What is a hurricane?
Have you ever been in a bad storm?
Do you know someone who has been in a hurricane?
Alvin, Barbara, Cosme, Dalila, Erick, Flossie, Octave, Tico... What do all these names have in common? These are just some of the names that the World Meteorological Organization (WMO) has assigned to one of the most destructive of natural forces, the hurricane. Toqualify as a hurricane, a tropical storm has to have winds in excess of 74 miles per hour. These winds blow in a large spiral around a relatively calm center known as the "eye". The eye is usually 20 to 30 miles wide, out of which the storm may extend over 400 miles.
Why bother naming hurricanes, you might be wondering. Why not just number them?. Naming hurricanes is crucial, and for obviousreasons: names provide a quick reference for weather forecasters and public alike. After all, if a Category 5 hurricane is bearing down on you, you want to know exactly when to get out of its way! "Hurricane 574579A is on its way" doesn't have quite the same instant "recognizability" as, say, "Hurricane Katrina", the storm that almost destroyed New Orleans in 2005.
The history of naming hurricanesis a complicated one. In the West Indies, for example, hurricanes were named after the particular saint's day on which the hurricane occurred. So you would get names like Saint Michael or Saint Lucia. During the Second World War, military meteorologists named storms informally, often after girlfriends and wives! In the 1950s, tropical cyclones originating in the North Atlantic Ocean were givennames derived from the phonetic alphabet, like Able, Baker, Charlie; all men's names. In 1953, the National Weather Service (NWS) switched to using female names for storms. However, after pressure from feminists, who found it offensive, male names were added to the list in the late 1970s. Sexual equality wins the day! Well, at least among hurricanes.
Unlike the Atlantic Ocean, the Pacific is aslightly different story. Interestingly, from January 2000, the WMO's Typhoon Committee (comprised of nations around the Pacific Rim) began giving Asian names to their storms. The differentiating factor is that this set of names relates not to people, but flowers, animals, plants, and even foods. In addition, while the Asian Pacific list is organized alphabetically like the Atlantic lists, the namesare arranged according to the contributing nations in the Typhoon Committee and not according to the names themselves.
So how does the WMO choose names for hurricanes? Basically, the WMO chooses one name for each letter of the alphabet, except for Q, U and Z. The WMO uses six lists in rotation. The same lists are reused every six years. Another interesting fact is that the only time the WMO adds anew name to the list is if a hurricane is very deadly or costly. In this case, the name is "retired" and a new name is chosen. Katrina has, of course, been retired.
Just how long have hurricanes been around? One of the first known records appears in Mayan hieroglyphics. In fact, it was the Mayans that gave us the word "hurricane". It derives from the word "Hurakan". Hurakan was the name of aMayan deity who blew back the sea and brought forth dry land. Yet, despite their long history, hurricanes only began to be seriously studied about a hundred years ago. Much of this research was dedicated to finding ways to stop them; if not at source, then at least when they were still out at sea.
Various US administrations have funded projects to find ways to stop hurricanes, so far withoutsuccess. Scientists do not hold out much hope of ever being able to stop them, as the weather systems that cause hurricanes are too large to affect. Now the focus is more on perfecting early warning systems. Certainly, hurricane "mapping" is proving very effective in tracking the path of hurricanes, and warning people about when the storm will reach them and what category it is likely to weigh in...