How Does the Sea Erode the Coastline? Five Key Processes

1. Hydraulic Action: Wave pressure forces water into cracks, fracturing rock.
2. Abrasion: Sediment-laden waves scour and grind the shore (sandpaper effect).
3. Attrition: Sediment particles collide, breaking into smaller, rounder pieces.
4. Corrosion (Solution): Seawater acids dissolve soluble minerals (limestone, chalk).
5. Bioerosion: Organisms (mussels, urchins, boring sponges) weaken rock by boring.

Erosion rate depends on wave energy, rock type, tidal range, and biological activity. It threatens beaches, infrastructure, and increases flood risk.