Unit 1 Dynamic Planet Revision

Topic 4: Waterworld

What you need to know

• The hydrological cycle• Why some areas have unreliable water supply• How too little or too much water affects people• How humans affect water quality and quantity• How climate change affects the water cycle• Large scale water management example• Intermediate technology water management

example

The Hydrological Cycle

• As you watch the clips, write down at least 3 key words from each clip.

• Clip links:• http://www.bbc.co.uk/learningzone/clips/th

e-water-cycle/2148.html• http://www.bbc.co.uk/learningzone/clips/

the-hydrological-cycle/406.html

Which words did you get?

• Precipitation• Evaporation• Interception• Surface runoff• Percolation• Throughflow• Infiltration• Groundwater flow• Storage

• Evaporate• Water vapour• Condenses• Droplets

Practice Question (2 mins, 4 lines to write): The diagram shows the hydrological cycle.

State how 2 processes will be affected if there is a long, hot and dry summer. (2 marks)

Possible answers (For 2 marks you need 2 correct statements)

• There will be more evaporation

• There will be less precipitation

• There will be less percolation

• There will be less throughflow

• etc

Comparing climates

• How is rainfall shown?• How is temperature shown?

• Compare the climate graphs (similarities and differences)

What biomes would you expect to find in these places?

Reasons for an unreliable water supplyIn a table with “economic”, “social” and “environmental”

headings, put the following statements in the correct column.

1. Unreliable rainfall

2. Increasing population (migration or natural change)

3. Agricultural demand (for crops etc)

4. Pollution from agriculture and factories

5. Rising living standards (more showers, dishwashers…)

6. Climate change affecting rainfall patterns

Ex: Which of these affects water quality rather than quantity?

You must know the difference:

PHYSICAL WATER SCARCITY =

Demand > availability eg SW USA

ECONOMIC WATER SCARCITY = supply available but people can’t afford to exploit them. Lack of money to build storage facilities or distribute water eg Sahel

Economic Water Scarcity Case Study: The Sahel

Where?

Write the title

and describe

the location

of the Sahel.

Draw the table:

Causes of water scarcity Impact on people/ their responses

Fill in the table as you watch these clips.

• http://www.bbc.co.uk/learningzone/clips/expansion-of-the-sahara-desert/1500.html

• http://www.bbc.co.uk/learningzone/clips/burkina-faso-local-impact-of-desertification/4323.html

Physical Water Scarcity Case Study: The Sonoran Desert, SW USA

Why is the area facing water scarcity?

Effects of the lack of water

Fill in the table as you watch these clips

• http://www.bbc.co.uk/learningzone/clips/the-sonoran-desert-under-threat/3098.html

• http://www.bbc.co.uk/learningzone/clips/the-sonoran-desert-over-extraction-of-water/3099.html

Practice Question

• Explain some social and economic effects of water scarcity. (4 marks)

Water Management – Large Scale Example

• Large Scale: top-down project, expensive, big impacts on people, economy environment (good and bad)

Dam example: Katse Dam, Lesotho

1. Watch the clip writing at least 2 advantages and 2 disadvantages.

• http://www.bbc.co.uk/learningzone/clips/the-advantages-and-disadvantages-of-dams/539.html

2. Are your (dis)advantages social, economic or environmental?

Water Management – Intermediate Technology Example

• Intermediate technology = cheap, suits the local climate, landscape people, easily repaired, local people involved.

Intermediate Technology: Playpumps, South Africa

• http://www.youtube.com/user/1difference#p/search/19/mAfuKPItFQw

• What is the scheme?

• What are its advantages and disadvantages?

Practice Questiona) Use the diagram to state two humans

cause water scarcity through pollution. (2 marks)

b) Explain ways people can overcome water scarcity. (4 marks)