Cyclones - Factfile
What is a Cyclone?
A tropical cyclone is a rotational low pressure system in tropics when the central pressure falls by 5 to 6 hPa from the surrounding and maximum sustained wind speed reaches 34 knots (about 62 kmph). It is a vast violent whirl of 150 to 800 km, spiraling around a centre and progressing along the surface of the sea at a rate of 300 to 500 km a day.
Cyclone Prone Areas in India
Thirteen coastal states and Union Territories (UTs) in the country are affected by tropical cyclones. Four states (Tamil Nadu, Andhra Pradesh, Orissa and West Bengal) and one UT (Puducherry) on the east coast and one state (Gujarat) on the west coast are more vulnerable to cyclone hazards.
The India Meteorological Department (IMD) is the nodal government agency that provides weather services related to cyclones in India.
Classification of Cyclones in India:
The criteria followed by Meteorological Department of India (IMD) to classify the low pressure systems in the Bay of Bengal and in the Arabian Sea as adopted by World Meteorological Organisation (WMO) are as under:
Type of Disturbances
Associated Wind Speed in the Circulation
Low pressure Area
Less than17 knots (<31 kmph)
Depression
17 to 27 knots (31 to 49 kmph)
Deep Depression
28 to 33 knots (50 to 61 kmph)
Cyclonic Storm
34 to 47 knots (62 to 88 kmph)
Severe Cyclonic Storm
48 to 63 knots (89 to 118 kmph)
Very Severe Cyclonic Storm
64 to 119 knots (119 to 221 kmph)
Super Cyclonic Storm
120 knots and above (222 kmph and above)
Recent Cyclones of Andhra Pradesh
Name of the Cyclone
Year of Occurrence
Hudhud
12 October 2014
Lehar
25 November 2013
Helen
21 November 2013
Nilam
October 2012
Laila
May 2010
Khai-Muk
November 2008
Yemyin
June 2007
The recent deadly cyclones that hit Indian coast
Cyclone Phailin (2013) – The Cyclone Phailin is a category 5 storm that struck the Odisha and Andhra coast on 11 October 2013 causing massive destruction in the region- affecting 12 million people. Phailin is a Thai word which means Sapphire. This cyclone prompted India's biggest evacuation in 23 years with more than 5,50,000 people being moved from the coastline in Odisha and Andhra Pradesh to safer shelters. Phailin brought very heavy rain of over 600 mm at many stations of Odisha. It also damaged crops worth Rs 2,400 crore and claimed over 40 lives. Loses due to Cyclone Phailin were estimated to be around rupees 420 crore.
Cyclone Nilam (2012) - Cyclonic Storm Nilam was the deadliest tropical cyclone to directly affect south India that made landfall near Mahabalipuram on October 31 as a strong cyclonic storm with peak winds of 85 kmph. Nilam caused economic losses of around Rs 100 crore because of torrential rain.
Cyclone Thane (2011) - Thane was the strongest tropical cyclone of 2011 that became a very severe cyclonic storm on December 28, as it approached the Indian states of Tamil Nadu and Andhra Pradesh and made landfall at north Tamil Nadu coast between Cuddalore and Puducherry on December 30. Thane left at least 46 people dead in Tamil Nadu and Puducherry. Cuddalore and Puducherry were the worst affected areas.
Cyclone Laila (2010) - Severe cyclonic storm Laila made a landfall in Andhra Pradesh on the 20 May 2010 and caused major flooding and damage along its path. Ongole in Andhra Pradesh recorded heavy rainfall of about 460 mm in just two days. Another town Addanki received the highest rainfall of 522 mm. The state government faced a loss of over Rs 500 crore due to Cyclone Laila.
Cyclone Jal (2010) - Cyclone Jal killed at least 54 people in India alone. About 300 thousand hectares of cropland was devastated by the cyclone. The remnants of Jal continued to move northwest, brought light to moderate spells of rain in India's warmest state of Rajasthan and also in Gujarat.
Cyclone Phyan (2009) - Cyclonic Storm Phyan developed as a tropical disturbance in the Arabian Sea to the southwest of Colombo in Sri Lanka on November 4, 2009 and made landfall in south India on November 7. Massive damage to property was reported in coastal districts of Maharashtra, such as Ratnagiri, Raigad, Sindhudurg, Thane and Palghar.
Cyclone Nisha (2008) - Over 180 people were killed in Tamil Nadu alone due to heavy rain and floods caused by the cyclone. Orathanadu, in Thanjavur District in Tamil Nadu received over 990 mm of rain within 24 hours. The total amount of rainfall received from Nisha was about 1280 mm. The damage caused by the cyclone was estimated to be about 3789 crores.
The 30 Deadliest Tropical Cyclones in World History
Rank
Name / Areas of Largest Loss
Year
Ocean Area
Deaths
1.
Great Bhola Cyclone, Bangladesh
1970
Bay of Bengal
500,000
2.
Hooghly River Cyclone, India and Bangladesh
1737
Bay of Bengal
300,000
3.
Haiphong Typhoon, Vietnam
1881
West Pacific
300,000
3.
Coringa, India
1839
Bay of Bengal
300,000
5.
Backerganj Cyclone, Bangladesh
1584
Bay of Bengal
200,000
6.
Great Backerganj Cyclone, Bangladesh
1876
Bay of Bengal
200,000
7.
Chittagong, Bangladesh
1897
Bay of Bengal
175,000
8.
Super Typhoon Nina, China
1975
West Pacific
171,000
9.
Cyclone 02B, Bangladesh
1991
Bay of Bengal
140,000
9.
Cyclone Nargis, Myanmar
2008
Bay of Bengal
140,000
11.
Great Bombay Cyclone, India
1882
Arabian Sea
100,000
12.
Hakata Bay Typhoon, Japan
1281
West Pacific
65,000
13.
Calcutta, India
1864
Bay of Bengal
60,000
14.
Swatlow, China
1922
West Pacific
60,000
15.
Barisal, Bangladesh
1822
Bay of Bengal
50,000
15.
Sunderbans coast, Bangladesh
1699
Bay of Bengal
50,000
15.
India
1833
Bay of Bengal
50,000
15.
India
1854
Bay of Bengal
50,000
19.
Bengal Cyclone, Calcutta, India
1942
Bay of Bengal
40,000
19.
Bangladesh
1912
Bay of Bengal
40,000
19.
Bangladesh
1919
Bay of Bengal
40,000
22.
Canton, China
1862
West Pacific
37,000
23.
Backerganj (Barisal), Bangladesh
1767
Bay of Bengal
30,000
24.
Barisal, Bangladesh
1831
Bay of Bengal
22,000
25.
Great Hurricane, Lesser Antilles Islands
1780
Atlantic
22,000
26.
Devi Taluk, SE India
1977
Bay of Bengal
20,000
26.
Great Coringa Cyclone, India
1789
Bay of Bengal
20,000
28.
Bangladesh
1965 (11 May)
Bay of Bengal
19,279
29.
Nagasaki Typhoon, Japan
1828
Western Pacific
15,000
30.
Bangladesh
1965 (31 May)
Bay of Bengal
12,000