Hurricane Nana | 04 Sep 2020

Why in News

Atlantic Hurricane Nana has made a landfall on the coast of Belize.

• The country Belize is located on the northeast coast of Central America.
• Few days back, Hurricane Laura made landfall in southwestern Louisiana (South Central United States).

Key Points

• Tropical Cyclone:
  
  • A hurricane is a type of storm called a tropical cyclone, which forms over tropical or subtropical waters.
  • A tropical cyclone is a rotating low-pressure weather system that has organized thunderstorms but no fronts (a boundary separating two air masses of different densities).
• Speed of Winds:
  
  • Tropical cyclones with maximum sustained surface winds of less than 39 miles per hour (mph) are called tropical depressions.
  • Those with maximum sustained winds of 39 mph or higher are called tropical storms.
  • When a storm's maximum sustained winds reach 74 mph, it is called a hurricane.
• Measurement of Wind Speed:
  
  • The Saffir-Simpson Hurricane Wind Scale is a 1 to 5 rating, or category, based on a hurricane's maximum sustained winds.
  • The higher the category, the greater the hurricane's potential for property damage.
• Formation:
  • There needs to be warm ocean water and moist, humid air in the region.
  • When humid air is flowing upward at a zone of low pressure over warm ocean water, the water is released from the air as creating the clouds of the storm.
• Features:
  
  • It has a low pressure centre and clouds spiraling towards the eyewall surrounding the "eye", the central part of the system where the weather is normally calm and free of clouds.
  • Its diameter is typically around 200 to 500 km, but can reach 1000 km.
  • The winds blow counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.
  • A tropical cyclone brings very violent winds, torrential rain, high waves and, in some cases, very destructive storm surges and coastal flooding.
• Different Names:
  
  • Hurricane: Caribbean Sea, Gulf of Mexico, North Atlantic Ocean and the eastern and central North Pacific Ocean
  • Typhoon: Western North Pacific
  • Cyclone: Bay of Bengal and Arabian Sea
  • Willy-willies: Australia

Source: IE