The Coastal System Flashcards
What type system is a coast? What does this mean?
Open - matter and energy can be transferred across the boundary of a system.
Name some: stores, inputs and outputs of a sediment cell.
Stores=beaches,cliffs,dunes,marshes. Inputs=rivers,glaciers,cliffs,sea floor.
Outputs=humans, waves (in theory, sediment not transferred out of the sediment cell).
How many sediment cells are in Wales and England?
11
Coasts are in (or trying to be in) dynamic equilibrium. Describe what this means.
Things are always changing, but if one element changes, there should be a corresponding change to another element.
Name and describe the four coastal zones, from furthest away from the sea to the closest.
Which zones make up the “near shore”?
(cliff)
Backshore - Area between HWM and landward limit of marine activity. Most changes here are due to storms.
Foreshore - Area between HWM and LWM. Most important zone for marine processes.
Inshore - Area between LWM and point where waves have no influence on the land beneath them.
Offshore - Area past point where waves have no influence on land beneath them. Only activity is deposition.
Foreshore and Inshore
What is the main driver behind waves?
Wind
How does wind create waves? What is this process called?
Frictional drag. Where wind blows over the sea to create waves. The larger the fetch, the greater the magnitude and energy of the wave.
What motion are particles blown in when waves are created?
Circular motion in direction the wind is blowing.
Describe the cross-profile of a constructive wave.
Longer wavelength, strong swash, weak backwash, 6-10 wpm.
Friction from bed disrupts wave particle circular movement, becomes more eliptical.
“Spills”.
Describe the cross-profile of a destructive wave.
Shorter wavelength, taller, strong backwash, weak swash, 11-14 wpm.
“Plunges”.
What is wave refraction?
Waves bending as they travel through different depths of water.
