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

 

Sail-World.com : Icelandic current could influence ocean's response to changes

Icelandic current could influence ocean's response to changes

'Buoyant spheres will hold the moorings upright when they are placed in the North Icelandic Jet during the upcoming field program to measure the characteristics of the current.'    Woods Hole Oceanographic Institution (WHOI) ©

Woods Hole Oceanographic Institution’s international team of researchers, which includes physical oceanographers, has confirmed the presence of a deep-reaching ocean circulation system off Iceland that could significantly influence the ocean’s response to climate change in previously unforeseen ways.

The current, called the North Icelandic Jet (NIJ), contributes to a key component of the Atlantic Meridional Overturning Circulation (AMOC), also known as the 'great ocean conveyor belt,' which is critically important for regulating Earth's climate. As part of the planet’s reciprocal relationship between ocean circulation and climate, this conveyor belt transports warm surface water to high latitudes where the water warms the air, then cools, sinks, and returns towards the equator as a deep flow.

Crucial to this warm-to-cold oceanographic choreography is the Denmark Strait Overflow Water (DSOW), the largest of the deep, overflow plumes that feed the lower limb of the conveyor belt and return the dense water south through gaps in the Greenland-Scotland Ridge.

Northern part of Denmark Strait showing the location of the newly discovered deep current in relation to the known existing pathway of dense water. -  Jack Cook, Woods Hole Oceanographic Institution  

For years it has been thought that the primary source of the Denmark Overflow is a current adjacent to Greenland known as the East Greenland Current. However, this view was recently called into question by two oceanographers from Iceland who discovered a deep current flowing southward along the continental slope of Iceland. They named the current the North Icelandic Jet and hypothesized that it formed a significant part of the overflow water.

Now, in a paper published in the Aug. 21 online issue of the journal Nature Geoscience, the team of researchers—including the two Icelanders who discovered it—has confirmed that the Icelandic Jet is not only a major contributor to the DSOW but 'is the primary source of the densest overflow water.'

'In our paper we present the first comprehensive measurements of the NIJ,' said Robert S. Pickart of WHOI, one of the authors of the study. 'Our data demonstrate that the NIJ indeed carries overflow water into Denmark Strait and is distinct from the East Greenland Current. We show that the NIJ constitutes approximately half of the total overflow transport and nearly all of the densest component.

The researchers used a numerical model to hypothesize where and how the NIJ is formed. 'We’ve identified a new paradigm,' he said. 'We’re hypothesizing a new, overturning loop' of warm water to cold.

The North Icelandic Jet shown in cross-section view adjacent to the continental slope of Iceland. -  Jack Cook, Woods Hole Oceanographic Institution  

The results, Pickart says, have 'important ramifications' for ocean circulation’s impact on climate. Climate specialists have been concerned that the conveyor belt is slowing down due to a rise in global temperatures. They suggest that increasing amounts of fresh water from melting ice and other warming-related phenomena are making their way into the northern North Atlantic, where it could freeze, which would prevent the water from sinking and decrease the need for the loop to deliver as much warm water as it does now. Eventually, this could lead to a colder climate in the northern hemisphere.

While this scenario is far from certain, it is critical that researchers understand the overturning process, he said, to be able to make accurate predictions about the future of climate and circulation interaction. 'If a large fraction of the overflow water comes from the NIJ, then we need to re-think how quickly the warm-to-cold conversion of the AMOC occurs, as well as how this process might be altered under a warming climate,' Pickart said.

'These results implicate local water mass transformation and exchange near Iceland as central contributors to the deep limb of the Atlantic Meridional Overturning Circulation, and raise new questions about how global ocean circulation will respond to future climate change,' said Eric Itsweire, program director in the U.S. National Science Foundation (NSF)’s Division of Ocean Sciences, which funded the research.

The Research Council of Norway also funded the analysis of the data.

Pickart and a team of scientists from the U.S., Iceland, Norway, and the Netherlands are scheduled to embark on Aug. 22 on a cruise aboard the WHOI-operated R/V Knorr to collect new information on the overturning in the Iceland Sea.

R/V Knorr navigates through the Iceland Sea while taking measurements of the North Icelandic Jet. -  Woods Hole Oceanographic?nid=87732 Institution (WHOI) ©  

'During our upcoming cruise on the Knorr we will, for the first time, deploy an array of year-long moorings across the entire Denmark Strait to quantify the NIJ and distinguish it from the East Greenland Current,' Pickart said. 'Then we will collect shipboard measurements in the Iceland Sea to the north of the mooring line to determine more precisely where and how the NIJ originates.'

