sail-world.com
 
 
News Home Cruising Photo Gallery Video Gallery

 

Sail-World.com : Eddies found to be deep, powerful modes of ocean transport

Eddies found to be deep, powerful modes of ocean transport

'Black smoke rises vigorously at vents when the hot, chemically-altered seawater mixes with the cold, oxygenated bottom water. The hydrothermal alterations to seawater occurring at these relatively isolated locations affect the global ocean chemical budget and sustain thriving and strange communities, including these giant tubeworms, Riftia pachyptila, and gastropod limpets grazing on their tubes'    Woods Hole Oceanographic Institution (WHOI) ©

Researchers from Woods Hole Oceanographic Institution (WHOI) and their colleagues have discovered that massive, swirling ocean eddies - known to be up to 500 kilometers across at the surface--can reach all the way to the ocean bottom at mid-ocean ridges, some 2,500 meters deep, transporting tiny sea creatures, chemicals, and heat from hydrothermal vents over large distances.

The previously unknown deep-sea phenomenon, reported in the April 28 issue of the journal Science, helps explain how some larvae travel huge distances from one vent area to another, said Diane K. Adams, lead author at WHOI and now at the National Institutes of Health.

'We knew these eddies existed,' said Adams, a biologist. 'But nobody realized they can affect processes on the bottom of the ocean. Previous studies had looked at the upper ocean.'

Using deep-sea moorings, current meters and sediment traps over a six-month period, along with computer models, Adams and her colleagues studied the eddies at the underwater mountain range known as the East Pacific Rise. That site experienced a well-documented eruption in 2006 that led to a discovery reported last year that larvae from as far away as 350 km somehow traveled that distance to settle in the aftermath of the eruption.

The newly discovered depth of the powerful eddies helps explain that phenomenon but also opens up a host of other scientific possibilities in oceans around the world. 'This atmospherically generated mechanism is affecting the deep sea and how larvae, chemical and heat are transported over large distances,' Adams said.

The eddies are generated at the surface by atmospheric events, such as wind jets, which can be strengthened during an El Niño, and 'are known to have a strong influence on surface ocean dynamics and production,' say Adams and Dennis J. McGillicuddy from WHOI, along with colleagues from Florida State University, Lamont Doherty Earth Observatory, and the University of Brest in France. But this 'atmospheric forcing…is typically not considered in studies of the deep sea,' they report.

Moreover, the eddies appear to form seasonally, suggesting repeated interactions with undersea ridges such as the Eastern Pacific Rise. The models 'predict a train of eddies across the ocean,' Adams said. 'There may be two to three eddies per year at this location,' Adams said. Each one, she says, 'could connect the site of the eruption to other sites hundreds of miles away.' Elsewhere, she adds, 'there are numerous places around the globe where they could be interacting with the deep sea.'

Shortly after an eruption, vent life replenishes itself through the settlement of larvae sometimes from distant sources. Small tubeworms (tevnia) and limpet gastropods begin to cover the new glassy basalt crust. -  Woods Hole Oceanographic?nid=83147 Institution (WHOI) ©  

In her 2010 report on larvae traveling great distances to settle at the eruption site, WHOI Senior Scientist Lauren S. Mullineaux , along with Adams and others, suggested the larvae traveled along something like an undersea superhighway, ocean-bottom 'jets' travelling up to 10 centimeters a second. But conceding that even those would not be enough to carry the larvae all that distance in such a short time, the researchers speculated that large eddies may be propelling the migrating larvae even faster.

Adams’s current work follows up on that possibility. 'The mechanism we found helps explain what we saw in the first paper,' Adams said.

It is the larger picture, over longer periods of time, however, that Adams and her colleagues find particularly intriguing. 'Transport [of ocean products] could occur wherever…eddies interact with ridges—including the Mid-Atlantic Ridge, the Southwest Indian Ridge, and the East Scotia Ridge—and the surrounding deep ocean,' the researchers say.

And because the eddies appear to form repeatedly, the high-speed, long-distance transport can last for months. 'Although the deep sea and hydrothermal vents in particular are often naively thought of as being isolated from the surface ocean and atmosphere, the interaction of the surface-generated eddies with the deep sea offers a conduit for seasonality and longer-period atmospheric phenomena to influence the ‘seasonless’ deep sea,' Adams and her colleagues write.

'Thus, although hydrothermal sources of heat, chemical and larval fluxes do not exhibit seasonality there is potential for long-distance transport and dispersal to have seasonal to interannual variability.'

The study was funded by the National Science Foundation, WHOI, and the U.S. Department of Defense.

