FANI

About: 

• Worldwide terminology: Cyclones are known as –
  • Typhoons in the China Sea and Pacific Ocean;
    
    
  • Hurricanes in the West Indian islands in the Caribbean Sea and Atlantic Ocean;
    
    
  • Tornados in the Guinea lands of West Africa and southern USA.;
    
    
  • Willy-willies in north-western Australia and
    
    
  • Tropical cyclones in the Indian Ocean. 
    
    
  
  
  
• Cause: Cyclones are caused by atmospheric disturbances around a low-pressure area distinguished by swift and often destructive air circulation.
  
  
• Features: Cyclones are usually accompanied by violent storms and bad weather. The air circulates inward in an anticlockwise direction in the Northern hemisphere and clockwise in the Southern hemisphere.
  
  
• Classifications: Cyclones are classified as extra tropical cyclones (also called temperate cyclones); and tropical cyclones.
  
  
• Tropical cyclones:
  • They develop in the regions between the Tropics of Capricorn and Cancer.
    
    
  • The World Meteorological Organisation (WMO, 1976) uses the term 'Tropical Cyclone’ to cover weather systems in which winds exceed ‘Gale Force’ (minimum of 34 knots or 63 kph). 
    
    
  • These are the result of ocean and atmosphere, powered by the heat from the sea; and driven by easterly trades and temperate westerlies, high planetary winds and their own fierce energy.
    
    
  
  
  
• Extra tropical cyclones (temperate cyclones): They occur in temperate zones and high latitude regions, though they are known to originate in the Polar Regions.