Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R.

Assertion (A): Energy of most cyclones dissipates fast after landfall.
Reasons (R): Surface roughness of land areas is higher than that of oceans.
In the light of the above statements, choose the most appropriate answer from the options given below:

Correct option is A

1. Assertion (A): Energy of most cyclones dissipates fast after landfall:
· True. Cyclones derive their energy from the warm moisture of ocean surfaces. Once they make landfall, their energy supply diminishes due to a lack of moisture and increased friction over land. As a result, the cyclone weakens rapidly.
2. Reason (R): Surface roughness of land areas is higher than that of oceans:
· True. Land has greater surface roughness due to vegetation, buildings, and varying terrain, which increases friction. This friction disrupts the cyclone’s organized wind flow, further reducing its strength.
3. Relationship between A and R:
· The increased surface roughness of land areas causes greater friction, which directly contributes to the dissipation of a cyclone’s energy after landfall. Thus, R is the correct explanation of A.
Information Booster: · Cyclone Formation:
· Cyclones form over warm ocean waters (above 26.5°C), where evaporation and condensation release latent heat, powering the cyclone.
· They have a well-organized structure with a low-pressure center (eye) and spiraling winds.
· Landfall Impact:
· After landfall, cyclones lose access to warm ocean water, their primary energy source.
· Increased friction from land surfaces disrupts wind patterns, accelerating energy dissipation.
· Surface Roughness and Friction:
· Oceans have low surface roughness, allowing smooth wind flow.
· Land, with forests, mountains, and urban infrastructure, exerts higher friction, slowing down winds and weakening the cyclone.