Which type of beach shows summer widening with gentle waves and winter becoming narrow with high-energy waves?

• A. Ocean beach
• B. Lagoons
• C. Barrier flats
• D. Dunes

Answer: (A)

Exposed, open-ocean beaches respond strongly to seasonal wave energy. In summer, the waves are gentler, so sediment tends to be deposited on the beach, building up the berm and spreading the beach landward and widening the profile. In winter, stronger, stormier waves erode that same sediment, remove sand from the upper beach, and steepen the slope, making the beach narrower. This pattern of summer widening and winter narrowing is characteristic of an ocean beach, which lies directly on the open coast without a protective barrier. Lagoons, barrier flats, and dunes involve different dynamics: lagoons and barrier flats are usually sheltered behind barriers with less direct, seasonal wave-driven change, while dunes are shaped more by wind and sand supply than by seasonal wave energy alone.