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what are requisite condition for tornado

what are requisite condition for tornado ( extended answer  IFS GK 2011)
 ( answer is extended with related concepts  get your concept  wisely)
Typhoon, Hurricane and Cyclone: Pre-requisites for Formation

A hurricane, a typhoon or a cyclone are all cyclical tropical storms which originate in the oceans, from 10 to 30 degrees away from the equator. The following weather conditions may give rise to a cyclone, hurricane or a typhoon.
  1. A low pressure belt formed over the ocean
  2. A rise in the temperature of the ocean water above 26.5 degrees Celsius
  3. Presence of high velocity winds of at least 119 Km per hour.
When a low pressure belt is formed over the ocean, moist air, replete with water vapors, rises up from the warm ocean waters. These water vapors condense high up in the air, thereby producing a lot of heat. The powerful winds then eat into this heat, thus producing a circular wind system with a warm core. This circular wind system is known as either a typhoon, a hurricane or a cyclone. It is accompanied by torrential rains, thunderstorms, high waves and sometimes even tornadoes

Typhoon, Hurricane and Cyclone : Difference in the Location of Epicenters

The name of the storm system varies according to the place of origin of these storms.

  • Cyclones - Storms are called cyclones if they are formed over the Indian Ocean and Southwestern Pacific Ocean i.e. near Africa and Australia.
  • Typhoon - Storms are called typhoons if they are formed in the Northwestern Pacific Ocean i.e. near Asia.
  • Hurricane - Storms are referred to as hurricanes if formed in Atlantic Ocean and Eastern Pacific Ocean i.e., near Gulf of Mexico and America.
Let's compare typhoon vs cyclone, hurricane vs cyclone and typhoon vs hurricanes, by taking real life examples. Cyclone Nargis in Myanmar in 2008 was called a cyclone, as its location was the northern Indian Ocean. Typhoon Vera which hit Japan in 1959 was called a typhoon, as its location was northwestern Pacific Ocean. Hurricane Katrina which hit USA in 2005 and claimed an estimated 1800 lives is called a hurricane, as its location was the Atlantic ocean.

Typhoon, Hurricane and Cyclone : Difference in Rotational Direction

Even though there is no difference in their speeds, looking at hurricane pictures or the various cyclone pictures available, thanks to the images from a satellite, scientists have discovered that the cyclical direction of the wind varies in different hemispheres. Hurricanes and typhoons which are generated in the northern hemisphere are characterized by the anticlockwise direction of the winds, around the center or the eye of the storm. Hurricanes, typhoons, cyclones which are generated in the southern hemisphere are characterized by the clockwise rotation of the winds around the storm center. For example, a hurricane in USA will always be characterized by counterclockwise direction of the winds as it lies in the northern hemisphere, whereas a cyclone in Australia will produce clockwise winds as it lies in the southern hemisphere.

Hurricanes, cyclones and typhoons can last for a day or stretch to a month. If we compare typhoon, hurricane and cyclone history, we can see that they have been equally responsible for creating destruction and loss in different regions of the world, especially when they reach the populated coastal lands. So, the best way to prevent them is to lower the air and water temperatures worldwide by following environment friendly policies like increasing the green cover and cutting down on greenhouse gas emissions. 


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