Cyclones generally occur in 3 stages : Tropical
Cyclones, severe Cyclones and Super cyclones. When the storm in a Cyclone blows at a speed
of less than 74 miles/hour, it is called a Tropical Cyclone. When it gets intense and the speed is between
75 to 120 miles/Hour, then it becomes a Cyclone or a Severe Cyclone. When the Speed increases for more than 120
miles per hour. It becomes a Super Cyclone. How are these cyclones formed? Where are they initiated? Hurricanes, Typhoons, what are they? Let’s see. By the way, Don’t forget to subscribe to
DNA, so that you don’t miss out any of the new videos that we post. Cyclone is a general term used by meteorologists
to describe any rotating, organized cloud that originate over waters. Cyclones, Hurricanes, Typhoons. One Event but different names depending on
the location. In Atlantic and Northeast Pacific it is called
“Hurricane” . In Northwest Pacific, it is termed as “Typhoon” and in the South
Pacific and Indian Ocean it is called a “Cyclone”. You can also, classify them with hemispheres,
the Northern ones as Hurricanes and Southern ones as Cyclones. There are also a few other differences in
them apart from where they originate, like the cyclones are usually Clockwise and Hurricanes
are Counterclockwise. Where do these Cyclones Originate? When the Atmospheric pressure is low over
a large waterbody, that is still and the temperature of the water is more than 26.5*C, then they
form into a cyclone. What is atmospheric pressure in general terms? The density of Air in our atmosphere differs
from place to place, They are not same everywhere. Atmospheric pressure is the weight of Air
acting against the surface of the Earth, along with Gravity. Air in the atmosphere creates a pressure on
Earth’s Surface called Atmospheric pressure. Atmospheric pressure is more on the earth
surface and as we move upwards, there is less amount of air and hence atmospheric pressure
decreases. When there is low Atmospheric pressure on
a Large water body on earth surface, they turn into a cyclone. This process of thin air circulating, strengthening
and developing into Cyclonic formation is called Cyclogenesis. So how does it become a huge stormy, cloudy
Cyclone? When the atmospheric pressure is low, the
warm air rises to fill the gaps and cold air goes down, as they have moisture in it. The warm air as it reaches the place, it becomes
more warm and it rises rapidly Thus creating more Gap. So the surrounding air rushes in, to fill
the place. These filling air travels at greater speed
and from longer distance. When they reach the area, instead of filling
the gaps, they start circulating thus creating a spiral. After that any air travelling to fill the
gap has to join the spiral. Because Air cannot pass through spiral directly. Usually Tropical Cyclones range from 100kms
to 2000kms in diameter. When a large amount of air is rushing to fill
the gap, they form huge Cyclones and the spiral structure is becomes larger and larger penetrating
the clouds and thus creating Thunderstorms. Tropical Cyclones can grow up to a height
of 10kms and they last from 3 – 7 days, depending on the speed of the storm, how far
it is from the land, and how big it is. Cyclones usually fade away or die, when they
cross the land area. There is a misconception that the buildings
and other interruptions on the land surface act as a barrier and stop the cyclone. But that’s not it. When the Cyclonic Storm crosses the land surface,
the main source of the cyclone, that is the “warm water” is taken away. Cyclones work with Moist warm Air. So when it crosses a cold water surface or
a land surface, they die. Since 957 A.D, for almost 1000 years now,
there has been at least 11,982 recorded Tropical Cyclones in the Atlantic, Pacific and Indian
Ocean. And So far the largest ever recorded is the
“Typhoon Tip” that occurred in 1979 in the South Pacific ocean near Philippines,
which was 2200 km in Diameter with a wind speed of 190 miles per hour, that is 305km/hr. It lasted for almost 20 days. This is said to be the largest and strongest
Cyclone ever recorded in history. For More Information videos on Science, Technology,
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