March 28, 2008

Naming Hurricanes

Stupid Question ™
Oct. 17, 2002
By John Ruch
© 2002

Q: Who decides what hurricanes are named?
—Der Kommissar

A: Storm-naming is done by 11 regional weather services worldwide, all working from lists and/or formulas drawn up under the supervision of the United Nation’s World Meteorological Organization (WMO) in Switzerland.
What these systems actually name are tropical cyclonic storms. That means any large, rotating low-pressure system originating in the tropics with minimum sustained winds of 39 mph. Traditionally, a tropical cyclone with winds of at least 74 mph is called a hurricane in the Atlantic and a typhoon in the Pacific.

Naming started around 1950, when long-range observation and tracking of cyclones became possible. Names have served to get people in threatened areas to focus on the coming storm.

US meteorologists began by naming them after the military phonetic alphabet (at the time, Able, Baker, Charlie….).

In 1953, the National Weather Service replaced this with female first names. Naming things after wives and girlfriends was a common World War II soldiers’ practice. Another influence may have been a popular 1941 novel called “Storm,” in which a hurricane is referred to as “Maria.”

The highly memorable female-name system was widely imitated, and expanded to include male first names in 1978 after feminist protests.
Spanish and French names joined the list in 1979, when the WMO internationalized the naming process. (This led to controversy when the Spanish name “Israel” joined the name list.)

The classic US naming system, covering the Caribbean, Gulf of Mexico and North Atlantic, uses six lists of 21 names each. (Names beginning with Q, U, X, Y and Z are not used due to their scarcity.)

One list is used each year, with the names assigned to cyclones in alphabetical order as needed. If there are more than 21 storms in a year, the Greek alphabet (Alpha, Beta, Gamma….) is used as a back-up.
After six years are up, the lists are simply used again.

However, the names of historically destructive storms that will still be remembered six years later, like Andrew (1992) and Camille (1969), are retired for at least 10 years to avoid confusion. They are replaced by new names with the same first letter and gender.

Most other weather services use a list of names in a cycle that is not restricted by year, so that every name gets used up. The newest, for the Western North Pacific/South China Sea region, uses not only first names but also colorful words like Parma (a ham and liver dish in Macao).

The only naming holdout is the Bay of Bengal/Arabian Sea area, which uses a location code (BOB or ARB) and four digits signifying the year and the cyclone’s place in the year’s cyclone list. For example, 2002’s first cyclone in the Bay of Bengal was BOB 0201.

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