What is a Cyclone?

Strong revolving or spiraling storm caused by winds arising from a low atmospheric pressure area is known as a cyclone. Strong whistling and howling winds along with heavy down pour accompany a cyclone. Cyclones in the northern hemispheres blowing in anti-clock wise direction are known as hurricanes or typhoons. The tropical storms blowing in the southern hemisphere are known as cyclones and here the winds blow in a clockwise direction.

Formation of Cyclones

Have you ever wondered how a cyclone occurs? Air near the equator becomes over-heated and rises quickly creating low-pressure areas. As the hot air rises, it becomes laden with moisture. The moisture in the air condenses to produce thunderclouds. When the warm air rises, it creates a vacuum. The cool air gushes in to this void space and later spirals upward with immense force. The reason for spiraling of the air is because of the constant rotation of the earth on its own axis. The wind spirals faster as it moves upwards creating a huge circle that spans up to 2,000 kilometers.

An "eye" of the storm, the central area is very calm and cloudless. The regions that fall under the eye area would not experience rain or high-speed wind.

The upward movement of a cyclone is propagated and sustained by the warm moist air. The thunderclouds form a thick wall 20 to 30 km above the center of the storm. The regions, over which these thunderclouds tower, would experience strong winds and heavy rains. The winds around the eye of the storm would gain momentum of up to 200km/h. Reports and studies reveal around two million tones of air per second gushes out of a fully formed cyclone.

Types of Cyclones

Hurricanes are cyclones that rock the northern hemisphere and strong tropical storms are the cyclones of the southern hemisphere. The formation of both hurricanes and tropical storms are more or less the same.

• Hurricane

Hurricanes are strong spiraling winds blowing at great speeds of 80 to 200 mph. The hurricane cyclones last for at least a week over an ocean. Here they gather momentum to move towards the land. As they reach the land, it results in strong winds and heavy rains which could be harmful for mankind. The hurricane that blows between the months of June and November is known as the Atlantic hurricane. While the hurricane occurring between May and November is called as Eastern Pacific hurricane.

The World Meteorological Organization names the hurricanes. A few of the Atlantic hurricane names are Hanna, Josephine, Fay, Gustav, Alex and so on. Eastern Pacific hurricane names include Barbara, Boris, Agatha, Rachel and many more.

• Tropical Cyclones or Storms

The strong whistling winds that blow in the tropical and subtropical oceans due to low-pressure or depression is known as tropical cyclones. Initially, the tropical cyclones blow at a speed of 63km/h. Once they gather momentum the speed of winds increase to minimum of 118 km/h. Tropical cyclones are a combination of destructive winds and heavy rainfall. A few examples of tropical cyclones include Storm Franklin, Cyclone Adeline Juliet, Nargis and many more.

Cyclones mostly affect the coast regions and global warming could make matters worse. The sea levels would rise because the glaciers melt and this means higher storm surges. Heavy rains will result in flooding. This would lead to damage and destruction to mankind, vegetation and animals living in the coastal areas. Many scientific studies and workshops are carried out to find the connection between global warming and cyclones. The scientists believe the speed of the cyclones have changed dramatically over the last few decades. Hence, the meteorological departments around the globe are having difficulties to establish accurate trends of the cyclones.