Tuesday, November 28, 2017

How Cyclones are named ?



One may wonder, what's in a name of a cyclone, but as cyclone heads for a landfall, its name attains almost an iconic status. 

The naming of tropical cyclones is a phenomenon which began officially in 1945 under the aegis of the World Meteorological Organization (WMO). The cyclones were named after women such as Alice, Barbara, Carol, Dolly, Edna, Florence, Gilda, Hazel, Irene, Jill, Katherine, etc.... Subsequent protests by women's liberation bodies in the 60s and 70s helped change the naming procedure for the storms to include male names in 1978. By the beginning of 1980, both men and women's names were used to identify these cyclones. 


Why name cyclones?

Traditionally, cyclones were named by weather bodies, according to latitude-longitude method. But it was difficult to remember and communicate the names in numerical or combination of latitude-longitude data. Thus naming them after a person / flower /animal etc... makes it easier for the media to report on tropical cyclones, helps in quick information exchange between faraway stations, ships etc...., increases disaster risk awareness, community preparedness, management and reduction. It's also easier when you have more than one storm to track.

How are cyclones named?

Initially, a committee of WMO (World meteorological organization) started preparing and maintaining the names of cyclones of Atlantic Ocean. Then WMO divided the world Oceans into Basins and assign the responsibility of naming the Cyclones to the respective regional bodies. Today, there are 5 such regional bodies, called Regional Specialized Meteorological Centers (RSMC)



1. ESCAP/WMO Typhoon Committee : Its members are - Cambodia, China, Democratic People's Republic of Korea, Hong Kong,China, Japan (RSMC Tokyo Typhoon Center) Lao People's Democratic Republic, Malaysia, Philippines, Republic of Korea, Singapore, Thailand, USA (RSMC Honolulu - Hurricane Center), Vietnam .

2. WMO/ESCAP Panel on Tropical Cyclones : Its members are - Bangladesh, India (RSMC-Tropical Cyclones New-Delhi), Maldives, Myanmar, Oman, Pakistan, Sri Lanka, Thailand, Yemen ( added in 2016).

3. RA I Tropical Cyclone Committee for the South-West Indian Ocean : Its members are - Botswana, Comoros, France  (RSMC La Réunion Tropical Cyclone Centre), Kenya, Lesotho, Madagascar, Malawi, Mauritius, Mozambique, Namibia, Seychelles, South Africa, Swaziland, United Republic of Tanzania, Zimbabwe.

4. RA IV Hurricane Committee : Its members are - Antigua & Barbuda, Bahamas, Barbados, Belize, British Caribbean Territories, Canada, Colombia, Costa Rica, Cuba, Curaçao and Sint Maarten, Dominica, Dominican Republic, El Salvador, France, Guatemala, Haiti, Honduras, Jamaica, Mexico, Netherlands, Nicaragua, Panama, St. Lucia, Trinidad and Tobago, UK, USA ( RSMC Miami-Hurricane Center), Venezuela.

5. RA V Tropical Cyclone Committee for the South Pacific and South-East Indian Ocean : Its members are - Australia, Cook Islands, Fiji  (RSMC Nadi - Tropical Cyclone Centre), French Polynesia, Indonesia, Kiribati, Micronesia, New Caledonia, New Zealand, Niue, Papua New Guinea, Samoa, Solomon Islands, Timor Leste, Tonga, Tuvalu, United Kingdom, USA, Vanuatu.

These regional bodies follow their own rules in naming cyclones. Some rotate the same list every 6 years while some don't. Some alternate names between boy and girl, others don’t. But one rule that is common among all five bodies is, if a storm causes extreme widespread damage and deaths, its name is removed from the list so that it cannot be used again at least for 10 years for naming another cyclone. These names are then replaced with new names. The names are removed as a mark of respect to the dead. Eg: Katrina, Mitch and Tracy.

How are cyclones named around Indian Ocean?

For the Indian Ocean region, deliberations for naming cyclones began in 2000 and a formula was agreed upon in 2004. This region consist of eight countries - Bangladesh, India, Maldives, Myanmar, Oman, Pakistan, Sri Lanka and Thailand. Each nation prepares a list of 10 names which they think is suitable to be assigned to a cyclone. They select short names so that people can remember easily. Names are selected which are not associated with any person or religious or any controversial issue. Out of these, the governing body i.e India Meteorological Department (IMD) RSMC Mausam Bhavan in New Delhi, selects 8 names for each country and accordingly prepares and maintains 8 lists which consist of the names approved by the governing body.


From the above naming table, cyclones are re named in chronological order form each list, one after another. According to the list, the first cyclone which occurred in the Indian Ocean in the year 2004 was named Onil. The second cyclone to hit the Indian Ocean was named Agni which was a name submitted by India.

This method is only for North Indian ocean cyclones. In the Australian region they’ve separate system i.e. alternate naming after boy and girl, and so on..