The lead author, Diane K Adams (foreground), helps the crew of the R/V Atlantis haul in one of the moorings equipped with current meters and a time series sediment trap (shown here) whose contents revealed the unexpected influence of eddies on the transport of hydrothermal vent chemicals and biology. -  Woods Hole Oceanographic?nid=83147 Institution (WHOI) ©  

Woods Hole Oceanographic Institution website




by Woods Hole Oceanographic Institution

  

Click on the FB Like link to post this story to your FB wall

http://www.sail-world.com/index.cfm?nid=83147

12:07 PM Wed 4 May 2011 GMT






Click here for printer friendly version
Click here to send us feedback or comments about this story.


News - USA and the World







Audi Melges 20 World Championship - Classic Garda conditions on day 2 by International Audi Melges 20 Class Association,
























Audi Melges 20 World Championship - Alessandro Rombelli's 'STIG' leads by International Audi Melges 20 Class Association,




























Aldo Alessio Regatta - Three days of tight racing by Erik Simonson, Pressure-Drop.US,








Maxi Yacht Rolex Cup 2014 - Quality fleet for Maxi Classic
Sailing Champions League - which is Europe's best sailing club?
Weta fun at the Wine & Roses Regatta
Extreme Sailing Series: The Wave, Muscat claims victory on Cardiff Bay
International 14 World Championships 2015: Not just for boys
Rio de Janeiro achieves 50% treatment of sewage outflow *Feature
2014 AWT Quatro Desert Showdown - Event memorable videos
2014 18' Skiff Int Regatta: Day 1 at San Francisco - Reversal on beach
Emirates Team NZ: Last race boost cannot save team from table bottom
PWA Alacati World Cup - Furious slalom is upon us
J/111 World Championships - The Winner is Shmokin Joe!
J/24 US National Championship - Victory for Will Welles’ Cougar
Extreme Sailing Series: View the Final Day's action - Replay
NYYC Grandmasters Team Race - Reign continues for Noroton Yacht Club
WSSR announces new World Record Around Britain and Ireland
IFDS Worlds 2014 - Final day photos by Tim Wilkes
2014 Detroit Cup - Morvan wins
Newport Bucket Regatta 2014 -Images by George Bekris
IFDS Worlds 2014 - Final report: USA qualifies for Rio 2016
Extreme Sailing Series: Absent With-Out Leave – Ben Ainslie Racing
2014 IFDS World Championship - New champions claim medals   
2014 IFDS World Championships - Sunday’s race images by Tim Wilkes   
Shark World Championships underway in Toronto   
Anna Tunnicliffe: Alinghi second o'all - Extreme Sailing Series, Day 3   
Formula Kite World Championships - Nocher and Bridge crowned Champions   
Emirates Team NZ: Frustrating Day 3 in Extreme Sailing Series, Cardiff   
Extreme Sailing Series: Light winds help The Wave Muscat - Day 3   
Extreme Sailing Series 2014 Act five - Absent without leave – the wind   
IFDS Worlds 2014 - Images: Race day five   
Herreshoff Classic Regatta 2014 - Images by Ingrid Abery   
Youth Olympics - Gold to Argentinean and Chinese Techno 293 racers   
Youth Olympics Games Nanjing - Double Youth Olympic Gold for Singapore   
Sevenstar Round Britain and Ireland Race 2014 - Two Handers celebrate   
Audi Melges 20 U.S. National Championship 2014 - Brazilian dance party   
IFDS Disabled Sailing Worlds Day 5 - USA fighting for Rio 2016 Berths   
J/111 World Championship 2014 - Day 4: Shmokin Joe consolidates lead   
Anna Tunnicliffe: Alinghi on top - Extreme Sailing Series, Day 2   
2014 IFDS World Championships - Breezy frustrations   
2014 Detroit Cup - Down to the final four   
Sevenstar Round Britain and Ireland Race - Every finisher's a winner   


For this week's complete news stories select    Last 7 Days
   Search All News
For last month's complete news stories select    Last 30 Days
   Archive News







Sail-World.com  


















Switch Default Region to:

Social Media

Asia

Australia

Canada

Europe

New Zealand

United Kingdom


http://www.sail-world.com/event_images/image/Twitter_logo_small.png http://www.sail-world.com/event_images/image/FaceBook-icon.png  http://www.sail-world.com/event_images/image/RSS-Icon.png

United States

Cruising Northern

Cruising Southern

MarineBusiness World

PowerBoat World

FishingBoating World

 

Contact

Commercial

News

Search

Contact Us

Advertisers Information

Submit news/events

Search Stories/Text

Feedback

Advertisers Directory

Newsletter Archive

Photo Gallery

 

Banner Advertising Details

Newsletter Subscribe

Video Gallery

Policies

 

 

 

Privacy Policy

 

 


Cookie Policy

 

 



This site and its contents are © Copyright TetraMedia and/or the original author, photographer etc. All Rights Reserved.  Photographs are copyright by law.  If you wish to use or buy a photograph contact the photographer directly.
XLXL NEW US
LocalAds   DE  ES  FR  IT