Dangers of tropical cyclones

Tropical cyclones are classified by the strength of the wind associated with them, but there are other phenomena which can be just as damaging as the wind that frequently accompany tropical cyclones:

• high seas - large waves of up to 15 metres high are caused by the strong winds and are hazardous to shipping
• storm surge - a surge of water of up to several metres can cause extensive flooding and damage in coastal regions
• heavy rain - the tropical cyclone can pick up two billion tons of moisture per day and release it as rain. This also leads to extensive flooding - often well inland from where the tropical cyclone hit the coast
• tornadoes - tropical cyclones sometimes spawn many tornadoes as they hit land which can cause small areas of extreme wind damage.

These phenomena can cause major destruction, especially when the tropical cyclone's path takes it over land. However, a path over land also causes the destruction of the tropical cyclone itself. As it moves over land, its energy source is depleted and friction across the land surface distorts the air flow. This leads to the eye filling with cloud and the tropical cyclone dies.