Definition - What does Longshore Current mean?
Longshore Current is an ocean current which moves parallel to the shore. These currents can be found in any beach which is prone to breaking wave. When the large swells sweep into the shoreline at an angle they push the water to the beach in same direction. They are extended to the breaking waves outside from the shallow waters inside. Longshore Currents differ based on their strength, direction and size of an approaching swell and the beach length. A Longshore Current is powerful for the straighter, longer beach with more prominent swell direction and size.
Petropedia explains Longshore Current
Not only do the waves move on the shoreline but also sediments on the shore. As the waves crash against the shoreline, great energy is consumed which makes the water transport the sediments. The resulting transport and the Longshore Currents are the only dynamic processes which alter the shoreline constantly. These currents are responsible for various rescues along the coast as they sweep surfers and swimmers down to the beach. In many of the cases, these currents are strong enough to prevent surfers and swimmers from easily keeping their feet on the bottom which makes it hard for them to return to the shore.