Cyclones in India: Origin, Impact, and Historical Analysis

Every year, India’s vast coastline faces the fury of nature’s most powerful storms. These swirling masses of wind and rain have shaped the country’s history, claimed countless lives, and continue to test disaster management systems. Understanding cyclones, their origins, and their devastating impact on India is crucial for building resilience in vulnerable coastal communities.

Understanding cyclone formation and characteristics 🔗

The word cyclone carries with it a vivid image. Coined by Henry Piddington in 1840, the term comes from the Greek word “kuklos,” meaning the coils of a snake. Piddington, a British sea captain who later became President of the Marine Courts of Inquiry in Calcutta, chose this name because tropical storms in the Bay of Bengal and Arabian Sea resembled coiled serpents when observed from their circular wind patterns.

Cyclones are large wind systems circulating around centers of low atmospheric pressure. In the Northern Hemisphere, these systems move counterclockwise, while in the Southern Hemisphere, they spiral clockwise. Unlike anticyclones, which are high-pressure systems with outward-spiraling motion, cyclones typically bring heavy rain or snow to affected regions.

India’s vulnerability to cyclonic activity 🔗

The Indian subcontinent stands among the most cyclone-prone regions globally. With an 8,041-kilometer coastline exposed to nearly 10 percent of the world’s tropical cyclones, India faces significant threats, particularly along its eastern coast. Most cyclones originate from the Bay of Bengal before making landfall on India’s east coast.

The North Indian Ocean typically generates five to six tropical cyclones annually, with two to three classified as severe. What makes the Bay of Bengal particularly dangerous is its productivity. For every cyclone forming over the Arabian Sea, four cyclones develop over the Bay of Bengal, establishing an approximately 4:1 ratio.

Why the Bay of Bengal dominates 🔗

Several factors explain this disparity. The Bay of Bengal maintains consistently warm sea surface temperatures above 28 degrees Celsius, often reaching 29-30 degrees Celsius year-round. Being landlocked, it doesn’t receive cold water currents that could lower temperatures. The massive discharge from rivers like the Ganges, Brahmaputra, and Irrawaddy creates lower salinity levels, which facilitate higher evaporation rates and contribute increased moisture to the atmosphere.

The Arabian Sea, meanwhile, experiences cooler sea surface temperatures and higher wind shear, conditions that generally inhibit cyclone formation. However, recent decades have witnessed warming trends, with sea surface temperatures in the Arabian Sea rising by 1.2-1.4 degrees Celsius, contributing to increased cyclonic activity in recent years.

Cyclone frequency analysis across India’s coasts 🔗

Historical data reveals stark differences between India’s eastern and western coasts. Analysis of cyclone frequency between 1891 and 1990 shows that 262 cyclones, including 92 severe ones, occurred within a 50-kilometer strip along India’s east coast. During the same period, the west coast experienced only 33 cyclones, with 19 classified as severe.

The tropical cyclone season in India typically begins in May and June, with a pronounced peak during the post-monsoon period from October to December. Most storms in the Bay of Bengal move in a north-westerly direction, often making landfall in states like Odisha, West Bengal, Andhra Pradesh, and Tamil Nadu.

Historical cyclone casualties that shaped India 🔗

India’s cyclone history is marked by devastating losses that have fundamentally changed how the nation approaches disaster management.

The deadliest historical storms 🔗

The 1737 Hooghly River cyclone remains one of the earliest and deadliest recorded cyclones in Indian history. Striking near Kolkata on October 11, 1737, it generated a massive storm surge estimated at 12 meters high. Historical accounts suggest approximately 300,000 people perished, though modern research estimates the death toll between 25,000 and 45,000. The cyclone devastated Calcutta’s infrastructure, destroying most structures and causing severe flooding across the Ganges River Delta.

