Every so often, Mother Nature likes to throw a buzz saw up the Gulf of Mexico — a sort of not-so-friendly reminder of who’s really in charge. In preparation, windows are boarded up, bathtubs filled with water and generators checked and double-checked. Oh, it must be hurricane season.
The big names, we all remember: Camille, Frederic, Ivan, Katrina — storms that brought destruction in the form of powerful winds, driving rain, unstoppable storm surge and even tornadoes. (In 2004, Hurricane Ivan spawned a record 127 twisters.) Like it or not, the hurricane is a fact of life on the Gulf Coast, so it’s a weather phenomenon worth understanding. Think you already know everything about tropical cyclones? Think again.
THE RAINS DOWN IN AFRICA
Hurricanes have been described as heat machines, taking thermal energy from the ocean and converting it into mechanical energy in the form of winds. But most storms form over land; according to researchers, 85 percent of hurricanes begin as disturbances in the atmosphere over West Africa.
TURN THE WORLD UPSIDE DOWN
Tropical cyclones in the northern hemisphere spin counterclockwise, while those in the southern hemisphere spin clockwise. This phenomenon, which occurs because of the earth’s rotation, is called the Coriolis effect.
ON A SCALE OF 1 TO 5…
A hurricane’s strength can be measured by its maximum sustained wind speed or its lowest barometric pressure. The Saffir-Simpson hurricane wind scale classifies storms into five categories based on the intensity of their sustained winds. It is said that development of the scale, in 1971, was inspired by the extensive damage of Hurricane Camille in 1969.
LOCATION, LOCATION, LOCATION
Hurricanes, along with typhoons and cyclones, fall under a category of meteorological events known as tropical cyclones. The three storm types differ only in location: hurricanes occur in the Atlantic Ocean and northeastern Pacific, typhoons in the northwestern Pacific, and cyclones in the south Pacific and Indian Ocean.
EYE DO DECLARE!
When a band of air starts rotating faster than others in a hurricane, an updraft is created from the ocean’s surface to the top of the storm, and a storm eye is formed. Usually about 30 miles in diameter, the eye is a space of mostly calm weather, although the most severe weather conditions are found along its perimeter.
A stormy history
- Spanish explorers of the 16th century adopted the word “hurakán, ” meaning “god of evil” or “god of storm, ” from a native group in the Caribbean called the Arawak. This group likely adopted the word from the Mayans, whose creator god Hurakan was responsible for storms and floods.
- Following a Mobile hurricane on July 5, 1906, a writer for the Mobile Register downplayed the national hysteria: “Newspapers have been known to print in red ink and largest letters ‘Mobile Is Wiped off the Map!’ but it has never happened, and if we judge by what has been experienced in the past, it will never happen. Mobile is the most comfortable place we know of in which to have an attack of hurricane.”
- In 1953, the United States began naming hurricanes in order to reduce confusion. Only female names were used for Atlantic hurricanes until 1979, making Hurricane Frederic one of the first male-named hurricanes to strike the U.S. If a hurricane is particularly costly or deadly, its name is retired from further use.
- According to the Encyclopedia of Alabama, hurricanes hit Alabama approximately once every 7.5 years and make landfall on the Alabama coast once every 16 years. Tropical cyclone season extends from May to October. Historically, September 10 is a peak day for hurricane activity.
- Hurricane Ivan made landfall at Gulf Shores in 2004 with an official wind speed of 120 mph. In 1979, Hurricane Frederic officially clocked 132 mph, but an unofficial wind speed of 145 mph was reported on the Dauphin Island Bridge.
text by Breck pappas
