Wave Action

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Wave Action

• 2/12
• Warm UP
• Which one hits the shore first?
• White cap or breaker

2

How Waves Form

• Wind causes the waves !
• Wind blowing across the water!
• Most waves form when winds blowing across the
  waters surface transmit their energy to the
  water.
• Wave size depends on wind strength, length of
  time the wind blows, and distance wind blows!
• Larger winds larger waves!

3
How Waves Form continued

• Only energy moves forward (the water in the wave
  moves in a circular motion)
• Deeper down smaller circular path

4
Anatomy of a Wave

• Check out the picture on your notes and label it
  accordingly!

Wave frequency of waves passing Wave height
wave energy/strength
5
Types of Waves (Breakers)

• When deep water waves get near shore, they begin
  to interact with the ocean floor. They then
  become shallow water waves.
• Near shore, the wave height increases and the
  wavelength decreases.
• Water near the bottom moves slower because of
  friction and causes the wave to eventually topple
  over (known as breakers)

6
Types of waves continued
7
How waves affect the shore!
What do you notice about the diagram????
8
Types of Waves continued

• Longshore Currents
• Waves hit the shore at an angle
• Erodes sediment and deposits it in other places

9
Types of Wavescontinued

• Undertow waves crash on the beach, water flows
  back to the sea underneath the incoming waves.

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Types of Wavescontinued

• Open Ocean Waves
• Whitecaps waves that break in the open ocean
  before they get close to shore. They are short
  lived and formed from stormy weather.
• Swells rolling waves far from shore. Can
  travel for thousands of kilometers.

WHITECAPS
SWELLS
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Types of Wavescontinued

• Tsunamis Created when a large amount of water
  is moved up or down from EQs, volcanic
  eruptions, landslides, underwater explosion, or
  meteorite impact.

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Types of Wavescontinued
Whats the picture showing? This is the
devastating tsunami of December 26, 2004 washing
ashore on the Thai island of Phuket.
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Types of Wavescontinued

• Storm Surges A local rise in sea level near the
  shore caused by strong winds from a storm.

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How waves affect the shore???

• Rip Currents
• A rush of water flows rapidly back to sea through
  a narrow opening.
• Sandbar traps water
• Can carry a swimmer into deep water ?
• How can you escape a rip current?
• Rip currents can be deadly

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How waves affect the shorecontinued

• Reducing Beach Erosion
• Over time erosion wears beaches away
• Look for ways to reduce the problem
• build wall rocks or concrete out from the beach,
  which is called a groin
• Groins increase erosion farther down the beach