1. Coasts Waves

8. How do you get waves like this ? 6R Giant Wave surfing.dv

9. How are waves created? Wind blows Friction Surface of the sea starts to move What do you think affects the size of waves? http://www.bbc.co.uk/scotland/education/geog/coastline/enhanced/

10. So wave size depends on: 1)Strength of wind 2)The fetch (the distance that a wave has travelled) http://www.bbc.co.uk/schools/gcsebitesize/geography/coastal/coastalpr ocessesrev1.shtml

11. What happens as the wave approaches the coast? (Read and see Waugh p300 Figure 18.1) Why does a wave break? What is swash and backwash? http://www.bbc.co.uk/scotland/education/geog/coastline/enhanced/ http://www.bbc.co.uk/schools/gcsebitesize/geography/coastal/coastalprocessesrev1.shtml

12. Destructive Waves They have a strong backwash compared to the their swash They are high in relation to the length of wave They are frequent waves (break at a rate of around 15 a min)

13. Constructive Waves They have a weak backwash compared to the their swash They are long in in relation to the height They are less frequent gentle waves (break at a rate of around 6-9 a min)

17. Sort the following facts. Are they about constructive or destructive waves? Weak swash & strong backwash Operate in calm weather Limited energy Steep beach angle High wave height (5-6 metres) Build up sediment on beaches Remove sediment from beaches Gentle sloping beaches Strong swash & weak backwash Cause erosion Break frequently (~15 per minute) Beach increases in size Low wave height (about 1 metre high) Much energy Operate in storm conditions Break less frequently (~7 per minute)