Calcutta Cyclone of 1737
Calcutta, or Kolkata as of 2001, is located on the Southeastern coast of India, (as seen on Fig. 1.) Kolkata is the largest metropolitan city in India, with a modern population of about 13.5 million people. Calcutta is a city by the sea, and also resides at a fairly low spot by the coast, (as seen on Fig. 1,) which leaves it wide open to many hazards.



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(Figure 1: You can see Kolkata’s' relationship to the ocean, and where it stands as far as height above sea level. You can see it is fairly low on the scale, making it septable to oceanic storms, or tsunami waves. "Topography of India." Google.com)


The hazard we will be focusing on is the Cyclone, or Typhoon, of 1737. On 7 October 1737, it is said 300,000 people and 20,000 boats were taken by huge waves thought to be caused by an Earthquake Tsunami. But through numerous accounts taken over time after the event, a second cause came to be realized. As you can see on Fig. 2, the nearest convergent plate boundary is on the Northern boarder of the country, also known as the Himalayas. The nearest boundaries off the coast are transform, or divergent boundaries which can not cause massive Tsunamis, as thought to be the cause of all the damage. The towns and villages of that time were poorly constructed, which during the disaster crumbled and broke down adding to the death toll. There is confusion if the earthquakes caused the houses to collapse and then the water came into play, or if it was the massive floods of ocean water that caused it all. There was claimed to be waves 40 feet high, caused by the earthquake surged on land wiping out the homes at night, and sweeping the offshore ships on land. Some also that claim that while the typhoon tore through the city, an earthquake struck causing the final blow to the already weakened houses. Other inhabitants claim there was no earthquake, but just a massive storm that struck the densely populated area and the feelings of earthquakes were that of the houses and buildings failing (Bilham Roger.)

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(Figure 2 as you can see on the map of the plate boundary, there is no plate boundary in that area that can send a tsunami surging into India. The closest convergent boundary is actually inland which created India’s Himalayan Mountains, and the only offshore boundary is a divergent boundary. Tectonic Plate Boundaries." Yahoo Images)

There is a big problem found about the death tolls recorded for this disaster. It is claimed that 300,000 people died in this cyclone, but around the same time, it was recorded that the population was 20,000. The differences came from the city of Calcutta and the Merchant Ship reports of that time (Bilham Roger). There are so many various accounts, and it happened such a long time ago that it is hard to determine what really happened. Facts that certain are that the disaster was major incident that took a lot of lives and leveled a lot of land.


Since accurate records are hard to record for a disaster that happened so long ago, common sense and current knowledge has to some into play which is why the over all census of this disaster has changed in the past years. This area is well known to receive massive cyclones and as you can see in figure 3, a storm surge is the best probability of water damage on land during that time. Some records also state that this 1737 cyclone could have been one of the worst cyclones to have ever hit India (Emergency Disasters Inc., 2008)

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(Figure 3: as the eye pulls in air at extreme speeds the water underneath the eye will also raise up to a few meters, this is known as a storm surge and can cause massive damage, being equivalent almost to a small tsunami. ("Fully formed tropical cyclone"))

There were reports in Roger Bilhams article that said there was also damage to surrounding states along the coast which would be another great indication that a tropical cyclone could have curved along the coast hitting any city in its path. Also with that time era, building we not made to hold up to strong winds and massive water movements across land which all contributed to the loss in many lives. The discrepancy in lives lost comes from the age of the disaster, happening hundreds of years ago, no real accounts taken. Our facts come from accounts taken from the few people who survived and stories told throughout the years, and also what knew knowledge modern science can bring into the picture. All the new evidence can do is make known that the disaster was more along the lines of a storm rather than a tsunami. There could have very well been an earthquake that night or the storm, that sent waves thought India, but the demolition of the city and the death toll can be accounted for a massive storm that wiped the land clean.


Works Cited
Bilham, Roger. "The 1737 Calcutta Earthquake and Cyclone evaluated." Bull. Seism. Soc. Am. Vol 84 (Oct 1984): 1-10. Print.

"History of Kolkata - Historical Information of Kolkata - About Kolkata - My CityPedia." Kolkata India - Kolkata Information Guide - News, Events, Classifieds, Shopping, Education, Travel, Hotels, Business - Click India. Web. 17 Feb. 2010. <http://kolkata.clickindia.com/general/history.html>.

"Pre-1980 North Indian Ocean cyclone seasons." Answers.com. Web. 17 Feb. 2010. <http://www.answers.com/topic/pre-1980-north-indian-ocean-cyclone-seasons#1737_Calcutta_Cyclone>.

Tectonic Plate Boundaries." Yahoo Images. Edvantage Press. Web. 17 Feb. 2010. http://www.regentsearthscience.com/tsunami/plates.gif>.

"Topography of India." Google.com. Web. 17 Feb. 2010. http://images.google.com/imgres?imgurl=http:www.travelindia-guide.com/maps/india/topography.jpg&imgrefurl


"Fully formed tropical cyclone." tropical cyclones//. Web. 3 Mar 2010. <http://images.search.yahoo.com/images/view?back=http%3A%2F%2Fimages.search.yahoo.com%2Fsearch%2Fimages%3Fp%3Dtropical%2Bcyclones%26sado%3D1%26ei%3Dutf-8%26fr%3Dmcafee%26fr2%3Dsg-gac&w=550&h=293&imgurl=www.aerospaceweb.org

Emergency Disasters Inc., EDM. (2008). Cyclones. Retrieved from http://www.emergency-management.net/cyclone.htm