Shaping Coastlines

This set of vocabulary flashcards covers concepts related to coastal formation, causes of erosion, wave characteristics, and seasonal beach profiles.

Coastlines

Compositions of mud, sand, coral, and rock shaped by the action of wind, waves, and water.

Coastal erosion

The permanent loss of land along the shoreline.

Natural Causes of Coastal Erosion

Changes in wave climate (height, angle, or frequency), reduction in reef sediment delivered to the coast, and rising sea level.

Human Induced Causes of Coastal Erosion

Sand extraction, coral mining, removal of mangroves, and the insertion of structures like seawalls that alter wave processes.

Contributing factors to beach erosion

Coastal Development (loss of dune protection), Climate Change (storms and sea level rise), and the removal of dune vegetation.

Crest

The top of the wave.

Trough

The valley between two crests.

Wave height

The vertical distance between the crest and the trough.

Wave length

The distance between two successive crests or troughs.

Wave period

The time taken for two successive crests or troughs to pass a fixed point.

Wave transformation (near shore)

As waves approach the shore, they become steeper, lose their shape and topple, and release energy to form surf.

Wavelength and Depth relationship

Wavelength decreases as water depth decreases.

Sand banks

Areas where waves break and rush towards the beach, causing a constant movement of sand in this area.

Summer beach profile

A wider beach with more sand caused by smaller waves gradually moving sand inward from sandbanks.

Winter beach profile

A narrow beach with less sand caused by winter storms that build up waves and wipe out the beach.

Cyclone season impact

High winds make waves larger, creating harsh breaking waves with strong backwash that moves sand from the beach out to sea.

Offshore storm bar

A feature formed from eroded sand moved offshore by large waves during a storm; results in a narrower beach.

Erosion scarp

A feature that forms on an eroding beach during a storm as large waves attack the shoreline.

Accreting beach

A beach where smaller waves move sand off the storm bar back towards the beach to re-establish the profile.