Q.Why does tropical cyclone originate over the seas? In which part of the tropical cyclone do torrential rains and high velocity winds blow and why?

Tropical cyclones originate over warm tropical oceans because they require a continuous and abundant supply of warm, moist air. The latent heat released from the condensation of this moisture is the primary energy source that fuels and intensifies the cyclone. Oceans, with surface temperatures typically above 27°C, provide the necessary heat and moisture through evaporation, a condition not met over land. …

Tropical cyclones are powerful weather systems that draw their energy directly from the ocean. Their formation requires very specific conditions, the most fundamental of which is a vast expanse of warm ocean water. Specifically, the sea surface temperature needs to be at least 26.5°C (or 27°C in some contexts) and extend to a depth of at least 50 meters.

This warm water is critical for two main reasons:

• Evaporation and Moisture: Warm ocean water evaporates readily, releasing a tremendous amount of moisture into the atmosphere. This moist air is the primary fuel for the cyclone. As this air rises, it cools, and the water vapor condenses into clouds and rain.
• Latent Heat Release: The process of condensation releases a significant amount of latent heat into the surrounding atmosphere. This heat warms the air, making it less dense and causing it to rise even more vigorously. This creates a positive feedback loop: rising air leads to more condensation, which releases more heat, leading to more rising air, thereby intensifying the storm. Without this continuous supply of latent heat from the warm ocean, a tropical cyclone cannot develop or sustain itself.

Other conditions also play a role in their formation, but they are secondary to the warm ocean requirement:

• Coriolis Effect: A sufficient Coriolis force is needed to initiate the cyclonic rotation. This is why tropical cyclones do not form within about 5 degrees of the equator, where the Coriolis effect is too weak.
• Low Vertical Wind Shear: Wind shear refers to the change in wind speed or direction with altitude. Low wind shear allows the developing storm to maintain its vertical structure and intensify. High wind shear would tear the storm apart.
• Pre-existing Disturbance: A pre-existing weather disturbance, such as a tropical wave, provides the initial low-pressure area around which the cyclone can begin to organize.

The most intense weather, characterized by torrential rains and extremely high-velocity winds, occurs in a specific region of the tropical cyclone known as the eyewall.

The eyewall is a towering ring of intense thunderstorms that surrounds the calm, clear eye of the cyclone. This is where the strongest updrafts of air occur. As warm, moist air spirals inward towards the center of the low-pressure system, it converges and is forced to rise rapidly in the eyewall.

Here's why the eyewall experiences such extreme conditions: …