Destructive waves are formed when the backwash (water flowing back down the beach) is stronger than the swash (water washing up the beach). This leads to erosion, carrying sediment away from the beach and resulting in a steeper beach profile.
Here's a more detailed breakdown:
- Dominant Backwash: The key characteristic of destructive waves is a stronger backwash than swash. This means the receding water has more energy.
- Erosion: The powerful backwash erodes the beach, pulling sand and other material out to sea.
- Steep Beach Profile: Over time, the continuous erosion causes the beach to become steeper.
- Wave Characteristics: Destructive waves typically have the following characteristics:
- Steep Profile: They have a steeper, more peaked shape.
- Large and High Crests: Destructive waves are often larger and have higher crests compared to constructive waves.
- High Frequency: They arrive more frequently, meaning there's less time between waves.
In essence, destructive waves are powerful erosional forces that reshape coastlines by transporting sediment offshore.
