Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists with Hawaii Ocean Mixing Experiment Closing in on Puzzle of Ocean Energy

18.07.2003


Using an array of technologies and instruments, scientists in the Hawaii Ocean-Mixing Experiment (HOME), a nearly $18 million National Science Foundation-sponsored project focused on pinpointing, dissecting, and analyzing ocean mixing, captured intriguing phenomena including undersea waves that spanned nearly 1,000 feet


Temperature was recorded at several depths on a mooring set in 1,453 meters of water along the Hawaiian Ridge during the Home project. Twice on this day, at the same frequency as the tide, the graphic shows displacements of about 300 meters. For comparison, the surface tidal range in Honolulu is less than a meter.


Scientists from six institutions, including Scripps Institution of Oceanography at the University of California, San Diego, are closing the gap in deciphering one of the most puzzling aspects of the world’s oceans. "Ocean mixing," the complex motions of seawater that span large-scale phenomena down to tiny, centimeter-sized turbulent motion, serves a key role in redistributing heat throughout the oceans. Although ocean mixing is a key element in the climate system and important for sea life for dispersing nutrients, a mystery remains in accounting for how its processes unfold.

A new research paper in the journal Science describes ocean mixing in unprecedented detail. Using an array of technologies and instruments, scientists in the Hawaii Ocean-Mixing Experiment (HOME), a nearly $18 million National Science Foundation-sponsored project focused on pinpointing, dissecting, and analyzing ocean mixing, captured intriguing phenomena including undersea waves that spanned nearly 1,000 feet. The paper in the July 18 issue of Science is the first effort by HOME investigators to collectively document their findings.

The HOME scientists chose the Hawaiian Ridge, a 1,600-mile largely submerged volcanic mountain chain that stretches from the Big Island of Hawaii to Midway Island, due to its rough topography, including large underwater mountains and valleys. Such areas are sometimes referred to as the "stirring rods" of the oceans.



Prior to the HOME project, areas such as the Hawaiian Ridge were hypothesized to be a major energy pathway for ocean mixing turbulence. Traveling across the Pacific, oceanic tides crash upon the Hawaiian Ridge and dissipate. To help explain how such areas help mix warm low latitude waters and cool polar waters, HOME investigators undertook a comprehensive survey to track the cascade of ocean energy and turbulence.

"One of the triumphs of the HOME experiment was being able to measure the cascade from thousands of meters down to centimeter scales," said Dan Rudnick, a professor of oceanography at Scripps and lead author of the Science paper. "I don’t think this effort is rivaled in terms of measuring detailed dissipation over a topographic feature."

HOME scientists, using the Scripps research vessel Roger Revelle, the flagship of the Scripps fleet; the towed instrument SeaSoar, which took a variety of measurements of upper ocean properties; a new Doppler sonar developed by Scripps Professor Robert Pinkel; and a variety of other instruments and equipment, found that the Hawaiian Ridge is indeed a site with vastly increased ocean mixing. They documented undersea internal wave energy that was enhanced 10 times at the Hawaiian Ridge as compared with normal open ocean areas.

With the details of the cascading processes described in the Science paper, the coauthors helped further close the gap of how energy is dissipated in ocean mixing. But the paper notes that the energy puzzle is not completely solved with these results. Even more energy for ocean mixing must be found elsewhere.

"Our conclusion is interesting because we found that there was certainly a lot of energy loss occurring at the Hawaiian Ridge, but much of it propagates away and doesn’t get dissipated at the ridge. So we’re approaching closure of this phenomenon," said Rudnick. "But until we have a firmer understanding of this process-until we get a better handle on mixing-climate models will be of limited use."

In addition to Rudnick, coauthors of the study include Joseph P. Martin, Robert Pinkel, and Luc Rainville from Scripps Institution; Timothy J. Boyd, Gary D. Egbert, Jody M. Klymak, Murray D. Levine, James N. Moum, and Jonathan D. Nash from Oregon State University; Russell E. Brainard from the Pacific Islands Fisheries Science Center; Glenn S. Carter, Michael C. Gregg, Eric Kunze, Craig M. Lee, and Thomas B. Sanford from the University of Washington; Peter E. Holloway from the University of New South Wales, Australia; and Douglas S. Luther and Mark A. Merrifield from the University of Hawaii.

