Science Unit 5 Lesson 1 Flashcards
What is beach erosin?
Beach erosion is when sand is removed from the beach and deposited in deeper waters offshore.
What are the 3 main causes of beach erosin?
- Human activity
- Ocean currents
- Storm waves
How does the movement of waves and ocean currents remove sand from the beach?
As waves crash against the shore, the current removes and carries the sand out to deeper waters.
How do storms contribute to beach erosin?
When a storm occurs, the waves grow bigger and stronger. These storm waves deposit a lot of sand in large, offshore sandbars
How long can it take the sand from sandbars to come back on the beach?
It can take weeks and even months before this sand returns to the beach.
What does ocean current mean?
continuous movement of seawater
How can human activity accelerate beach erosion?
Human activity can cause and sometimes accelerate erosion. Building close to the coast can have an effect on beaches and speed up erosion.
What can happen to sand dunes during building?
They can be damaged
Why are sand dunes important?
Sand dunes, which separate low-lying beaches from higher grounds, can be damaged during the building process. These dunes help to prevent water from going too far inland. If the dunes are damaged, water is able to flow inland, causing shorelines to change.
Because of erosin beaches have become what?
Because of erosion, beaches have become narrower and the elevation lower. Less sand simply means less beach
As erosion continues, what happens to the shorelines?
They begin to shift or move inland
What is a shoreline?
where a body of water meets the land
What is causing erosion of Miami Beach?
one-third of the
sand on Miami Beach was lost due to huge storm
waves produced by Hurricane Irma
