cyclone nivar for 14 February 2026

Cyclone Nivar is a severe tropical cyclone which formed in the Bay of Bengal and struck the southeast coast of India in November 2020. 

Cyclone Nivar Naming

The cyclone was named Cyclone Nivar based on the guidelines of the World Meteorological Organisation (WMO). Nivara has been selected from the list of names given by Iran.

• According to WMO guidelines, countries in every region are supposed to give names for cyclones.
• The North Indian Ocean Region covers tropical cyclones formed over Bay of Bengal and Arabian Sea.
• The 13 members, which come under the region, are Bangladesh, India, Maldives, Myanmar, Oman, Pakistan, Sri Lanka, Thailand, Iran, Qatar, Saudi Arabia, the UAE and Yemen.

Cyclone Nivar Impact

Cyclone Nivar struck Puducherry, a district in Tamil Nadu, with a population of 1.6 million people. The cyclone can lead to a huge loss of life and property, especially in low-lying areas. It particularly affected Chennai in Tamil Nadu and Andhra Pradesh further up the coast.  

About Tropical Cyclones

A tropical cyclone is a rapidly rotating storm that begins over tropical oceans, and they can vary in speed, size, and intensity. It is characterized by strong winds, heavy rainfall, thunderstorms, and storm surges

Conditions for Formation

Tropical cyclone formation require following conditions: 

• Warm Sea Surface Temperature: Requires ocean temperatures greater than 27°C. 
• Higher Coriolis Force: Tropical cyclones do not originate between 5°N and 5°S latitudes because the Coriolis force is absent or too weak there.
  • Example:Tropical cyclones do not originate at the equator because the Coriolis force, essential for the rotational deflection of winds, is absent or too weak
• Latent Heat of Condensation: This is the primary source of energy or the "driving engine" for tropical cyclones. They originate only on oceans and seas with abundant moist heat
• Associated with ITCZ: They develop when the Intertropical Convergence Zone (ITCZ) is away from the equator, where there is a convergence of several warm air masses and sufficient heating of water.
• Upper-Air High Pressure / Divergence: There must be an anti- cyclonic condition or high pressure in the upper atmosphere. This divergence in the upper atmosphere allows the air to be continuously thrown upwards, creating a vacuum that pulls in more air and intensifies the low-pressure center. If there's no divergence, cold air would accumulate and descend, preventing cyclone development.
• Absence of Cold Ocean Currents: Tropical cyclones do not originate in regions with cold ocean currents because heat is required. 
  • Example: Tropical cyclones absent on the western coasts of continents like South America, Africa, and Australia.

Structure of a Tropical Cyclone

A tropical cyclone has a well-defined structure. At the center lies the eye, which is a calm and clear area with very low pressure. Surrounding the eye is the eyewall, which contains the most intense winds and heaviest rainfall. Beyond the eyewall are spiral-shaped rainbands that extend outward and produce thunderstorms and heavy showers. The entire system rotates counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere due to the Coriolis effect.

Tropical Cyclones in India

India is highly vulnerable to tropical cyclones because of its long coastline of over 7,500 km. The Bay of Bengal is more prone to severe cyclones compared to the Arabian Sea due to warmer waters and favorable atmospheric conditions. States such as Odisha, West Bengal, Andhra Pradesh, and Tamil Nadu are particularly vulnerable to cyclone impacts. 

Reasons for Higher Frequency in Bay of Bengal

The Bay of Bengal experiences a 35% greater frequency of cyclones compared to the Arabian Sea.

• Warmer Waters: The Bay of Bengal is generally warmer, a key condition for cyclone formation.
• Enclosed Nature: It is more enclosed, being surrounded by land on three sides. This allows the adjacent land to transfer excess heat to the water, contributing to higher temperatures.
• Weaker Vertical Wind Shear: The Bay of Bengal generally has less vertical wind shear (upward and downward motion of wind), which is a favourable condition for tropical cyclones. Cyclones require a consistent upward movement of wind.
• Remnants of Typhoons: The Bay of Bengal's connection to the Pacific Ocean means that remnants of typhoons, after crossing the South China Sea, can enter and intensify in the Bay of Bengal

Tropical Cyclones Regional Names

Tropical cyclones are known by different names in different parts of the world. In the Atlantic Ocean and Eastern Pacific, they are called Hurricanes. In the Western Pacific, they are known as Typhoons. In the Indian Ocean and South Pacific region, they are referred to as Cyclones.