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/the-water-cycle/2148.html http://www.bbc.co.uk/learningzone/clips/the-hydrological-cycle/406.html

Which words did you get? Precipitation Evaporation Evaporate 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 supply In a table with “economic”, “social” and “environmental” headings, put the following statements in the correct column. Unreliable rainfall Increasing population (migration or natural change) Agricultural demand (for crops etc) Pollution from agriculture and factories Rising living standards (more showers, dishwashers…) 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 Question a) Use the diagram to state two humans cause water scarcity through pollution. (2 marks) b) Explain ways people can overcome water scarcity. (4 marks)