Coasts As A System Flashcards
What are waves
Waves are the movement of energy through water
How are waves formed
Waves are caused as wind blows across the surface of the water. This friction causes ripples which become tougher, allowing the wind to grip the roughened surface and intensify the wave
Fetch
The distance over which the wind has blown
Why do waves break
When waves become more elliptical (circular) in movement, friction slows down the base of the wave, causing the crest of the wave to rise as it moves forward. The wave steepens to a height of 1:7 and allows the wave to break as the velocity and wave length decrease
Crest
Highest point of a wave
Trough
Lowest point of a wave
What is the littoral zone
The near shore area where sunlight penetrates all the way to the sediment, allowing aquatic plants to grow
Back shore
The area between the high water mark and the landward limit of marine activity. Changes normally take place here during storm activity
Foreshore
The area lying between the high water mark and low water mark. Most important for marine processes in times not influenced by storm activity
Inshore
The area between the low water mark and the point where waves cease to have an influence on the land beneath them
Offshore
The area beyond the point where waves cease to impact upon the sea bed and in which activity is limited to deposition of sediments
Sediment cells
A length of coastline within which the movement of sediment is largely self-contained
Features of sediment cells
They vary in size, with the later cells being divided into sub-cells
Is a coastline open or closed?
Open system because inputs are received and outputs are transferred across the boundary across the boundary of the system
