As a geologist with a focus on coastal processes, I can explain the effects of longshore drift. Longshore drift, also known as littoral drift, is the movement of sediments along a coastline in the direction of the prevailing wind-driven current. This process is primarily caused by the interaction between waves and the shoreline.
When waves approach the shore at an angle, they tend to refract, or bend, around the contours of the coastline. This bending causes the wave crests to become more parallel to the shore. As the waves break, the
energy of the waves is directed almost parallel to the beach, pushing sediment along the shore. This movement of sediment is known as longshore drift.
The
consequences of longshore drift are several:
1.
Erosion: Areas where waves are approaching at an angle can experience erosion, as sediments are stripped away from the shore and transported elsewhere.
2.
Accretion: Conversely, areas downdrift (in the direction of the drift) may experience accretion, or a buildup of sediments, as sediments are deposited.
3.
Beach Cusps: The sediment movement can lead to the formation of beach cusps, which are scalloped or circular features in the coastline.
4.
Alteration of Coastal Features: Longshore drift can significantly alter the shape of beaches, spits, and other coastal features over time.
Longshore drift is a natural process that plays a crucial role in shaping and reshaping the world's coastlines.
read more >>