Cyclone and its formation
What is cyclone :
- A cycloneis basically a large air mass that rotates around a strong center of low atmospheric pressure.
- It rotates in counter clockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.
- The process of cyclone formation and intensification is known as
Types of cyclones :
- There are basically two types of cyclones.
- Tropical cyclones which occur in tropical areas around the world.
- Temperate cyclones also known as extra tropical cyclones or wave cyclones occur due to fronts.
Temperate cyclones around the world
Tropical cyclones :
- Tropical Cyclones are one of the most devastating natural calamities around the world.
- These are violent storms which originate over the seas and oceans in tropical areas.
- After originating they move over to the coastal areas bringing about large scale destruction.
- The destruction is due to violent winds, very heavy rainfall.
- They mostly originate and intensify over warm tropical oceans which acts as heat engine.
- The conditions favourable for the formation and intensification of tropical storms are:
- Large sea surface with temperature higher than 27° C.
- Presence of the Coriolis force.
- Small variations in the vertical wind speed.
- A pre-existing weak low- pressure area
- Upper divergence above the sea level system.
Structure of the Tropical Cyclone :
- The main parts of a tropical cyclone are the rainbands, the eye, and the
- Air spirals in toward the center in a counter-clockwise pattern in the northern hemisphere (clockwise in the southern hemisphere), and out the top in the opposite direction.
Coastal areas vulnerable to cyclones in India :
Classification of Cyclones according to the wind speed :
Syllabus : Prelims + Mains; GS1 – Geography