36. Mains Question- Oct 04, 2018
Explain the formation of a tropical cyclone. (250 words)
- Theme of the question: Formation of a tropical cyclone
- Give a brief introduction of what tropical cyclones are. For example: a localized, very intense low-pressure wind system, forming over tropical oceans and with winds of generally high speeds
- Give a step by step elucidation on the formation of these systems. Such as:
- They form only over warm ocean waters near the equator.
- The warm, moist air over the ocean rises upward from near the surface. Because this air moves up and away from the surface, there is less air left near the surface, causing an area of lower air pressure below.
- Air from surrounding areas with higher air pressure pushes in to the low pressure area. Then that “new” air becomes warm and moist and rises, too.
- As the warm air continues to rise, the surrounding air swirls in to take its place. As the warmed, moist air rises and cools off, the water in the air forms clouds. The whole system of clouds and wind spins and grows, fed by the ocean’s heat and water evaporating from the surface.
- Storms that form north of the equator spin counterclockwise. Storms south of the equator spin clockwise. This difference is because of Earth’s rotation on its axis.
- As the storm system rotates faster and faster, an eye forms in the center. It is very calm and clear in the eye, with very low air pressure. Higher pressure air from above flows down into the eye.
- Tropical cyclones usually weaken when they hit land, because they are no longer being “fed” by the energy from the warm ocean waters
- Extended reading: Kindly analyze the pattern of tropical cyclone pattern in Indian Ocean. The role of agencies in disasters caused due to cyclones both at the central and state level