In addition to Pickart, authors of the Nature Geoscience study include Michael A. Spall, and Daniel J. Torres of WHOI, lead author Kjetil Våge, a graduate of the MIT-WHOI joint program now with University of Bergen, Norway, Svein Østerhus and Tor Eldevik, also of the University of Bergen, Norway, and Héðinn Valdimarsson and Steingrímur Jónsson—the two discoverers of the NIJ—of the Marine Research Institute in Reykjavik, Iceland.

Woods Hole Oceanographic Institution website

The Woods Hole Oceanographic Institution is a private, independent organization in Falmouth, Mass., dedicated to marine research, engineering, and higher education. Established in 1930 on a recommendation from the National Academy of Sciences, its primary mission is to understand the ocean and its interaction with the Earth as a whole, and to communicate a basic understanding of the ocean's role in the changing global environment.




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=87732

8:56 PM Thu 25 Aug 2011 GMT






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


News - USA and the World

Touch2Play had the great fortune of participating in what would be the largest yet gathering of J88’s to date. Quantum Key West Race Week would serve as a chance to see how boats lined up against one another in conditions that covered the full range. For this event we had Rob and Sandy Butler, Steve Leibel, Keven Piper, Coleen Walsh and myself, Larry Huibers. ... [more]  

As the Barcelona World Race leaders race to the Crozet Islands, once again their paths have diverged – Neutrogena around 200 miles to the south-west of first-placed Cheminées Poujoulat on the water, and gaining around 40 miles in the past 24 hours. ... [more]  

For the Tokyo 2020 Paralympic Games the International Paralympic Committee (IPC) will announce on Saturday (31 January) at 10:00 CET the final line-up of sports. ... [more]  

On a high octane first day of the ISAF Sailing World Cup Miami on Monday (26 January) Giles Scott, Alison Young and the Paralympian Sonar trio of John Robertson, Hannah Stodel and Steve Thomas saw the best possible start to their 2015 sailing seasons with double race victories. ... [more]  

On the opening day of racing at ISAF Sailing World Cup Miami, presented by Sunbrella, it was sunny and bright. It was storming and raining sideways. It was sunny and bright. ... [more]  

On the opening day of racing at ISAF Sailing World Cup Miami, presented by Sunbrella, it was sunny and bright. It was storming and raining sideways. It was sunny and bright. ... [more]  

RC44 World Championship Leg 1 gets underway on 24th March until 29th March 2015. The RC 44 Class is unlike any 40 foot sailing yacht ever designed, and the reason for that is simple. She is a high performance one design yacht created for top level racing in international regattas. If one was to compare this concept to racing cars, then we would be talking about the F1, NASCAR or similar. ... [more]  

On Day 1 of the ISAF Sailing World Cup Miami, Presented by Sunbrella, America's premier Olympic and Paralympic classes regatta, featured the full range of what sailing in Miami has to offer. Over 850 sailors enjoyed strong breeze for the duration of the day, in addition to a brief but powerful rainstorm. ... [more]  

ISAF Sailing World Cup Miami - Giles Scott (GBR) said last week that he hoped his unbeaten run would continue, and based on Monday’s form at the Sailing World Cup Miami, the 2014 World and European Finn Champion is giving it a pretty good shot ... [more]  

ISAF Olympic classes regatta Miami 2015 images provided by photographer Ingrid Abery. ... [more]  

Team Alvimedica won a Leg 3 podium place in China after some of the closest racing ever seen in the history of the Volvo Ocean Race. The Turkish-American team protected their position in the final stretch to Sanya, carefully navigating a course peppered with fishing boats along the Vietnamese coast and across the South China Sea to cap off a well-sailed leg to clinch third. ... [more]  

The finish of Leg 3 of the Volvo Ocean Race in Sanya, China just before noon on January 27, 2015 marked an unbelievable end to a magnificent leg for Dongfeng Race Team. After leading the fleet virtually all the way from Abu Dhabi to Sanya in China, over more than 5,000 miles of intense ocean racing, Dongfeng finally crossed the finish line in first place ... [more]  

