Coastal Systems And Landscapes (Booklet 1) Flashcards
What is the atmosphere?
The air that surrounds the earth, made up of gases and water vapour.
What is the lithosphere?
The crust and uppermost mantle; this constitutes the hard and rigid outer layer of the Earth. This layer is split into a number of tectonic plates.
What is the hydrosphere?
A discontinuous layer of water at or near the Earth’s surface. It includes all liquid and frozen surface waters, groundwater held in soil and rock, and atmospheric water vapour.
What is the biosphere?
The total sum of all living matter. The biological component of the Earth’s systems.
What is a systems approach?
A model used to help explain phenomena such as a coastal environment.
What is an isolated system?
There is no input or output of energy or matter. Some suggest that the universe is the sole example of this type; others claim the idea is not applicable in geography.
What is a closed system?
There is input, transfer and output of energy but not of matter (or mass).
What is an open system?
Most environmental systems are open. There are inputs and outputs of both energy and matter.
What is a store/component?
A section of a system in which matter can remain, be added to or removed from.
What is a flow/transfer?
Movements between stores/components in a system.
What is a boundary?
The edge of a particular system.
What is dynamic equilibrium?
When the inputs and outputs in a system are balanced and the stores stay the same.
What is feedback?
Occurs when a system changes because of an outside influence. This will upset the dyanamic equilibrium, or state of balance, and affect other components in the system.
What is negative feedback?
When a system acts by lessening the effect of the original change and ultimately reversing it.
What is positive feedback?
Occurs within a system where a change causes a further, or snowball effect, continuing or even accelerating the original change; the effects are amplified.
What are some examples of inputs in a coastal system?
Energy from:
- waves
- winds
- tides
- sea currents
Sediment
Geology of coastline
Sea level change
Name some components of coastal systems?
Erosional landforms and landscapes.
Depositions landforms and landscapes.
Name some outputs of a coastal system?
Dissipation of wave energy
Accumulation of sediment above the total limit
Sediment removed beyond local sediment cells.
What is a back shore?
The area between the high watermark (HMW) and the landward limit of marine activity. Changes usually take place here only during storm activity.
What is the foreshore?
The area lying between the HWM and the low water mark (LWM). It is the most important zone for marine processes in times that are not influenced by storm activity.
What is inshore?
The area between the LWM and the point where the waves cease to have any influence on the land beneath them.
What is offshore?
The area beyond the point where waves cease to impact upon the seabed and in which activity is limited to deposition of sediments.
What is nearshore?
The area extending seaward from the HWM to the area where waves begin to break. It includes the:
Swash zone
Surf zone
Breaker zone.
What is the swash zone?
The area where a turbulent layer of water washes up the beach following the breaking of a wave.
What is the surf zone?
The area between the point where waves break, forming a foamy, bubbly surface and where the waves then move up the beach as swash in the swash zone.
What is wind?
Within the atmosphere, areas of high and low pressure form. In a low pressure area, the air is rising, which draws air in from higher pressure areas. This movement of air from higher pressure to lower air pressure areas is wind.
How are waves formed?
Air moves across the water. Frictional drag causes ripples. As the sea bed shallows, friction causes the base of the wave to slow down. The crest continues to rise, steepen and topple over.
What will effect the amount of energy provided by the wind?
The distance the wind has blown for (the fetch)
How strong the wind is
The duration for which the wind is blowing.
What is the wave crest?
The high point of a wave.
What is the wave trough?
The lowest point of the wave.
What is the wave height?
The height difference between the crest and the trough.
What is the wavelength?
The difference between successive crests.
What is the wave period?
The time in seconds between two successive crests or troughs.
What is the wave frequency?
The number of waves per minute.
What is the swash?
The movement of waves up the beach.
What is the backwash?
The movement of waves back down the beach.
What are swell waves?
Waves in open water, characterised by long wavelengths and reduced height. They can reach up to 15m high and can travel huge distances.
What are storm waves?
Waves generated by local winds which travel only short distances. (These are the waves you might see near the coast).
Describe constructive waves.
Distant weather systems generate these waves in the open ocean.
They are low, surging waves with a long wavelength. They have a stronger swash than backwash, meaning that build up the beach. The form on a gentle beach profile (over time the beach will build up and become steeper = negative feedback). The period between each waves is longer than for destructive waves.