4c.1 Natures Fury

Question 1

Key variables (factors that can change)

Answer 1

• Wind speed
• Wind direction (determines distance travelled = fetch)
• Wave height (amplitude)
• Wavelength (distance between wave crests)
• Wave speed (number of wave crests per minute = frequency)
• Seabed
• shape/depth
• Swash strength
• Backwash strength
• Beach gradient
• Erosion
• Deposition

Question 2

Constructive waves

Answer 2

• Associated with light winds and short fetches
• Wave amplitudes (heights) are low, -wavelengths large
• Typically 6-9 wave crests per minute (low frequency)
• Swash is stronger than backwash encouraging deposition.
• Beaches are wide, shallow with beach berm created

Question 3

Destructive waves

Answer 3

• Formed by strong winds blown over long fetches
• Wave amplitudes (heights) are large, wavelengths short
• Typically 11-15 wave crests per minute (high frequency)
• Backwash is stronger than swash encouraging erosion.
• Beaches are narrow, steep but deposit offshore to form bar

Question 4

How storms effect waves?

Answer 4

When there is a storm, mind speed can rise forming larger waves. These waves can become destructive waves