Structure, features and the development of tropical storms
- From space, a tropical storm looks like a huge whirlpool of spinning clouds.
- Tropical storms are enormous, measuring up to 644 kilometres wide and up to 8 km high. They move quickly in the atmosphere, at up to 60 km/h.
- Tropical storms have circulating winds because of the Coriolis forceApparent force, due to the spinning of the Earth, which deflects movement of particles and wind., caused by the spinning of the planet.
- The area in the middle of a tropical storm is the eye. The eye is up to 48 km across. It is an area of very light wind speeds and no rain, because the air here is descending.
Huge cumulonimbusA type of large, dense, tall, grey cloud which produces rain, hail, or snow. clouds surround the eye, creating the eye wall. Here warm moist air condenseCondensation is a change of state in which gas becomes liquid by cooling. as it rises and this gives the characteristic heavy rainfall and high wind speeds.
How tropical storms develop
Tropical storms usually form between 5掳 and 30掳 latitude.
- When the ocean surface waters reaches at least 27掳C due to solar heating, the warm air above the water rises quickly, causing an area of very low pressure.
- As the air rises quickly more warm moist air is drawn upwards from above the ocean creating strong winds.
- The rising warm air spirals upward and cools. The water vapour it carries condenses and forms cumulonimbus clouds.
- These cumulonimbus clouds form the eye wall of the storm.