Global Warming-Hurricane Link Just Hot Air
by David Ridenour
Hurricanes aren't the only things that spin faster with the addition of hot air.
Advocates of the global warming theory seem to spin faster, too - take their recent spin on this summer's hurricanes.
An August article in the San Francisco Chronicle warned, "As the United States experiences more... out-of-season hurricanes like this summer's, more Americans will recognize what the rest of the world has long accepted: Global warming is here, it will get worse..."1
This analysis has a critical flaw: The National Oceanic and Atmospheric Administration (NOAA) says the hurricane season runs from June 1 to November 30.2
That would make summer hurricanes in-season, wouldn't it?
And there's another little problem with the Chronicle warning: Much of the global warming that occurred during the last century occurred from 1900-1940, followed by a cooling period that lasted from about 1940 to 1975.
A comparison of hurricane severity against the warming/cooling trends finds that we had an above average number of hurricanes in the 50s and 60s - when the Earth was cooling.
Hurricane severity is governed by a natural Atlantic Ocean temperature cycle that lasts decades. Following the identified pattern, Atlantic hurricanes were especially prevalent in the 1950s and 1960s, were less so from about 1970 to 1994, and, since 1995, have been prevalent again.3
Talk of a link between global warming and increased incidence of hurricanes is just hot air, nothing more.
As Christopher W. Landsea, a scientist with NOAA's Hurricane Research Division, has noted, "It is highly unlikely that global warming has (or will) contribute to a drastic change in the number and intensity of hurricanes."
Landsea found that the number of intense hurricanes (those reaching Saffir-Simpson scale ratings of 3, 4, or 5) actually decreased in the Atlantic during the 1970s and 1980s.4 And from 1991 to 1994, the Atlantic had fewer hurricanes than any four-year period on record, with an average of less than four hurricanes per year.5
The two most intense hurricanes (based on barometric pressure) to hit the United States since 1900 didn't occur over the past decade, but decades ago. The most intense was the "Labor Day" hurricane of 1935 that hit the Florida Keys. The second most intense was Hurricane Camille, which hit Mississippi, Louisiana and Virginia in 1969. This year's Hurricane Katrina comes in third.6
Measured by wind speed at landfall, Katrina (140 mph) is fourth, following 1969's Camille (190 mph), 1992's Andrew (165 mph) and the 1935 Labor Day hurricane (160 mph).7
Assuming deaths from Katrina remain under 2,500, as now is projected, the deadliest modern hurricanes also were decades ago: the "Galveston" Hurricane of 1900 and the "Lake Okeechobee" Hurricane of 1928, which claimed more than 8,000 and more than 2,500 lives, respectively.
Needless to say, the burning of fossil fuels - which global warming theory advocates say are overheating the planet - was less prevalent in 1933 than now.
Even if the planet does eventually warm, it's not clear that either the incidence or intensity of hurricanes would increase.
Patrick Michaels, a research professor in environmental sciences at the University of Virginia, has noted, "Atlantic hurricanes are much more delicate than their destruction suggests. One thing they cannot tolerate is a west wind blowing into them because it wrecks their symmetry. As a result, their maximum winds decline."9
These are precisely the conditions that exist during El Ninos - weather phenomena that some scientists believe increase with rising global temperatures.
If they are right, this would mean that global warming might be expected to result in less severe hurricanes.
Other studies suggest that higher global temperatures would also result in fewer hurricanes.
A 1990 study of temperature data by Drs. Robert Balling, Sherwood Idso and Randall Cerveny spanning 41 years found that the warmest years had fewer hurricane days, on average, than the coldest years.
These findings are consistent with the earlier historical record. The most severe storms in the North Sea, for example, occurred during the 15th and 16th centuries, after the onset of the Little Ice Age.10
Nature, not man-made global warming, causes hurricanes.
By claiming otherwise, alarmists are generating a few gale-force winds of their own.
# # #
David Ridenour is vice president of the National Center for Public
Policy Research. Comments may be sent to email@example.com.
1 Mark Hertsgaard, "Nuclear Energy Can't Solve Global Warming: Other Remedies 7 Times More Beneficial," San Francisco Chronicle, August 7, 2005.
2 Christopher Landsea, "FAQ: Tropical Cyclones," Atlantic Oceanographic and Meteorological Lab (National Oceanic and Atmospheric Administration), August 13, 2004.
3 For more information, see Christopher W. Landsea, "A Climatology of Intense (or Major) Atlantic Hurricanes," Monthly Weather Review, Volume 121, 1993, http://www.aoml.noaa.gov/hrd/Landsea/climo/, or "Major Hurricanes Predicted to Increase in Years Ahead," by Hillary Mayell, National Geographic News, July 20, 2001, at http://news.nationalgeographic.com/news/2001/07/0719_hurricanes.html.
4 Christopher Landsea, "FAQ: Tropical Cyclones," Atlantic Oceanographic and Meteorological Lab (National Oceanic and Atmospheric Administration), August 13, 2004.
5 David Ridenour, "Don't Like the Weather: Don't Blame Global Warming," The National Center for Public Policy Research, August 1998, http://www.nationalcenter.org/NPA206.html.
6 Doyle Rice, "Hurricane Katrina Stronger Than Andrew at Landfall," USA Today, August 31, 2005, http://www.usatoday.com/weather/stormcenter/2005-08-31-Katrina-intensity_x.htm
7 Doyle Rice, "Hurricane Katrina Stronger Than Andrew at Landfall," USA Today, August 31, 2005, http://www.usatoday.com/weather/stormcenter/2005-08-31-Katrina-intensity_x.htm
8 Patrick J. Michaels, "Sowing the Hurricane Whirlwind," Cato Institute, September 21, 2004, http://www.cato.org/dailys/09-21-04.html.
9 David Ridenour, "Don't Like the Weather: Don't Blame Global Warming," The National Center for Public Policy Research, August 1998, http://www.nationalcenter.org/NPA206.html.