3.3

• What causes waves?

  Waves are mainly caused by wind blowing over the surface of water, creating frictional drag that produces movement in the water. Water particles move in circular orbits as waves pass.
• What is the relationship between wind speed and wave size?

  The size of waves is related to wind speed. Stronger winds generate larger waves as they build up over time.
• How do water particles move in waves?

  Water particles move in a circular orbit as waves travel across the surface, creating a ripple effect.
• What are swell waves?

  Swell waves originate in mid-ocean and can travel long distances. They appear as larger waves mixed with smaller, locally generated waves on coasts like the UK.
• What is "fetch" in relation to waves?

  The fetch is the distance of water over which wind-generated waves travel. The longer the fetch, the larger the waves can become.
• What are constructive waves?

  Constructive waves are low, surging waves with long wavelengths. They have a strong swash and weak backwash, leading to beach gain.
• What are destructive waves?

  Destructive waves are high, plunging waves with short wavelengths. They have a weak swash and strong backwash, leading to beach loss.
• How do waves affect beach morphology?

  Beaches change shape based on wave action. The material along a beach varies in size and type, depending on its distance from the shoreline, influenced by the waves' power.
• What happens when constructive waves reach the shore?

  Constructive waves deposit larger material at the top of the beach, forming a berm. The swash is strong, and the backwash is weak.
• What happens to beach material as the berm builds?

  As the berm builds up, the backwash weakens, and beach material becomes smaller as you move towards the shoreline.
• How do destructive waves affect the beach in winter?

  In winter, destructive waves, with their strong backwash and plunging nature, erode the berms created by constructive waves.
• What role does backwash play in beach morphology?

  The backwash of destructive waves can transport sediment offshore, forming offshore bars, and exert an undertow, pulling sediment back as the next wave arrives.
• What are offshore bars?

  Offshore bars are sediment deposits formed by strong backwash that carries material away from the beach.