Tucson, AZ (PRWEB) October 21, 2005 -- According to the National Oceanic and Atmospheric Administration (NOAA), hurricanes destroyed approximately $73 billion in property, and were responsible for more than 13,000 deaths in the 20th century. Furthermore, current hurricane climatology and other data show that damaging major hurricanes are predicted to continue to occur over the next two decades.
In an effort to better predict hurricane intensity and thus save lives, a team of scientists from Vaisala’s Thunderstorm conducted a study from 2001 to 2003 that linked lightning trends near the center of hurricanes to hurricane intensity. The study combined eyewall lightning data gathered with Vaisala’s Long-range Lightning Detection Network (LLDN), which measures lightning strikes from cloud to ground, with data reported by the National Hurricane Center (NHC) in moderate-to-strong hurricanes.
A Vaisala LLDN data program was recently developed to correlate with NHC’s hurricane data. Vaisala and NHC forecasters can now observe high cloud-to-ground (CG) lightning rates within hurricane eyewalls, including Hurricane Katrina, Hurricane Rita and Hurricane Wilma.
Scientists found that, while lightning does not always occur in the eyewall of a hurricane, when it does occur it may be a sign of change within the hurricane’s inner-core structure that could help forecast storm intensity. Lightning outbreaks in the eyewalls of hurricanes often occurred during rapid changes in hurricane intensity.
Vaisala researchers were able to apply their hypotheses to Hurricane Charley in 2004. Eyewall lightning data were analyzed for the nineteen hours preceding landfall in southwest Florida. Low to moderate rates of eyewall lightning occurred as Charley intensified at a moderate rate. As the primary eyewall of Charley contracted and the storm rapidly intensified, eyewall flash rates increased dramatically. The LLDN was able to track the increase in lightning flashes along with their intensity, providing evidence that lightning might help predict hurricane intensity.
“This could be an important breakthrough for forecasters because detailed structures within the eyewalls of hurricanes are often obscured on visible and infrared satellite imagery,” explained Nicholas W.S. Demetriades, applications specialist for Vaisala. “Current instrumentation over the tropical oceans cannot monitor the detailed eyewall structure of a hurricane continuously; however, with the findings of this study, it may now be possible to monitor important features of the eyewall that impact hurricane intensity longer.”
Demetriades said Vaisala’s scientists will continue to work with the NHC and other hurricane researchers on applications of lightning data for hurricane intensity forecasting. “The more data we can gather with respect to lightning’s connection to hurricane intensity, the better prepared forecasters and the general public can be when these storms hit.”
The Vaisala Group is an international technology company that develops and manufactures electronic measurement systems and equipment for meteorology, environmental sciences, traffic safety and industry. Vaisala employs over 1,000 professionals and achieved net sales of EUR 180.6 million in 2004. In 2004, exports outside Finland accounted for 97% of net sales. Vaisala's A-series shares are listed on the Helsinki Exchange (HEX).
Further information:
USA:
Scott Sternberg, Thunderstorm Data Services Business Manager, tel +1 520 806 7300
Nicholas W.S. Demetriades, Thunderstorm Applications Specialist, tel +1 520 806 7300
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