How dangerous is Cyclone Vayu

Swirling Destruction - How Does a Cyclone Form?

Cyclone Nargis recently swept over the Southeast Asian country of Myanmar, killing more than 130,000 people and stealing everything they ever owned from another 2.4 million people. How do such tropical cyclones actually arise? We'll explain it to you

The beginning: air on a corkscrew track

Every year cyclones, tropical cyclones, chase over the Indian Ocean with wind speeds of up to 280 kilometers per hour. They especially brew together in the summer months. During this period, the "weather kitchen" of the Indian Ocean simmers. The sun burns vertically on the area around the equator and heats the upper water layer of the ocean to at least 27 degrees Celsius. The consequences: water evaporates, moist, warm air expands and rises like a chimney. This movement creates a low pressure area into which air now flows from all directions.

Where air flows, there are winds. The special thing about this is that these winds do not get straight into the heart of the deep. You will be distracted by the rotation of the earth. This so-called Coriolis force lets the air currents circle around the low. The humid air masses swirl upwards like on a corkscrew track, cool down there and form bands of thick thunderclouds from which it rains, flashes and storms relentlessly.

A dangerous chain reaction

As the storm clouds grow, however, heat is released again. It lets the air parcels that have already risen rise even higher - and air flows in again from below. This chain reaction of ascending, cloud formation, raining down, continuing to climb starts all over again and provides the hurricane with new strength every time. Provided that the incoming air is warm and humid.

Because of this constant self-reinforcement, cyclones can grow to an area of ​​1000 kilometers in diameter - that's further than the distance between Berlin and Paris! On satellite photos, they look like huge eddies that revolve around a cloud-free hole, the so-called eye of the storm.

Cyclone, hurricane or typhoon?

These cyclones are particularly dangerous near the coast, because there they can trigger tidal waves up to ten meters high, which in such densely populated countries as India can make a great many people homeless or even kill them. One of the heaviest cyclones hit the coast of East India in October 1999 with wind speeds of over 260 kilometers per hour. He killed more than 10,000 people and sank over 50 ships in the port of the Indian city of Paradip.

By the way: Tropical cyclones the size of a cyclone also regularly sweep across Northern Australia, America, East and Southeast Asia. But the monsters there are called Willy-Willy (Australia), Hurricane (America) or Typhoon (Southeast Asia).

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