Winner of Leg 3 of the Volvo Ocean Race, Dongfeng, have released footage taken from a drone launched from the Volvo Ocean Race yacht, as she sails in light airs on the last days of Leg 3 of the race. It is believed to be the first time a drone, launched from a competitor, has been used in a major ocean race. ... [more]  

World sailing history was created earlier today when Dongfeng Race Team became the first Chinese yacht to have a win in a premier trans-ocean racing event. Her win was also a first in the 41-year history of the Volvo Ocean Race. At 1131hrs UTC the Chinese flagged entry emphatically won Leg 3 in their home port of Sanya to take the overall leadin the 40,000nm event with six stages to go. ... [more]  

On the morning of the 26th of January, the Maersk Line ship MV Stockholm delivered the Team Vestas Wind's damaged VO65 to the port in Genoa, Italy. From here she will be taken to the Persico building facilty where the rebuild of the wrecked boat will be undertaken. The team's goal is to rejoin the race in Lisbon, Portugal in June, 2015. ... [more]  

Sir Richard Branson’s Virgin Group is considering backing Sir Ben Ainslie’s America’s Cup bid, in a move that would propel the fortunes of the Olympic gold medallist yet further. Sir Ben is believed to have asked the Virgin billionaire to consider backing the venture when he and his new wife, Georgie Thompson, spent time on Sir Richard’s Necker Island in January. ... [more]  

To the 91st 2015 Bell's Beer Bayview Mackinac Race significant changes have been made in order to enhance the race experience, and by the looks of it, sailors are embracing them wholeheartedly. ... [more]  

Alpari World Match Racing Tour - Monsoon Cup preview by Alpari World Match Racing Tour
The final event of the 2014 Alpari World Match Racing Tour, Monsoon Cup Malaysia, is to take place in its new home of Johor, the southernmost state of Malaysia, over 10th-14th February. In addition to being the grand finale of the Tour, the event will also see the 2014 ISAF Match Racing World Champion crowned. ... [more]  

In the Barcelona World Race the two lead boats are preparing for a gruelling 3,500-mile game of chase across the Southern Ocean, until the next natural gateway of the course, Cape Leeuwin in south-west Australia. ... [more]  

Quantum Key West Race Week provided the opportunity for the GC32s to make a spectacular debut in the USA. During the five days of racing held in balmy temperatures off the southernmost tip of Florida, crews experienced a range of conditions. ... [more]  

40 year old Charles Caudrelier the skipper of race leader Dongfeng was a major figure of the winning French team Groupama in 2011-12 . With the Dongfeng team now approaching Sanya, almost unstoppable, its worthwhile hearing from Volvo Ocean Race CEO Knut Frostad who is hugely pleased with the current on water situation. ... [more]  

Volvo Ocean Race. The northerly drag race continues, with the stable light wind forecast to drop slightly. The boats have all remained in position, if anything cementing their places with gaps between them increasing slightly through the night. ... [more]  

Volvo Ocean Race Leg 3 - Sailing in a straight line was never supposed to be as tense as this. We’ve been pointing at Sanya for almost a day now and fortunately, Alvimedica, MAPFRE, and Brunel far enough back to not be in AIS range anymore. The problem is they’re not in AIS range anymore. ... [more]  

Volvo Ocean Race Leg 3 - After what can only be described as a frustrating few days of wind and current conditions in the Malacca Strait, the shipping lanes we had to pass were a bit more entertaining as it was upwind which meant some tacking. ... [more]  

Volvo Ocean Race: Leg 3 Finish - Video - Delayed feed by Richard Gladwell, Sail-World.com/nz
Tune in here to see the finish of Leg 3 of the Volvo Ocean race in Sanya. Will sailing history be made? Can Dongfeng become the first Chinese flagged yacht to win a Leg in a Round the World Race? ... [more]  

2015 ISAF Sailing World Cup Miami - Bigger than ever in 2015, with an atmosphere crackling with adrenaline, the ISAF Sailing World Cup Miami, Presented by Sunbrella, was ground zero on Sunday as competitors from 63 countries made their final preparations. ... [more]  

The Chinese entry Dong looks set to create sailing sailing history when she finishes first on Leg 3 of the Volvo Ocean Race, Sanya in two days time. Includes video Currently Dongfeng is 250 nm to the finish line in Sanya and the chasing pack with ADOR ahead in second place 55+ nm behind the Chinese team. ... [more]  

