HOW DANGEROUS ARE WHIRLPOOLS?
Whirlpools occur when two opposing currents meet. They cause the water to spin round very rapidly. Huge whirlpools at sea are normally caused by powerful tides.
The most famous whirlpool in the Maelstrom, which appears between two islands off the coast of Norway. Sometimes this whirlpool is even strong enough small ships.
The ancient Greeks believed that the Charybdis whirlpool in the Mediterranean was caused by a monster.
WHAT CAUSES WAVES IN THE SEA?
Have you noticed that on a calm day there are very few waves and on a windy or stormy day there are many waves? This is because it is a combination of the wind the shape of the seabed that causes waves.
The wind blows the surface layers of the sea, gradually forming a rolling movement of waves. A wave is in fact an up-and-down movement of water particles. As the bottom of a wave strikes the ground at a short distance from the beach, it slows up because of the friction. The top keeps going, and then topples over, and this is what forms a ‘breaker’.