A Brief History
On September 16, 1961, Hurricane Esther became the target of the United States National Research Project to drop Silver Iodide into an active hurricane in an attempt to reduce the magnitude of the storm. When eight cylinders were dropped into the eyewall of the storm near Puerto Rico, a 10% drop in windspeed was noted, giving rise to Project Stormfury. (The dropping of Silver Iodide crystals was tried from 1962 to 1983 until ended because it really did not work.) Today in the aftermath of Hurricane Harvey and Hurricane Irma, we will tell you at least 10 fascinating facts about hurricanes.
1. Hurricane, what it is:
A ‘hurricane’ is a Tropical Cyclone that occurs either in the Atlantic Ocean (including arms of the Atlantic such as the Gulf of Mexico) or the Northeaster portion of the Pacific Ocean, mainly around the West coast of North America. Similar giant rotating (cyclonic) tropical storms are called Typhoon, Cyclone, or Tropical Storm. Unlike storms that occur farther North or South that are powered by temperature differences in the air, hurricanes are fueled by evaporating water from warm ocean waters. The storms may range from as little as 62 miles in diameter to over 1200 miles in diameter. The rotation is caused by the rotation of the Earth, and such storms are normally not found within 5 degrees of Latitude of the Equator. The storms are also characterized by extremely heavy rains and high winds of at least 74 miles per hour sustained for at least a minute. These storms are unusual South of the Equator.
2. Hurricane Season:
Perhaps you have heard the term, “Hurricane Season.” On the East Coast of the United States and the Caribbean, the season goes from June 1st until November 30th when the ocean waters are warm enough to trigger the storms. On the West Coast of the US and Mexico, the season lasts from May 15th until November 30th. Of course, there is no law that says a hurricane has to fall within the designated season!
3. Hurricane Ratings:
Hurricanes are rated from 1 to 5, with 5 being the most powerful, as measured by sustained wind speed. Sometimes a less “powerful” storm can be much more devastating than one bearing a higher rating, because of its size, the amount of rain that falls, it duration and the location it hits. Category 1 storms have a sustained wind of at least 74 mph for 1 minute or 64 mph for 10 minutes, Category 2 means sustained winds of at least 96 or 84 mph respectively, Category 3 requires wind speeds of 110 or 97 mph respectively and is called a “Major Hurricane,” Category 4 means sustained winds of 130 mph for a minute or 114 mph for 10 minutes, and the top of the pile is Category 5, with minimum sustained winds of 158 mph for 1 minute or 140 mph for 10 minutes. There is no upper limit to wind speed for rating a hurricane. There is also a Hurricane Severity Index based on the size and intensity of the storm, with the current record holder being Hurricane Carla in 1961 with a combined score of 42 points. (For comparison, Hurricane Katrina scored 36 points and ranks tied for 4th in Atlantic hurricanes.)
4. How Hurricanes are named:
Caribbean hurricanes used to be named after the Saints day that the storm was observed on, and later the US used latitude and longitude to identify storms. During World War II the US military began using female names for the storms and by 1953 the practice became routine by the National Hurricane Center. The World Meteorological Organization now handles the naming of storms, and alternates between male names in even numbered years and female names in odd numbered years (surely a coincidence!) since 1978 in the Pacific and 1979 in the Atlantic. Storms now alternate between male and female names. A list of names is developed and storms are designated in alphabetical order according to the list. Names can be recycled for reuse, unless the named storm is a memorable one, then the name is retired. The letters Q, U, X, Y, and Z are not used.
5. Connotations of the name, Hurricane:
People are so impressed with hurricanes that the name of the storm has been used to dub sports teams, such as the Miami (Florida) Hurricanes, a name evoking an unstoppable force, power and fury. Ditto for the Carolina Hurricanes hockey team. The same logic applies to naming the Hawker built World War II (Britain) fighter planes Hurricane and Typhoon (and Tempest, too). Plus, you have people being dubbed “Hurricane,” such as the famous boxer Rubin “Hurricane” Carter, well known for the 1975 Bob Dylan song, “Hurricane,” and the 1999 major motion picture, The Hurricane, starring Denzel Washington. Then you have the comics page character from “The Born Loser,” Hurricane Hattie. Even kids cartoon character Peter Potamus roars his famous “Hippo, Hurricane, Holler!” There have also been roller coasters named “Hurricane” or some derivative, such as “Cyclone.” The fascination with the name, “Hurricane,” also extends to “Hurricane Lamps/Lanterns” (normally fueled by kerosene or lamp oil).
