the future.

Key ideas studied in the first four weeks of this topic are shown in bold. The named hot desert environment you have studied is the Sahara Desert.

Enquiry Question: What do we mean by ‘extreme environments?’

Key ideas:

Extreme environments have specific characteristics
People react to extreme environments in different ways

Content:

• Understanding of various factors that define an extreme environment: difficult for people to survive, hazardous, unstable, remote, harsh climate and landscape.
• Different ways people have reacted to extreme environments over time

An extreme environment is…

I think that the most extreme environment on Earth is ______because…

People have reacted with awe to extreme environments in the past, for example…

Now people may see extreme environments differently, for example…

Enquiry Question: What do we know about hot deserts and how have they been represented in cultural resources?

Key ideas:

What a hot desert physical environment is like.
Hot deserts have an impact on humans.
Hot deserts are found in particular areas of the world.

Content:

• Description of physical characteristics to include: temperature, rainfall, vegetation.
• Description of human factors to include: population density, people who live and work in hot deserts, economic activity.
• Analysis of film, photographs, travel writing and poetry.

Deserts fact file:

Description (including figures) / Sahara example
Temperature
Rainfall
Vegetation
Population density
People who live there
People who work there
Economic activity

Artists, writers, explorers and reporters have written about/drawn extreme environments.

An example of a film set in an extreme environment is ‘The Mummy’ which is set in the Sahara desert. This was a good setting for this film because…

An example of a travel writer who has written about the desert is…

This photograph is called ‘Toureg in Niger’. It shows…

This poem represents the desert as…

Enquiry Question: Where are hot deserts found?

Key ideas

Hot deserts are found in particular areas of the world.
There are hot desert areas on most continents.
Location of hot deserts is influenced by a variety of physical factors.

Content:

• Global distribution of hot deserts, in relation to continents and lines of latitude.
• Location of the Sahara, Arabian, Australian, Kalahari, Thar, Atacama and Mojave.
• Understanding of physical factors including pressure systems, trade-winds, rain shadows and ocean currents.

Where are hot deserts found?

Hot deserts are found along the latitude lines known as:

1)

2)

Hot deserts are usually found on the ______side of continents.

The main hot deserts are found in the locations shown below:

Diagrams to explain the physical factors which influence the location of hot deserts:

Deserts are found along the tropics because of the global circulation system. Warm moist air rises at the equator, where there is a lot of rain. The dry air descends at the tropics… / Trade winds also contribute to the formation of deserts by…
Deserts can also sometimes be found in the rain shadow of mountain ranges because… / They can also be found in coastal areas with cold ocean currents because…

Enquiry Question: What are hot desert climates like?

Key ideas:

Temperatures reach extremes of hot and cold.
Precipitation levels are low.

Content:

• Diurnal temperature range and evaporation rates
• High pressure belts and intermittent/low rainfall.

Climate is the average weather recorded in a place.

The climate of the hot desert varies over the year. The graph above shows that the average monthly temperature never drops below ______and at its highest reaches ______.

Deserts are dry – they usually have less than 400mm of rain in a year. The graph above shows no rain at all for the months of…

Why are hot deserts so hot?

Hot deserts are hot because they are on the tropics and so the sun shines directly onto them.

Why are deserts so cold at night?

Why are deserts so dry?

They are dry because air is coming down onto the tropics, so it starts off cool and gets warmer and doesn’t cause rain.

Enquiry Question: What are hot desert landscapes like?

Key ideas

Physical processes of weathering, erosion, transportation and deposition form distinctive hot desert landforms.

Content:

• Exfoliation, freeze thaw, salt crystallisation and hydration.
• Physical processes responsible for the formation of the following landforms: sand dunes, wadi, yardang, rock pedestal, canyon, salt pan, mesa and butte.

Diagrams to show weathering processes:

Exfoliation / Freeze-thaw
Salt crystallisation / Hydration

What is the difference between weathering and erosion?

How does erosion shape the desert?

Wind –

Water –

Landforms fact file:

Landform / Description/Diagram / How does this landform form?
Sand dune / If there is a supply of loose ______and a strong enough wind the ______will be lifted by the wind. When it reaches a rock or a bush the ______will be dropped in the sheltered area behind it, making a dune.
Wadi / Rain may only fall once or twice a year in the desert. When the rain falls a ______flows, cutting a channel through the desert. When the rain stops the ______soon dries up, leaving a dry channel or Wadi behind.
Yardang / There are harder and softer rocks in the desert – the softer rocks _____ more quickly than the harder rocks. When the rocks are in bands the softer rocks ______leaving behind bands of harder rocks as Yardangs.
Rock pedestal / When the wind blows sand it abrades (wears away) the rock it hits. The wind can only lift the sand to around 2 m off the ground, so lower rocks are more affected. This forms ______.
Canyon
Salt pan
Mesa
Butte

Examples of landforms found in the Sahara desert:

Enquiry Question: What characterises the ecosystem of a hot desert?

Key ideas

Ecosystems in hot deserts are finely balanced.
Plants have adapted to survive in hot deserts.
Animals have adapted to survive in hot deserts.

Content:

• Food chain and food web of a typical hot desert ecosystem
• Physical adaptations of plants including xerophytic and ephemeral
• Physical and behavioural adaptations of animals.

