AIM: How do waves shape the Shoreline? Do Now: In your notes answer the following question. Think about the times you were at the beach. Maybe you built a sand castle near the shore line. What would the waves do to your castle?

I. Wave Formation Waves are created by the transfer of energy from the atmosphere to the hydrosphere (wind creates waves). Storms increase the activity of waves.

II. Wave Erosion Longshore current: flows parallel to the beach and moves fine-grained sediments (sand and silt). - Larger sediments (pebbles) are rolled along the bottom by the current.

Sediment moving in the water causes abrasion to occur forming Sea Arches and Sea Stacks

What would help these sand bars become more permanent? III. Wave Deposition - The accumulation of sediment along the shore is called a beach. A. Sand bars: shifting mounds of sand in the ocean near the shore. (not permanent) B. Barrier Islands (beaches): Permanent larger sand bars that create bays. - Long beach and Fire Island What would help these sand bars become more permanent?

What does the deposited sand tell us about the wave direction? IV. Beach Preservation - Groins, Jetties, sea walls and breakwaters all protect a coast from erosion by stopping the wave and making sediment deposit. What does the deposited sand tell us about the wave direction? Wave direction Deposition The side of the jetty with deposited sand is where the wave is coming from.

What direction is the wave coming from? Wave path N

N Where are the waves coming from? W E S

Closure: Obtain a worksheet on Waves from the bottom do now bin. With the person sitting next to you use the notes to answer the questions on the handout.

N W E S

1. Where is the longshore wave coming from? 2. Jetties keep sand from being eroded away from the beach. They catch the sand and force the wave to deposit it nea2 the jetties.

3. Wave erosion creates sea arches and sea mounts because of differential weathering by the waves. Wave deposition creates sand bars and barrier islands due to deposition of the sand.

Process Differences Similarities Glacier Wind Wave