Planning for the HOME project began in 1996 and the final field phases of the project were concluded last month. Scientific analysis of the data set is planned through 2005.

Scripps Institution of Oceanography at the University of California, San Diego, is one of the oldest, largest, and most important centers for global science research and graduate training in the world. The scientific scope of the institution has grown since its founding in 1903. A century of Scripps science has had an invaluable impact on oceanography, on understanding of the earth, and on society. More than 300 research programs are under way today in a wide range of scientific areas. Scripps operates one of the largest U.S. academic fleets with four oceanographic research ships and one research platform for worldwide exploration. Now plunging boldly into the 21st century, Scripps is celebrating its centennial in 2003.

Mario Aguilera | Scripps Institution
Further information:
http://scripps.ucsd.edu
http://scripps100.ucsd.edu

More articles from Earth Sciences:

nachricht A new 3D viewer for improved digital geoscience mapping
20.09.2016 | Uni Research

nachricht The significance of seaweed
16.09.2016 | King Abdullah University of Science and Technology

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: OLED microdisplays in data glasses for improved human-machine interaction

The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP has been developing various applications for OLED microdisplays based on organic semiconductors. By integrating the capabilities of an image sensor directly into the microdisplay, eye movements can be recorded by the smart glasses and utilized for guidance and control functions, as one example. The new design will be debuted at Augmented World Expo Europe (AWE) in Berlin at Booth B25, October 18th – 19th.

“Augmented-reality” and “wearables” have become terms we encounter almost daily. Both can make daily life a little simpler and provide valuable assistance for...

Im Focus: Artificial Intelligence Helps in the Discovery of New Materials

With the help of artificial intelligence, chemists from the University of Basel in Switzerland have computed the characteristics of about two million crystals made up of four chemical elements. The researchers were able to identify 90 previously unknown thermodynamically stable crystals that can be regarded as new materials. They report on their findings in the scientific journal Physical Review Letters.

Elpasolite is a glassy, transparent, shiny and soft mineral with a cubic crystal structure. First discovered in El Paso County (Colorado, USA), it can also be...

Im Focus: Complex hardmetal tools out of the 3D printer

For the first time, Fraunhofer IKTS shows additively manufactured hardmetal tools at WorldPM 2016 in Hamburg. Mechanical, chemical as well as a high heat resistance and extreme hardness are required from tools that are used in mechanical and automotive engineering or in plastics and building materials industry. Researchers at the Fraunhofer Institute for Ceramic Technologies and Systems IKTS in Dresden managed the production of complex hardmetal tools via 3D printing in a quality that are in no way inferior to conventionally produced high-performance tools.

Fraunhofer IKTS counts decades of proven expertise in the development of hardmetals. To date, reliable cutting, drilling, pressing and stamping tools made of...

Im Focus: Launch of New Industry Working Group for Process Control in Laser Material Processing

At AKL’16, the International Laser Technology Congress held in May this year, interest in the topic of process control was greater than expected. Appropriately, the event was also used to launch the Industry Working Group for Process Control in Laser Material Processing. The group provides a forum for representatives from industry and research to initiate pre-competitive projects and discuss issues such as standards, potential cost savings and feasibility.

In the age of industry 4.0, laser technology is firmly established within manufacturing. A wide variety of laser techniques – from USP ablation and additive...

Im Focus: New laser joining technologies at ‘K 2016’ trade fair

Every three years, the plastics industry gathers at K, the international trade fair for plastics and rubber in Düsseldorf. The Fraunhofer Institute for Laser Technology ILT will also be attending again and presenting many innovative technologies, such as for joining plastics and metals using ultrashort pulse lasers. From October 19 to 26, you can find the Fraunhofer ILT at the joint Fraunhofer booth SC01 in Hall 7.

K is the world’s largest trade fair for the plastics and rubber industry. As in previous years, the organizers are expecting 3,000 exhibitors and more than...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Experts from industry and academia discuss the future mobile telecommunications standard 5G

23.09.2016 | Event News

ICPE in Graz for the seventh time

20.09.2016 | Event News

Using mathematical models to understand our brain

16.09.2016 | Event News

 
Latest News

Chains of nanogold – forged with atomic precision

23.09.2016 | Life Sciences

New leukemia treatment offers hope

23.09.2016 | Health and Medicine

Self-assembled nanostructures hit their target

23.09.2016 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>