Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Gulf warm-water eddies intensify hurricane changes

05.10.2005


A possible culprit? Gulf’s "Loop Current"



Scientists monitoring ocean heat and circulation in the Gulf of Mexico during Hurricanes Katrina and Rita have a new understanding of how these tropical storms can gain intensity so quickly: The Gulf of Mexico’s "Loop Current" is likely intensifying hurricanes that pass over eddies of warm water that spin off the main current.

"A positive outcome of a hurricane season like this is that we’ve been able to learn more about the Loop Current and its associated warm-water eddies, which are basically hurricane intensity engines," said Nick Shay, a University of Miami Rosenstiel School of Marine and Atmospheric Science (RSMAS) meteorologist and physical oceanographer.


The Loop Current is a horseshoe-shaped feature that flows clockwise, transferring warm subtropical waters from the Caribbean Sea through the Yucatan Straits into the Gulf of Mexico.

This year, the Loop Current extended deep into the Gulf of Mexico during hurricane season. Currents at this time of year typically become unsteady and pinch off deep, warm eddies, said Shay. The warm water then becomes ideal for hurricanes in the process of intensifying.

"Scientists have known that hurricanes form above the world’s warmest ocean surface waters," said Jay Fein, program director in the National Science Foundation (NSF)’s Division of Atmospheric Sciences, which funded the research. "This study adds new information about hurricanes’ journeys to landfall, and will help to better predict their paths and intensity changes during their final hours over open water."

After Hurricane Katrina and a week before Hurricane Rita, Shay, Peter Black from the NOAA’s Atlantic Oceanographic and Meteorological Laboratory (AOML) and Eric Uhlhorn of the University of Miami/NOAA Cooperative Institute for Marine and Atmospheric Science, deployed Airborne Expendable Conductivity, Temperature and Depth profilers (AXCTDs); Current Profilers (AXCPs); and Bathythermographs (AXBTs) to obtain information on water temperature to depths of up to 3,300 feet (1,000 meters).

The AXCTDs and AXCPs, which were funded by NSF, are dropped from aircraft and measure salinity and currents.

Meteorologists are learning a great deal as hurricanes pass over the deep, warm waters of the Loop Current, Shay said. "We have long been aware that these currents are an important way for the ocean to distribute heat and energy, but until now, we just didn’t have much data on the role they played in building hurricane intensity."

Two days before Hurricane Rita, Black and Rick Lumpkin of AOML, and Peter Niiler of the Scripps Institution of Oceanography, deployed surface drifters that measure surface and subsurface thermal conditions while traveling clockwise around a Loop Current warm eddy just south of La. The eddy was lying in the path of Rita.

"This represents one of the most comprehensive ocean-data sets where two major hurricanes passed through the same region," said Frank Marks, director of NOAA’s Hurricane Research Division. "This series of observations is a testament to how new ocean observations are helping us understand hurricane intensity changes."

"The last time there was a season with two Category 5 hurricanes in the same basin was in 1961 with Carla and Hattie," said Shay. "However, the same phenomenon occurred the year before in 1960 with Donna and Ethel."

Hurricanes Katrina and Rita also have much in common with Hurricane Opal, a category 4 storm that occurred a decade ago, on Oct. 4. During Opal, meteorologists first recognized the pivotal role that deep, warm eddies play in quickly building hurricane intensity. Opal encountered a warm- water eddy in the Gulf of Mexico and strengthened in intensity from Category 1 to Category 4 in just 14 hours.

Cheryl Dybas | EurekAlert!
Further information:
http://www.nsf.gov

More articles from Earth Sciences:

nachricht Predicting eruptions using satellites and math
28.06.2017 | Frontiers

nachricht NASA sees quick development of Hurricane Dora
27.06.2017 | NASA/Goddard Space Flight Center

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Supersensitive through quantum entanglement

28.06.2017 | Physics and Astronomy

X-ray photoelectron spectroscopy under real ambient pressure conditions

28.06.2017 | Physics and Astronomy

Mice provide insight into genetics of autism spectrum disorders

28.06.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>