Destination: Dean

Twelve research buoys designed at Scripps Institution of Oceanography, UC San Diego took on Hurricane Dean and provided more evidence to storm trackers that the devices are an important new tool for measuring and forecasting extreme weather events.

On Aug. 19, a “Hurricane Hunter” C-130 airplane deployed the buoys known as global drifters off Yucatan 350 miles to the west of Dean as the storm slammed Jamaica. Although Dean’s course shifted slightly, many of the instruments still captured its full force at a point when its intensity briefly rated it a Category 5 storm.

“One went right through the eyewall at 130 knots and it performed beautifully,” said Peter Niiler, the Scripps physical oceanographer who has developed the drifters over the past two decades.

The deployment marks the second successful use of the drifters — which measure air pressure, sea surface temperature at depth and other data — in hurricane tracking. After two unsuccessful missions, hurricane trackers placed 20 in the path of 2005’s Hurricane Rita and received a suite of vital data.

“This means we have a robust system,” said Niiler, in reference to the successful hurricane missions.

The Atlantic Oceanographic and Meteorological Laboratory (AOML), a division of the National Oceanic and Atmospheric Administration, administers the global drifter program that included the Hurricane Dean deployment. There are more than 1,200 similar drifters deployed worldwide.

Rick Lumpkin, an AOML oceanographer who collaborates with Niiler on the drifter deployments, said their performance during Hurricane Dean proved their value as a forecasting tool.

“The drifters measured wind and air pressure data characterizing thestructure of Hurricane Dean, and measured changes in sea surface and subsurface temperatures as the storm passed the drifter array,” Lumpkin said. “These data will be used to calibrate and validate models seeking to improve hurricane intensity forecasts.”

— Robert Monroe