Starter: Spot the difference

Find six differences between the two pictures of Sam, Katie and Spike at the beach

• Learning Objectives

• What are the different types of wave?• Why are some waves bigger and stronger

than others?

http://www.youtube.com/watch?v=k2vkwy2vdP4

Why do waves break?

Waves are the result of the wind blowing over the sea. As they approach land they break.

The bottom of the wave touches the sand and slows down due to increased friction. The top of the wave becomes higher and steeper until it topples over.

Backwash

Swash

Note: Backwash is always at right angles to the beach

Swash and backwash

Why are some waves bigger than others?

Where do people go surfing in the UK?

Fetch

• The greater the distance over which the wind blows, the bigger and stronger the waves are.

Why are waves generally larger in the south west?

Wave energy depends on the fetch, the strength of the wind and the length of time over which the wind has blown.

fetch = the distance over which the wind has blown

http://www.youtube.com/watch?v=Vtpk-PknwCo&eurl=http://www.geographyalltheway.com/igcse_geography/natural_environments/marine_processes/wave_processes.htm

Which of these would give the biggest waves and why?

What about in the world?

PlaceGood surfin

g

Poor surfin

gReason

Blackpool

Newquay

Great Yarmouth

Bournemouth

The height of and strength of wavesdepends on 3 factors…1. Speed of the wind2. The length of time the wind blows for3. The length of water the winds blows over

(Fetch) – this is a useful definition and will impress examiners…

Types of waves

http://www.youtube.com/watch?v=EpFykGLsDnM&eurl=http://www.geographyalltheway.com/igcse_geography/natural_environments/marine_processes/wave_processes.htm

http://www.youtube.com/watch?v=FHvAxYrHdDU&eurl=http://www.geographyalltheway.com/igcse_geography/natural_environments/marine_processes/wave_processes.htm

Using the Materials provided and Geog. GCSE p88-89, Make a model and explain to the rest of the group the following

processes

Group 1: What causes Waves? Why do waves break?

Group 2: Why are some waves bigger and stronger?

Group 3: What is a Constructive Wave?

Group 4: What is a Destructive Wave?

Answer questions 1, 2, 3, 4, 5 from Geog. GCSE

Summary

What causes waves?Waves are caused by the friction of the

wind on the surface of the water

Why are some waves bigger than others?

Wind speedTimeFetch

Six-foot swells are set to break on the Thames at an attraction aiming to tempt the growing ranks of urban surfers to taste the "quintessential California

surf lifestyle" in the unlikely surroundings of a disused dock in east London.

From 2011, the world's first outdoor artificial surfing machine will try to rival the Atlantic

breakers of Devon and Cornwall using cleaned river water.

Which of these would give the biggest waves and why?