UPSC Mains 2013 · GS I · Q19(b) · 5 marks · 100 words

The recent cyclone on east coast of India was called ‘Phailin’. How are the tropical cyclones named across the world? Elaborate.

हिन्दी में

भारत के पूर्वी तट पर हाल ही में आए चक्रवात को ‘फाइलिन’ (Phailin) कहा गया। संसार में उष्णकटिबंधीय चक्रवातों को कैसे नाम दिया जाता है? विस्तार से बताइए।

Cyclones

How a topper answered the closest question

Toppers wrote this one in a test series: “In light of the recently occured cyclone Biparjoy that stuck the Saurashtra and Kutch region of Gujarat, discuss the features and process of formation of tropical cyclone and the change in the nature of cyclones in the Indian ocean.”

Kumud MishraAIR 69 · CSE 2024 · 227 wordsTheir whole copy

Opening · a definition

Tropical cyclones are the low pressure regions with high wind velocity being influenced by the coriolis force of the Earth. Ex. cyclone Amphan, Vayu.

Body · points and prose

The Process of formation of tropical cyclones

→ They are formed in the tropical regions of the Earth with 5 necessary conditions:

  • Sea surface temperature ↑ 27°C
  • Large sea surface area and presence of coriolis force.
  • An already existing weak low pressure area.
  • Minimum variation in vertical wind speed.
  • Upper divergence above the sea level system.

Features of tropical cyclones

↳ cover large sea surface area with high wind velocity. ↳ Develop near low pressure area and frontal system is absent unlike extra tropical cyclones.

Tropical cyclone Eye (calm area)

Diagram
[A vertical cylinder representing the cyclone eye] [Arrows pointing upwards from the center] [Cyclonic flow arrows inside] [Left side: Rain bands, condensation clouds, evaporation (with rain)] [Right side: Rain bands, cumulonimbus clouds, precipitation] [Bottom label: Eye]

↳ they generally develop near tropics moving from East to west in North.

Changing nature in the Indian Ocean

  1. Earlier Bay of Bengal used to experience 6-8 annual cyclones, whereas only 1-2 cyclones in Arabian sea.
  2. But due to global warming, climate change the cyclones in Arabian sea have increased. Ex. Vayu, Nisarga, Tauktae, Biparjoy.
  3. The warming of Arabian sea and the Indian ocean Dipole facilitates cyclones.
  4. The El nino modiki, MJO, Rossby waves with increased moisture have increased the intensity of cyclones.

Close · a way forward

Thus, the need of the hour is to have better Early warning systems in the Indian Ocean region.

How toppers approach this question, and more on its topic: open the question.

Toppers’ answers to other close questions

Source: UPSC, Civil Services (Main) Examination 2013, General Studies Paper I, Q19(b). The paper on upsc.gov.in. Themes and links to toppers’ answers are by UPSC Grade, not by UPSC.