Meteorologists used up so many Atlantic storm names during the 2005 hurricane season that they may have to create a new back-up list in case supplies are exhausted in future busy years, U.S. forecasters said.
Meteorologists said the busy 2005 season was part of a natural cycle of heightened Atlantic hurricane activity that could last for decades.
Hurricane names are chosen by the United Nation's World Meteorological Organization. Representatives of the 26 nations in the group's Region IV, which covers the Atlantic-Caribbean hurricane belt, will decide which names to retire and what to do about a naming crunch when they meet in Puerto Rico in March, forecasters at the U.S. National Hurricane Center said.
The WMO group compiles six alphabetical lists of 21 storm names each, skipping Q, U, X, Y and Z because not enough names start with those letters. The lists rotate every six years, so the 2005 list will be used again in 2011.
Names are retired and replaced when a storm causes large loss of life or property. "Katrina" will certainly be stricken from the list after 2005, and probably several others, said Frank Lepore, spokesman for the hurricane center.
"The country that is most affected by the storm will request the change," Lepore said.
For the first time since Atlantic hurricanes were given names in 1953, all 21 names were used up this year, which has seen a record 26 tropical storms so far. Forecasters named the last five — Alpha, Beta, Gamma, Delta and Epsilon — from the Greek alphabet which has long been the designated backup list but had never before been used.
"The issue is, what happens if you have to retire a Greek alphabet letter?" Lepore said.
Alpha might be a candidate for retirement because Tropical Storm Alpha caused flooding that killed 33 people in Haiti and nine in the Dominican Republic in late October.
The busy seasons expected over the next two decades raise the prospect of dipping into an incomplete Greek alphabet the next time all 21 official storm names are used up.
"I think the safest thing is to come up with another list and we'll discuss that," said hurricane center director Max Mayfield.
The proposed seventh list would follow the alphabetical pattern as the six now in use but instead of rotating, it would be used as a backup any time an annual list is exhausted.
Hurricanes are given names because it makes it easier to discuss them, especially when relaying information between widely scattered weather stations and ships. Until 1979, only female names were used but now the lists alternate between men's and women's names.
Choosing the names is a bit of an art, the forecasters said. They must be short and easy to pronounce in the all languages spoken in the region — French, Spanish, Dutch, English and Haitian Creole for the Atlantic-Caribbean basin.
"They have to be something that if they're mispronounced, they don't sound very close to something vulgar," Lepore said.