Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
Transcript of Shoreline Webquest
Longshore currents are an ocean current that moves parellel to the shore.
Size, strength and direction affect longshore currents.
Longshore currents are dangerous because it can carry swimmers and surfers into rip currents, piers, and other hazardous areas.
Longshore currents affect beaches because the waves aren't parrallel to the shore so they hit the shore at an angle.
Barrier Islands are islands that are parallel to the coast. They are formed by clumps of sand eroded from the ocean floor. Barrier islands protect the coast by taking some of the damage and eroded sand from heavy storms over the ocean. They can change if a particular storms flood the island and cover it. Also, large waves can slowly erode the island or cover it.
A seawall is a form of coastal defense.
The purpose of a seawall is to protect areas of human habitation, conservation, and leisure activities.
Advantages- Longterm solution, minimizes loss of life,
Disadvantages- Very expensive,beaches dissipate, and reflected waves heading to scour at base.
The three types of Seawalls are Vertical, Curved, and Mound.
Beach nourishment is the process of dumping or pumping sand from elsewhere onto an eroding shoreline to create a beach r to widen an existing beach.
Beach nourishment does not completely stop erosion.
An advantage of beach nourishment is that structures behind the beach are protected as long as sand remains.
A disadvantage of beach nourishment is that it is expensive and has to be repeated periodically.
A groin is a low or sturdy timber barrier built in the sea to check erosion.
They are designed to check erosion and drifting.
A problem with them would be the fact that they cause too much sediment.
A jetty is a breakwater constructed to protect and defend a harbor.
the jetty acts as a arrier against erosion from currents, tides, and waves.
A problem with jetties is that they permanently disrupt the equilibrium of the beach.
Groins and jetties are different because jetties are larger and create larger updrift beaches.
Jetties are maintained by sand pumping which is very expensive.