muddocktor
13 Aug 2005, 2:13am
I'm a subscriber to a weekly feed from Rigzone.com and today's edition had a link to this very interesting article about Hurricane Ivan from last year. (http://www.rigzone.com/news/article.asp?a_id=24305) It seems that researchers had dropped some sensors in the predicted path of the storm and they got back some surprizing information. Here's a few quotes from the article for those that don't want to read the whole article:
An array of underwater sensors dropped in the path of Hurricane Ivan last fall has given Navy researchers new appreciation for how powerful tropical cyclones can be.
Even as it was weakening to maximum sustained winds of 132 mph in the cooler waters of the northern Gulf of Mexico, Ivan generated waves of more than 90 feet, and perhaps as high as 132 feet.
"We measured a 91-footer" on the forward face of Ivan, when the storm was centered 75 miles south of Gulfport, Miss. on Sept. 15, said William Teague, a researcher at the Naval Research Laboratory at the Stennis Space Center in Mississippi. The measurement represents the distance from the top, or crest, of the wave and its bottom, or trough. Instruments also recorded dozens of waves larger than 50 feet as the storm passed. These may be the tallest, most extreme waves ever measured with modern instruments, suggesting that earlier estimates for maximum wave heights for hurricanes were too low, Teague noted.
Wave height as the storm approached the continental shelf was calculated from water-pressure data collected as the storm passed over sensors inside flying-saucer-shaped pods that were laid on the ocean floor at depths of 190 and 290 feet.
The devices, which have a low profile to avoid being snagged by fishing trawlers, somewhat resemble marine barnacles that cling to rocks, piers and boat hulls, and thus have been dubbed "barnys" by the researchers.
The sensors also revealed that Ivan generated currents moving faster than 6 feet a second.
David Wang, lead author of the study published Friday in the journal Science, said the waves captured by the devices probably were only about 85 percent of the maximum wave heights found at the strongest right-hand quadrant of the storm. That means that Ivan's waves could have been as tall as 132 feet.
After riding out a strong tropical storm on a jackup rig last month with winds around 70 mph, I can very well believe this too. We had 35 foot seas for a few hours during the worst of the storm and in only 140 feet water depth.
An array of underwater sensors dropped in the path of Hurricane Ivan last fall has given Navy researchers new appreciation for how powerful tropical cyclones can be.
Even as it was weakening to maximum sustained winds of 132 mph in the cooler waters of the northern Gulf of Mexico, Ivan generated waves of more than 90 feet, and perhaps as high as 132 feet.
"We measured a 91-footer" on the forward face of Ivan, when the storm was centered 75 miles south of Gulfport, Miss. on Sept. 15, said William Teague, a researcher at the Naval Research Laboratory at the Stennis Space Center in Mississippi. The measurement represents the distance from the top, or crest, of the wave and its bottom, or trough. Instruments also recorded dozens of waves larger than 50 feet as the storm passed. These may be the tallest, most extreme waves ever measured with modern instruments, suggesting that earlier estimates for maximum wave heights for hurricanes were too low, Teague noted.
Wave height as the storm approached the continental shelf was calculated from water-pressure data collected as the storm passed over sensors inside flying-saucer-shaped pods that were laid on the ocean floor at depths of 190 and 290 feet.
The devices, which have a low profile to avoid being snagged by fishing trawlers, somewhat resemble marine barnacles that cling to rocks, piers and boat hulls, and thus have been dubbed "barnys" by the researchers.
The sensors also revealed that Ivan generated currents moving faster than 6 feet a second.
David Wang, lead author of the study published Friday in the journal Science, said the waves captured by the devices probably were only about 85 percent of the maximum wave heights found at the strongest right-hand quadrant of the storm. That means that Ivan's waves could have been as tall as 132 feet.
After riding out a strong tropical storm on a jackup rig last month with winds around 70 mph, I can very well believe this too. We had 35 foot seas for a few hours during the worst of the storm and in only 140 feet water depth.