Six lists are used in rotation. Thus, the list will be used again in The only time that there is a change in the list is if a storm is so deadly or costly that the future use of its name on a different storm would be inappropriate for reasons of sensitivity. If that occurs, then at an annual meeting by the WMO Tropical Cyclone Committees called primarily to discuss many other issues the offending name is stricken from the list and another name is selected to replace it.
There are five tropical cyclone regional bodies, i. For instance, Hurricane Committee determines a pre-designated list of hurricane names for six years separately at its annual session. Naming procedures in other regions are almost the same as in the Caribbean. In some of the regions, the lists are established by alphabetical order of the names. In other regions, the lists are established following the alphabetical order of the country names - please see "Tropical Cyclone Names Worldwide" below for more details.
In general, tropical cyclones are named according to the rules at a regional level. The names selected are those that are familiar to the people in each region.
The list of hurricane names covers only 21 letters of the alphabet as it is difficult to find six suitable names one for each of the 6 rotating lists starting with Q, U, X, Y and Z.
In the interests of safety, the name must be instantly recognizable. In addition, English, French and Spanish names are used in balance on the list in order to reflect the geographical coverage of Atlantic and Caribbean storms. The list is also gender balanced and respectful of societal sensitivities. Until , when a very active hurricane season occurred and the list was exhausted, the Greek alphabet was used Alpha, Beta, Gamma, Delta, Epsilon, Zeta, Eta, Theta, etc. This has occurred twice.
The first time was in - a record-breaking year with several devastating hurricanes including Katrina, Rita and Wilma, whose names were all retired - when six names from the Greek alphabet were used. The second was in - a new-record breaking year with 30 named tropical storms of which nine names from the Greek alphabet, including the devastating hurricanes Eta and Iota.
Starting , in lieu of the Greek alphabet, the lists of supplemental tropical cyclones names will be used. A name can be retired or withdrawn from the active list at the request of any Member State if a tropical cyclone by that name acquires special notoriety because of the human casualties and damage incurred.
The decision to withdraw or retire a name is reached by consensus or majority vote during the WMO Regional Association IV Hurricane Committee session that immediately follows the season in question. The WMO Regional Association IV Hurricane Committee annual session in discussed the use of the Greek alphabet for hurricane naming, and whether a Greek alphabet name should be retired as done for a regular name when it meets the criteria for retirement.
The Committee felt that the use of the Greek alphabet was not expected to be frequent enough to warrant any change in the existing naming procedure for the foreseeable future and therefore decided that the naming system would remain unchanged and that the Greek alphabet would continue to be used.
However, after the record-breaking season, the WMO Regional Association IV Hurricane Committee annual session in , decided to end the use of the Greek alphabet and instead, established two lists of supplemental tropical cyclone names, one of the Atlantic, one for the Pacific.
NB: Starting , in lieu of the Greek alphabet, the lists of supplemental tropical cyclones names will be used. The names are used one after the other. The only time that there is a change is if a storm is so deadly or costly that the future use of its name on a different storm would be inappropriate. In the event that more than twenty-one named tropical cyclones occur in a season, a supplemental list of names are used. For a complete list of upcoming and retired storm names, visit the National Weather Service website.
Some typhoon names had multiple appearances in history, so we need to identify which typhoon is the topic of a text using some hints in the text or background knowledge.
This means that a successful natural language processing system of typhoon-related text should resolve the ambiguities of typhoon names, and should solve the problem of "named entity recognition" or "named entity extraction" that automatically identify a typhoon name as the typhoon in history. This problem is apparent in number-based conventions. If we employ the 4-digit convention, it has an obvious problem of year cycle Typhoon may represent the 14th typhoon of year , or maybe Well, this year cycle is not a big problem yet, but the offical record of typhoons had started to be compiled since , so we should expect to have the year problem at least we have passed the halfway of this periodicity anyway.
And, of course, the 2-digit convention like Typhoon No. We often encounter cases where we have to disambiguate whether the typhoon No. To avoid such an ambiguity problem, we adopt a 6-digit convention like Typhoon , which does not have a short cycle problem as stated, at least before the year On the other hand, list-based conventions also have the same kind of problem because a name is chosen from a circular list, which means that the same name will be "recycled" in the future.
For example, on the formation of a new typhoon, we assign a new name from the list of Asian names. This means that after assigning typhoon names, we return to the first name of the list and reuse same names.
Studying past cases reveal that we in fact have 15 typhoons with the name FAYE since Thus the list-based convention cannot avoid the ambiguity problem either. To cope with the ambiguity problem, the typhoon name is sometimes "retired," and removed from the list. This case happens when the typhoon has a severe impact on lives or the economy to the level that is remembered for generations after the devastation.
Whenever a typhoon has had this level of impact, any country affected by the storm can make a request to the World Meteorological Organization WMO that the name of the typhoon be retired to facilitate historic references, legal actions, insurance claim activities, etc.
This convention is exactly like a retired number for a famous sports player to keep memory and avoid confusion. The hurricane season in the Atlantic Basin was the most active hurricane season in history with 27 named storms. Not only the number is large but the impact was also huge, including Hurricane Katrina that struck New Orleans. The list of cyclone names for this basin was therefore not prepared so this cyclone could not be named.
What is the reason of this rare phenomenon? Is this related to the global climate change of the earth? Note It seems that this hurricane is now called Catarina after the name of the place it made landfall.
In contrast to the nameless cyclone, we had many "no-name typhoons" in Japan. This may not be a problem because number-based conventions are far more popular in Japan , but in any case a no-name typhoon sounds a bit strange. Why do we have a typhoon with such a strange name? The reason is that, the certifying organization and the naming organization of a typhoon were different before Namely, in the western north Pacific basin before , when Japan Meteorological Agency JMA , the certifying organization, declares the birth of a typhoon, while Joint Typhoon Warning Center JTWC , the naming organization, did not declare the birth of a typhoon, the international name was not assigned even when the typhoon number was increased.
The decision of the birth of a typhoon was made by experts in each country , so it frequently happens that a typhoon in Japan is not a typhoon in the USA. This is the case that we had a no-name typhoon. This site gives a tentative name NO-NAME for those typhoons, and if you search, you get as many as 82 typhoons in the past. But after , Japan Meteorological Agency starts to be in charge of both decision and naming, so we will see no more "no-name" typhoons in the future.
Japan Only number-based convention Philippines Own list-based convention only used within the country China Transition from number-based convention to list-based convention? Korea Primary number-based convention, and secondary list-based convention?
Taiwan List-based convention is more often used?
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