The Great Backerganj Cyclone of 1876 struck on October 31, making landfall near the Meghna River estuary in what is now Bangladesh. The storm produced a 12-meter storm surge that drowned tens of thousands instantly. The death toll reached approximately 200,000 to 250,000 people, with many succumbing to subsequent epidemics and famine that followed the flooding.

Modern era catastrophes 🔗

The 1999 Odisha super cyclone marked a turning point in India’s disaster management approach. Making landfall near Paradip on October 29, 1999, with wind speeds reaching 260 kilometers per hour and a record-low pressure of 912 hectopascals, it became the most intense tropical cyclone ever recorded in the North Indian Ocean. Government records indicate 9,885 human casualties, though other estimates suggest the death toll may have reached 30,000. The cyclone damaged 1.6 million homes, affected 12.9 million people, and caused approximately $4.4 billion in damages.

Recent cyclones and improved preparedness 🔗

The landscape has dramatically changed since 1999. Cyclone Fani in 2019 brought wind speeds of 230 kilometers per hour to Odisha, yet resulted in only 64 deaths due to massive evacuations. Cyclone Amphan in May 2020 became the costliest cyclone ever recorded in the North Indian Ocean, causing over $15 billion in damage, but claimed approximately 103 lives in India despite being a super cyclonic storm with wind speeds of 240 kilometers per hour.

Cyclone Tauktae in May 2021 tested Gujarat’s disaster preparedness. As the strongest cyclone to strike the state since 1998, it resulted in at least 169 deaths in India. The cyclone displaced over 200,000 people in Gujarat and demonstrated the increasing frequency of severe cyclones in the Arabian Sea.

Cyclone Phailin in 2013 showcased India’s transformed disaster management capabilities. Despite being among the strongest storms since 1999 with winds of 215 kilometers per hour, fatalities were limited to 46 people after India conducted its biggest evacuation in decades, moving more than half a million people to safety.

The climate change connection 🔗

According to the Union Ministry of Earth and Science, the frequency of very severe cyclonic storms has increased by one per decade over the last two decades, despite an overall decrease in tropical cyclone frequency. During Cyclone Amphan’s rapid intensification, sea surface temperatures reached 33 degrees Celsius in the Bay of Bengal, providing exceptional energy for storm development.

Researchers predict that cyclones will become deadlier and stronger as warming sea surface temperatures continue. Rising sea levels compound the danger, causing higher storm surges and severe flooding in coastal communities.

What do you think? How can India balance rapid coastal development with the increasing threat of more intense cyclones? What lessons from past disasters should guide future urban planning in cyclone-prone regions?

References

1. https://science.thewire.in/society/history/cyclone-nisarga-henry-piddington-cyclonology-port-canning-calcutta/
2. https://ndma.gov.in/Natural-Hazards/Cyclone
3. https://en.wikipedia.org/wiki/North_Indian_Ocean_tropical_cyclone
4. https://www.ipeglobal.com/why-the-bay-of-bengal-is-more-prone-to-cyclones-than-the-arabian-sea/
5. https://www.aashah.com/why-more-cyclones-in-bay-of-bengal-than-in-arabian-sea/
6. https://www.climate.rocksea.org/research/tropical-cyclones-indian-ocean/
7. https://en.wikipedia.org/wiki/1737_Calcutta_cyclone
8. https://www.britannica.com/science/10-Deadliest-Cyclones-in-History
9. https://en.wikipedia.org/wiki/1999_Odisha_cyclone
10. https://www.actionaidindia.org/emergency/odisha-super-cyclone/
11. https://vajiramandravi.com/current-affairs/amphan-cyclone/
12. https://en.wikipedia.org/wiki/Cyclone_Amphan
13. https://en.wikipedia.org/wiki/Cyclone_Tauktae
14. https://www.downtoearth.org.in/natural-disasters/25-years-of-super-cyclone-for-odishas-coastal-villages-the-1999-tragedys-memories-are-still-alive-but-so-is-their-resilient-spirit