dp
11-06-2004, 02:32 PM
Some comments on the 2004 hurricane season.
The following paragraphs are especially interesting excerpts from a paper by William Gray and his team at Colorado State University, which annually forecasts hurricane activity based on statistical analysis of prior yearsÍ data. I have selected content that especially pertains to Florida and therefore, to The Bahamas. The whole paper can be seen at: http://hurricane.atmos.colostate.edu/forecasts/2004/oct2004/. At the time the paper was written, hurricane Jeanne was yet to be felt....
Denny Parker.
_________________________________
FORECAST OF ATLANTIC HURRICANE ACTIVITY FOR OCTOBER 2004 AND SEASONAL UPDATE THROUGH SEPTEMBER
By: William M. Gray1 and Philip J. Klotzbach2 with special assistance from William Thorson3
Colorado State University
Fort Collins, CO 80523
...It is important that Floridians view this terribly damaging landfall season from a longer period perspective. Overall Florida has been extremely fortunate in recent years. Between 1966-2003 (38 years) the Florida Peninsula has experienced the landfall of only one major hurricane (Andrew, 1992) (Fig.æ13). But in this long major hurricane lull period since the mid-1960s, Florida's population and coastal development has exploded. Few of the new Floridians have experienced a major hurricane hit. Most Floridians were not prepared for this unusual onslaught of four devastating storms in such a short period of time. But old-timers who lived in Florida in the 1930s through the 1950s well remember that Florida used to be hit by many intense storms. Between 1928-1965 (41 years) the Florida Peninsula experienced 14 major hurricane landfalls, (1 per 3 years).
Is Global Warming Involved?
Florida residents should not interpret the four damaging hurricane landfalls to their state in August-September to be related, in any way, to the much publicized human-induced global warming hypothesis. Although an unusual event (likely occurring about once every 100 years), these four strong landfall events are a rare combination of an above-average season of major hurricane activity together with unusually favorable broad-scale steering currents that drove mid-Atlantic tropical cyclones westward instead of allowing them to recurve. Such a combination of high tropical cyclone frequency and special westward steering currents is not frequent but well within the range of natural climate fluctuations and might be considered from a statistical point-of-view as a rare 2 1/2 sigma event. There would be little discussion of this year's hurricanes activity if these four major storms had not made U.S.ælandfall, which could have just as easily occurred
Although the Atlantic basin has been very active this year, as have eight of the last 10 Atlantic basin seasons, the other six global tropical storm basins which account for about 88 percent of the globe's approximately 80 named tropical cyclones per year have not shown a similar increase. In fact, global net tropical cyclone activity has actually shown a small decrease during the last 10 years. If global warming (natural or man-made) were the cause of the increased Atlantic basin activity, we should have seen an increase in the other storm basins as well. This has not occurred.
We believe that the global mean surface temperature changes that have been observed over the last 30 years and over the last century are of mostly natural origin (ocean-forced) and likely not a result of any human influence. We do not attribute Florida's four landfalling hurricanes of the last two months to be related in any way to human influences. :confused:
The following paragraphs are especially interesting excerpts from a paper by William Gray and his team at Colorado State University, which annually forecasts hurricane activity based on statistical analysis of prior yearsÍ data. I have selected content that especially pertains to Florida and therefore, to The Bahamas. The whole paper can be seen at: http://hurricane.atmos.colostate.edu/forecasts/2004/oct2004/. At the time the paper was written, hurricane Jeanne was yet to be felt....
Denny Parker.
_________________________________
FORECAST OF ATLANTIC HURRICANE ACTIVITY FOR OCTOBER 2004 AND SEASONAL UPDATE THROUGH SEPTEMBER
By: William M. Gray1 and Philip J. Klotzbach2 with special assistance from William Thorson3
Colorado State University
Fort Collins, CO 80523
...It is important that Floridians view this terribly damaging landfall season from a longer period perspective. Overall Florida has been extremely fortunate in recent years. Between 1966-2003 (38 years) the Florida Peninsula has experienced the landfall of only one major hurricane (Andrew, 1992) (Fig.æ13). But in this long major hurricane lull period since the mid-1960s, Florida's population and coastal development has exploded. Few of the new Floridians have experienced a major hurricane hit. Most Floridians were not prepared for this unusual onslaught of four devastating storms in such a short period of time. But old-timers who lived in Florida in the 1930s through the 1950s well remember that Florida used to be hit by many intense storms. Between 1928-1965 (41 years) the Florida Peninsula experienced 14 major hurricane landfalls, (1 per 3 years).
Is Global Warming Involved?
Florida residents should not interpret the four damaging hurricane landfalls to their state in August-September to be related, in any way, to the much publicized human-induced global warming hypothesis. Although an unusual event (likely occurring about once every 100 years), these four strong landfall events are a rare combination of an above-average season of major hurricane activity together with unusually favorable broad-scale steering currents that drove mid-Atlantic tropical cyclones westward instead of allowing them to recurve. Such a combination of high tropical cyclone frequency and special westward steering currents is not frequent but well within the range of natural climate fluctuations and might be considered from a statistical point-of-view as a rare 2 1/2 sigma event. There would be little discussion of this year's hurricanes activity if these four major storms had not made U.S.ælandfall, which could have just as easily occurred
Although the Atlantic basin has been very active this year, as have eight of the last 10 Atlantic basin seasons, the other six global tropical storm basins which account for about 88 percent of the globe's approximately 80 named tropical cyclones per year have not shown a similar increase. In fact, global net tropical cyclone activity has actually shown a small decrease during the last 10 years. If global warming (natural or man-made) were the cause of the increased Atlantic basin activity, we should have seen an increase in the other storm basins as well. This has not occurred.
We believe that the global mean surface temperature changes that have been observed over the last 30 years and over the last century are of mostly natural origin (ocean-forced) and likely not a result of any human influence. We do not attribute Florida's four landfalling hurricanes of the last two months to be related in any way to human influences. :confused: