Tropical cyclones are intense low-pressure systems forming over warm tropical oceans, driven by latent heat of condensation. They are known for spiraling winds, torrential rains, and storm surges, affecting millions in India’s 7,500-km-long coastline every year.
Formation of Tropical Cyclones:
Favourable Conditions:
- Sea surface temperature above 27°C up to 60–70 m depth.
- Coriolis force (5°–20° latitudes) to initiate cyclonic rotation.
- High humidity in the mid-troposphere.
- Low vertical wind shear for organized convection.
- Pre-existing low-pressure disturbance in the ITCZ.
- Upper-level divergence to sustain the upward motion.
Stages of Development:
- Origin: Local thunderstorms merge into a low-pressure area.
- Intensification: Warm, moist air rises; condensation releases latent heat, reducing pressure further.
- Cyclonic Vortex Formation: Coriolis force induces spiraling motion leading to vortex formation.
- Eye Formation: Calm zone forms at the center, surrounded by the violent eyewall.
- Mature Stage: Maximum wind and rainfall intensity during landfall.
- Dissipation: Weakening post-landfall as the moisture source is cut off.
Impacts of Tropical Cyclones on India:
(i) Cyclone Amphan (2020):
- Landfall: West Bengal coast near Sunderbans; winds up to 240 km/h.
- Coastal Flooding & Erosion: Storm surges of 4–5 m submerged low-lying deltaic areas, eroding mangrove belts in the Sunderbans.
- Infrastructure Loss: Over 5 lakh houses destroyed, electricity grid collapsed in Kolkata leading to damages worth ₹1.02 lakh crore.
- Ecological Impact: Salinization of paddy fields and up to 28% mangrove degradation being recorded by NRSC.
- Livelihood Disruption: Affected 13 million people, displacing over 2 million, mainly farmers and fisherfolk.
(ii) Cyclone Montha (2025)
- Landfall: Between Machilipatnam and Kalingapatnam (Andhra Pradesh).
- Agricultural Impact: Heavy rainfall (210 mm/24 hrs) damaged standing crops such as paddy and pulses across Krishna and Guntur districts with an estimated ₹2,400 crore crop loss.
- Livelihood Impact: Over 1.5 lakh fisherfolk stranded due to port closure. Daily wage labourers and salt-pan workers lost income for weeks.
- Infrastructure: Uprooted trees and disrupted power supply in coastal villages as over 300 km of rural roads damaged.
Conclusion:
Cyclones, though natural climatic phenomena, are becoming more frequent and intense due to climate change and rising sea surface temperatures. India’s focus should be on climate-resilient coastal infrastructure, mangrove restoration, and community-based disaster preparedness to reduce vulnerability.
‘+1’ Value Addition
- As per IMD, Early-warning dissemination now covers 95% of coastal population, reducing fatalities by 90% since 1999.
- As per World Bank, India loses about $2–3 billion annually due to cyclone damages.
- NDMA’s NCRMP strengthened multi-hazard shelters and embankments across 13 coastal states.
La Excellence IAS Academy, the best IAS coaching in Hyderabad, known for delivering quality content and conceptual clarity for UPSC 2025 preparation.
FOLLOW US ON:
â—‰ YouTube : https://www.youtube.com/@CivilsPrepTeam
â—‰ Facebook: https://www.facebook.com/LaExcellenceIAS
â—‰ Instagram: https://www.instagram.com/laexcellenceiasacademy/
GET IN TOUCH:
Contact us at info@laex.in, https://laex.in/contact-us/
or Call us @ +91 9052 29 2929, +91 9052 99 2929, +91 9154 24 2140
OUR BRANCHES:
Head Office: H No: 1-10-225A, Beside AEVA Fertility Center, Ashok Nagar Extension, VV Giri Nagar, Ashok Nagar, Hyderabad, 500020
Madhapur: Flat no: 301, survey no 58-60, Guttala begumpet Madhapur metro pillar: 1524, Rangareddy Hyderabad, Telangana 500081
Bangalore: Plot No: 99, 2nd floor, 80 Feet Road, Beside Poorvika Mobiles, Chandra Layout, Attiguppe, Near Vijaya Nagara, Bengaluru, 560040