Environmental change & managment Flashcards
How are waves created?
Waves are created by wind blowing over the ocean. The friction from the wind causes the surface water to move in ripples which eventually form full waves. This is because the wind is transferring energy to the water, stronger winds transfer greater amounts of energy leading to larger waves.
What is wave refraction?
Wave refraction is what happens to waves when they approach an uneven coastline. As it approaches the shoreline, the wave slows first where the seabed is shallower compared to where it is deeper. This causes the wave to bend, or refract.
What is the top of a wave called?
Crest
What is the bottom of a wave called?
Trough
What is wave length?
Wave length is the distacne between the crest of two waves
What is swash?
When water from waves wash up onto the beach/shoreline
What is backwash?
When water from a wave retreats back into the ocean
What are constuctive waves?
Constructive waves are waves with a strong swash that pulls sediment from the ocean and places it on beaches what in return builds the beach up.
What are destructive waves?
Destructuve waves are waves with a strong backwash and pulls sediment from beaches and bings it into the ocean what in return shrinks our beaches.
Other names for constructive and destructive waves
Erosional - Depotsitional
What are geographical processes?
Actions that cause change to the environment
What is longshroe drift?
The movement of sediment along the shore that is caused by waves
What direction is sand transported along Australias east coast?
North
Why are dunes a crucial?
They protect beaches from major erosion and cause a barrier between the ocean and human built structures, they are also the home of important ecosystems filled with animals and plants.
Why do dunes need vegetation?
The vegetation and its roots hold the dune toghter and stop it from collapsing in on itself. It also provides cover for sand assiting it in not being blown away by wind.