The first of the iconic Great Capes has been passed in the Barcelona World Race with Cheminées Poujoulat rounding the Cape of Good Hope earlier this morning. Bernard Stamm and Jean Le Cam passed 20°E around 400 miles south of Cape Agulhas – the southernmost tip of Africa – at 0935am (UTC) today and have begun the Indian Ocean leg of their race around Antarctica. ... [more]  

The Classic 18fters were racing again on Saturday on Sydney harbour. Michael Chittenden caught the action from a shore vantage point. ... [more]  

When race leader Dongfeng rounded Singapore 60+ nautical miles ahead of the chasing pack, it looked like the final 1200 miles of Leg three would be a procession but over the last day, the Volvo Ocean race leg from Abu Dhabi to Sanya China appears to have tightened incredibly. ... [more]  

US Sailing and Rolex USA announced last week that the 2014 Rolex Yachtswoman of the Year is Stephanie Roble. Her accomplishments on the water last year were recognized by the selection panel for her versatility; her accomplishments as a skipper and as a crew; and her competitive successes on a variety of platforms, sailing against both men and women. ... [more]  

Barcelona World Race - The first of the Great Capes is fast-approaching, with the leading boats in the Barcelona World Race expected to pass the longitude of the Cape of Good Hope at the tip of South Africa tomorrow. As they pass 20°E, the Atlantic Ocean will deliver its verdict – did Cheminées Poujoulat’s east-bound track or Neutrogena’s southerly gamble pay off? ... [more]  

Mardi Gras may not be for another month but US Sailing’s National Sailing Programs Symposium (NSPS) kicked it off early for Oakcliff Sailing this year. This evening, Oakcliff received The Captain Joe Prosser Award, given to an organization that has made an exemplary contribution toward improving the quality and safety in the training or instruction of sailors. ... [more]  

20 Nations head for 2015 St.Maarten Heineken Regatta
Volvo Ocean Race - Less than 500 miles to go
2015 Quantum Key West Race Week - Fantastic finish
Barcelona World Race: Weather beacons launched midrace
2015 Quantum Key West Race Week - Day 5
Mount Gay Round Barbados Race – Gala prizegiving marks end of event
2015 Quantum Key West Race Week - Day 5 images by Ingrid Abery
Volvo Ocean Race Leader - Dongfeng - the right place at the right time
ISAF Youth Match Racing World Championship - Notice Of Race online
Currently doing scheduled maintenance.
Volvo Ocean Race: Changes to Team Vestas Wind crew
McDougall+McConaghy Moth Worlds: Highlight video released
America's Cup: Oracle crew mate lodges complaint against Tienpont
2015 Quantum Key West Race Week - Day 4 images by Ingrid Abery
2015 ISAF Sailing World Cup Miami - US Sailing Team preview
Quantum Key West Race Week 2015 - A great day
Volvo Ocean Race: Jump seat and Pro-Am race spots up for auction
Lauderdale Olympic Classes Regatta overall
Volvo Ocean Race - Dongfeng? Race Team suffer? damage
America's Cup: Italy to host first America's Cup World Series regatta
Breeze and Sunshine at Quantum Key West Race Week   
Images of the Millennium Cup and Bay of Islands Sailing Week - Day 1:   
2015 Mount Gay Rum Round Barbados Race – Three records broken   
St.Maarten Heineken Regatta - Simplified logistics and fun themes   
2015 Quantum Key West Race Week - Day 3 images by Ingrid Abery   
Millennium Cup: Racing in the picturesque Bay of Islands   
Volvo Ocean Race - Up up and away   
Barcelona World Race - 'Haves' and 'Have Nots'   
Volvo Ocean Race Leg 3 update from Jack Bouttell onboard Dongfeng   
ISAF Sailing World Cup Miami - Game time!   
Extreme Sailing Series™ 2015 – Ninth year ready to rock!   
Foiling GC32s Key West Race Week images by Ingrid Abery   
Mount Gay Rum Round Barbados Race - Crews prepare for big race   
2015 Quantum Key West Race Week - Day 2   
2015 Quantum Key West Race Week - A challenging day   
America's Cup: Spithill leads Oracle reconnaissance team in Bermuda   
Extreme Sailing Series announces new teams and venues for 2015   
Barcelona World Race - Leaders enter the fastest section of the course   
Martinique Surf Pro - Must attend event in the world surfing circuit   
New York Yacht Club Invitational Cup preview   


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