Friday, September 12, 2008

How Hurricanes Get Named

Sept. 8, 2008--The Atlantic region is dealing with a steady—and scary—line-up of tropical storms. Hurricane Gustav struck last Monday with a weaker blow than anticipated, then came Hanna. Now, Ike is in effect and Josephine is on her way. So, how do the names for all these hurricanes get chosen?

G, H, I, J—well, alphabetical order is clear, but apparently there's a little more to the selection process. Short and distinguishable names are used to identify storms, instead of the older method of identifying a storm by its latitude and longitude. Naming tropical storms allows for information about them to be easily distributed, especially when multiple storms occur at once.

Every region in the United States has its own naming procedure with a pre-approved set of names familiar to that area. The storm-prone Atlantic and Eastern North Pacific have the most elaborate naming procedures. According to the National Hurricane Center, both regions have their own set of six lists. The lists are used in rotation every six years, meaning the same list of names that was used to name Gustav and company will be used again in 2014.

Each of the six alphabetized lists includes 21 pre-approved names, with the letters Q, U, X, Y and Z excluded. The name of a particular tropical storm indicates how many others have occurred that year. Our friend Gustav, thankfully tamer than his name might suggest, was the seventh storm to hit the Atlantic this year.

Other areas, like the Central and Western Pacific, use a strictly sequential selection method. Lists are not designated by year. If the third name on a list is the last storm to hit, then the first storm of the following year is named by simply picking the next on the list.

There are, of course, exceptions to the rules. When a hurricane's impact becomes too severe, deadly or costly, its name is retired from the list. A new name with the same letter is then added to the list during one of the World Meteorological Organization's annual meetings. Hurricane Katrina of 2005 was one such retiree. Others include: Hurricane Agnes (1972), Hurricane Betsy (1965) and Hurricane Andrew (1992).

The hurricane name game was an all-girls club for quite some time. In the late 19th century, Australian meteorologist Clement Wragge introduced the method of naming tropical storms after women. In 1953, after an international phonetic alphabet was introduced for naming storms, the practice of naming storms after women became common in America. The Atlantic region didn't go co-ed until 1979. And now female and male names are listed alternately in alphabetical order.

In extreme conditions, the Greek alphabet is also an option for naming hurricanes in the Atlantic. As a back-up, storms take on names like Hurricane Alpha and Tropical Storm Beta when all 21 names from that year's pre-approved list have already been used.

And while there have been several tropical storms in the Atlantic this season, here's hoping that Ike is the last name we have to remember.

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