6. Highest recorded hurricane winds:
Hurricane wind gusts of over 200 mph are unusual, but not rare, although sustained wind speeds over 200 mph are quite rare. The highest wind gust speed for a Cyclone was measured in Australia in Cyclone Olivia, 1996, at 253 mph. In the Atlantic, the highest wind gust recorded was 215 mph, most recently in 2017 by Hurricane Irma. The highest sustained winds measured in Atlantic hurricanes was 190 mph in Hurricane Allen (1980) and 185 mph in Hurricane Irma (2017). (Various sources list other Atlantic hurricane gusts of over 215 mph, and numbers are hard to verify.)
7. Hurricanes can cause tornadoes:
In 2004, Hurricane Ivan spawned a record 120 tornadoes! (No evidence of any of those becoming a “Sharknado!”) And yes, Hurricane Irma has spawned tornadoes in “Florida and at least 1 tornado in Georgia. A final tally is not yet available for Irma.
8. How Hurricanes cause damage:
Of course you think of wind when you think of hurricane damage, and normally wind is the main culprit, blowing buildings and trees apart in spectacular fashion. Often, however, the main damage is caused by flooding from heavy rains and “storm surge.” Hurricane Harvey that struck Texas in 2017 is a good example of a hurricane wreaking havoc by flooding and incredibly heavy rains (4 or 5 feet worth!). Damage from storm surge is caused by the low pressure and wind that draws ocean water ashore much higher than normal high tide. The record for storm surge in the US was during Hurricane Katrina in 2005 at Mississippi, a massive almost 28 feet higher than normal high tide. Scientists estimate that New England (including New York City) could theoretically suffer a storm surge over 30 feet, as high as 38 feet in “ideal” conditions! Obviously, anything approaching these numbers would be catastrophic. Tops for Florida and the Carolinas is estimated at a possible 32 foot storm surge. The incredibly damaging storm surge from Hurricane (aka, Super Storm) Sandy in 2012 was “only” a bit more than 13 feet, so you can imagine how terrible a 30 foot surge would be.
9. Costliest Hurricane:
By far the most expensive hurricane as measured by monetary loss was Hurricane Katrina in 2005 at over $108 billion. Second was Hurricane/Super Storm Sandy in 2012 at $74 billion, and third is Hurricane Harvey of 2017 at $70 billion (probably not yet firm numbers for Harvey). Of course, inflation has something to do with monetary loss. We’ll have to wait a little for the price tag from the massive Hurricane Irma currently taking its toll.
10. Deadliest Atlantic Hurricane:
The aptly named “Great Hurricane” of 1780 erased as many as 22,000-27,000 lives as it tore through the Lesser Antilles islands in the Caribbean, including the Island of Hispaniola. The storm ended up all the way to the East Coast of Canada. Worse yet, there were 2 other severe hurricanes that year. The death toll of the Great Hurricane eclipsed the death toll of most decades’ worth of hurricanes. Winds were estimated at 200 mph. The second worst hurricane by number of deaths was Hurricane Mitch in 1998, causing most of its killing in Honduras and Central America before moving up to Florida. The deadliest hurricane to hit the US mainland was the Galveston hurricane of 1900, which killed about 8000-12,000 people, the deadliest natural disaster in US History.
Question for students (and subscribers): Have you ever been in a hurricane? Please let us know in the comments section below this article.
Your readership is much appreciated!
For more information, please see…
Lauber, Patricia. Hurricanes: Earth’s Mightiest Storms. HOUGHTON MIFFLIN, 2000.
The featured image in this article, a map of rainfall totals from Hurricane Esther, is in the public domain in the United States because it is a work prepared by an officer or employee of the United States Government as part of that person’s official duties under the terms of Title 17, Chapter 1, Section 105 of the US Code.