Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Riders on the storm

19.11.2004


Drifting buoys & floats weather hurricanes for better storm prediction



While some are still cleaning up from the series of hurricanes that plowed through the Caribbean and southern United States this season, scientists supported by the Office of Naval Research are busily cleaning up valuable data collected during the storms. The rapid-fire hurricanes barely gave researchers time to rest between flights that took them into the hearts of Hurricanes Frances, Ivan, and Jeanne. As part of a project called CBLAST, for Coupled Boundary Layer/Air-Sea Transfer, researchers air-dropped specially designed instruments into the paths of the hurricanes--and into the hurricanes themselves.

"This season has seen a breakthrough in hurricane and oceanographic research," said ONR program manager Dr. Carl Friehe. "Real-time data sent back by the drifters and floats have created great interest among oceanographers, meteorologists, and hurricane forecasters." Project CBLAST-Hurricane focuses on the energy exchanges between the ocean and atmosphere during a hurricane, and how those interactions affect a storm’s intensity (a separate CBLAST component studies low-wind interactions). By better understanding these energy exchanges, scientists can develop better models to predict a hurricane’s development. A hurricane’s intensity determines the size of the storm surge of water that precedes it--which can pose a significant threat to ships in port.


New instruments that can measure the ocean water’s temperature, salt content, and velocity--before, during, and after a hurricane--are providing a unique view of the conditions that affect a storm’s intensity. While satellites can provide ocean temperature data, they only monitor the "skin" or surface of the ocean down to just 1/8th of an inch. To reach into lower depths, ONR has sponsored the development of new ocean probes by Dr. Eric D’Asaro and Dr. Tom Sanford of the University of Washington Applied Physics Laboratory (Seattle), and Dr. Peter Niiler and Dr. Eric Terrill of Scripps Institution of Oceanography (La Jolla, Ca).

The data collected on water conditions over the course of a hurricane are crucial to forecast modeling because "the ocean is the gasoline for the hurricane’s engine," explained ONR’s Friehe. During the summer and fall, the sun warms the top hundred meters or so of the ocean. Hurricanes only form over these warm ocean regions, where water easily evaporates and is picked up by swirling weather patterns. "In order to build a model that can predict a storm’s development, we need to know exactly how much energy is in the water, as well as how it is distributed by depth and location between Africa and the Caribbean," he said.

The floats from the UW Applied Physics Lab and Scripps are programmed to bob up and down through the upper 200 meters (656 ft) of the ocean, measuring the water’s temperature, salinity, dissolved gases, and velocity. They also monitor underwater sounds as part of a study to develop methods of measuring hurricane force winds and rainfall. The floats from the Applied Physics Lab are deployed in a line perpendicular to a hurricane’s path, so that one is centered on the eye, another is about 50 km (27 nautical miles) to the north of the eye, and a third 100 km (54 nm) to the north. Each time the instruments reach the water’s surface, they transmit data back to scientists using satellite communications.

Drifters from the Scripps team remain on the ocean’s surface, floating like bottles with a message that’s constantly updated as their instruments measure air pressure, wind speed and direction, and sea surface temperature. They can collect data for as long as their batteries continue to function (up to several months) or they can be picked up by passing ships for reuse and downloading of more detailed information than they are able to transmit. The drifters and floats were dropped into the paths of this season’s hurricanes by the U.S. Air Force Reserve 53rd Weather Reconnaissance Squadron (Keesler AFB, Miss.) from two C130J Hercules aircraft. The probes parachuted into the ocean and automatically began taking measurements. They returned time series of ocean profiles that documented the upwelling and mixing caused by the hurricanes. Several of the floats and drift buoys obtained an unprecedented second set of hurricane observations as Hurricane Jeanne followed closely on the path of Frances.

While the drifters and floats weathered the storms from sea level and below, other CBLAST instruments--and researchers--flew through Hurricane Jeanne in two National Oceanic and Atmospheric Administration (NOAA) WP-3D aircraft. From various altitudes throughout the storms, and with the help of fixed and deployed instruments, they collected data on air temperature and pressure, wind speed and direction, and precipitation. The combination of atmospheric and ocean science, technology (GPS, cell phones, miniature computers, etc.), deployment via aircraft, and the need for better hurricane forecasting have all come together in 2004 to mark a sea change in hurricane research, according to Friehe.

NOAA provides project management for CBLAST, as well as researchers, aircraft, flight crews, and other support through its Hurricane Research Division, Aircraft Operations Center, and Office of Oceanic and Atmospheric Research. Researchers from the University of Miami, Rosenstiel School; University of Washington Applied Physics Lab; Scripps Institution of Oceanography; Massachusetts Institute of Technology; and the University of Massachusetts Microwave Remote Sensing Laboratory also participated. The 5-year (FY01-FY05) funding amount for CBLAST Hurricane is: $5.3 M from ONR and $0.7 M from NOAA’s U.S. Weather Research Program (USWRP).

Jennifer Huergo | EurekAlert!
Further information:
http://www.onr.navy.mil

More articles from Earth Sciences:

nachricht Predicting unpredictability: Information theory offers new way to read ice cores
07.12.2016 | Santa Fe Institute

nachricht Sea ice hit record lows in November
07.12.2016 | University of Colorado at Boulder

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>