An ecosystem is…

A food chain is…

A food web is…

This food web shows how ecosystems in hot deserts are finely balanced.

For example…

Annotated diagram(s) to show how desert vegetation has adapted to suit the climate and environment:

Definitions:

Xerophytic –

Ephemeral –

Physical adaptation –

Behavioural adaptation –

Annotated diagram to show how camels have adapted to suit the desert climate and environment:

Enquiry Question: How do people use hot deserts?

Key idea:

Hot deserts are used by a variety of people for different reasons.
Indigenous people have both positive and negative impacts on hot desert environments.
Hot deserts can provide valuable energy and mineral resources that can be exploited.

Content:

• Understanding of how indigenous people, tourists and multinational companies use hot desert environments.
• Impacts of one named indigenous people on a named hot desert environment.
• Reasons for and impacts of natural resource exploitation.

How do people use hot deserts?

Indigenous people – The Bedouin, Sahara Desert

Annotate this drawing to show how the Bedouin lifestyle suits the desert environment. Add at least four detailed labels:

Complete the following fact file about Bedouin life:

Location
Religion
Nature of villages
Jobs done by men
Jobs done by women
Sources of income
Problems faced
Threats to their culture

Keywords:

Indigenous – people who have lived in an area for a very long time

Nomadic – people who move about rather than living in one place all the time.

What impact do the Bedouin have on the Sahara desert?

Tourism

Why do tourists visit the desert?

Name three desert locations that are popular with tourists:

1.

2.

3.

What are the good points about tourists visiting the desert?

What problems can tourists cause in the desert?

How can desert tourism be made more sustainable (eco-friendly)?

Multi-national companies – The energy industry

Algeria is a North African country which has reserves of oil and gas. The oil and gas is under the ground. Big companies such as Shell and BP set up oil rigs to get the oil and gas out of the ground, then pipelines carry it hundreds of kilometres to ports on the coast.

Complete the diagram below to show the disadvantages of using fossil fuels for energy:

How could solar power from the Sahara solve Europe’s energy crisis?

The desert is an ideal place for a solar farm because…

Enquiry Question: What challenges do hot deserts pose to people and how can they be overcome?

Key ideas:

Hot deserts pose many challenges to different groups of people who live, work and travel in them and they are dealt with in different ways.
A variety of physical and human factors can cause desertification.
These challenges are managed in a variety of ways.

Content:

• Challenges of: accessibility and transport, water supplies, extreme temperatures, drought, famine and desertification and how they are managed.
• Desertification: over cultivation, over-use of water for irrigation, over-grazing, removal of wood for fuel, population pressure and drought.
• The different ways that challenges of hot deserts are managed including a named example from a specific hot desert.

Challenges of deserts

Use text and images to show the challenges that deserts can pose and how they can be overcome:

Challenge / How can it be overcome?
Drought
Famine
Extremes of temperature
Accessibility & transport
Water supplies

Desertification

Desertification is when the land turns into desert because of human activities and climate change.

It could be because there are too many cattle grazing in one area, or there could be too many crops being grown on the land, taking all of the goodness out of it.

It is different from a drought because a drought is a long time without rain, but the land recovers afterwards. Desertification permanently damages the land.

Complete the table to show the causes of desertification.

Physical factors / Human factors

The Sahel is an area which is suffering from desertification.

How could you describe the location of the Sahel?

Using a diagram, show what Excellent Development is doing to tackle desertification in Kenya. Remember to include the three stages:

1. Sand dams – store water in sand behind a dam
2. Terracing – flat areas cut into slope to stop soil erosion
3. Afforestation – trees are planted to hold the soil in place

This is an example of APPROPRIATE TECHNOLOGY. What does this mean?

Enquiry Question: What are the alternative futures for a specific hot desert environment?

Key ideas:

Hot deserts can be managed sustainably or unsustainably.
Climate change may have an impact in the future.

Content;

• Sustainable management – sustainable farming methods, afforestation, sustainable energy (solar power) and eco-tourism.
• Unsustainable management – population pressures, culture conflicts and resource pressures.
• Increased desertification of areas surrounding desert.

CASE STUDY: SAHARA DESERT

Evidence that the Sahara is being used in unsustainable ways:

Sustainable management initiatives in the Sahara:

What do you think the future holds for the Sahara? Remember to justify the points you make.

Deserts Glossary:

Adaptations –

Accessibility –

Butte –

Canyon –

Climate –

Climate change –

Continent –

Deposition –

Desertification –

Diurnal variation –

Drought –

Economic activity –

Eco-tourism –

Ecosystem –

Ephemeral –

Erosion –

Evaporation rate –

Exfoliation –

Extreme environment –

Famine –

Food chain –

Food web –

Freeze thaw –

Hazardous –

Hydration –

Indigenous people –

Intermittent rainfall –

Irrigation –

Latitude –

Mesa –

Multinational company –

Natural resources –

Rain shadow –

Remote –

Rock pedestal –

Ocean current –

Over cultivation –

Physical characteristics –

Population density –

Population pressure –

Pressure system –

Salt crystallisation –

Salt pan –

Sand dune –

Sustainable management –

Temperature –

Trade wind –

Tropics of Cancer and Capricorn –

Unstable –

Vegetation –

Wadi –

Weathering –

Xerophytic –

Yardang –

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