Scientists uncover surprising new pathway for North Atlantic circulationMay 14th, 2009 - 2:21 pm ICT by ANI
Washington, May 14 (ANI): A new study has shown that much of the southward flow of cold water from the Labrador Sea moves not along the deep western boundary current, but along a previously unknown path in the interior of the North Atlantic.
The study was done by co-principal authors Amy Bower, a senior scientist in the WHOI Department of Physical Oceanography, and Susan Lozier, a professor of physical oceanography at Duke University’s Nicholas School of the Environment.
“This new path is not constrained by the continental shelf. It’s more diffuse,” said Bower. “It’s a swath in the wide-open, turbulent interior of the North Atlantic and much more difficult to access and study,” she added.
Since this cold southward-flowing water is thought to influence and perhaps moderate human-caused climate change, this finding may impact the work of global warming forecasters.
Lozier and Bower first conceived of this program eight years ago.
Studies led by Lozier and other researchers had previously suggested cold northern waters might follow such “interior pathways” rather than the conveyor belt in route to subtropical regions of the North Atlantic.
But, testing the idea meant developing an elaborate WHOI-led field program involving the launching of 76 special Range and Fixing of Sound “RAFOS” floats into the current south of the Labrador Sea between 2003 to 2006.
Bower worked with a team at WHOI to build the floats and develop the plan for their deployment.
The “RAFOS” floats were configured to submerge at 700 or 1,500 meters depth - within the layer of the ocean where one constituent of the cold southward-flowing water, called Labrador Sea Water, travels.
They drifted with the currents for two years, recording location information as well as temperature and pressure measurements once a day.
After two years, the floats returned to the surface and transmitted all their data through the ARGOS satellite-based data retrieval system and downloaded to scientists in the lab.
Since the RAFOS float paths could only be tracked for two years, Lozier and her team also used a modeling program to simulate the launch and dispersal of more than 7,000 virtual “e-floats” from the same starting point.
Subjecting those e-floats to the same underwater dynamics as the real ones, the researchers then traced where they moved.
“The new float observations and simulated float trajectories provide evidence that the southward interior pathway is more important for the transport of Labrador Sea Water through the subtropics than the DWBC, contrary to previous thinking,” their report concluded. (ANI)
- How heat is transported to Greenland glaciers - Mar 29, 2011
- Ocean temperature patterns key to climate change - Aug 26, 2012
- Warming oceans drive largest movement of marine species - Jun 26, 2011
- Russia's floating university traces Gulf Stream - Jul 17, 2012
- Altantic home to widespread floating plastic debris - Aug 22, 2010
- Arctic Ocean water is 'warmest it's been for more than 2,000 years' - Feb 01, 2011
- Water flowing into Arctic warmest in 2,000 years - Feb 01, 2011
- Inflow of salt water from Indian Ocean could stabilize climate in Europe - Apr 30, 2011
- Underwater asphalt volcanoes discovered in the Pacific Ocean - Apr 27, 2010
- Expedition to discover colour of the Atlantic Ocean - Mar 11, 2011
- Arctic ice melt prelude to severe winters - Jun 07, 2012
- Ice chunk '4 times Manhattan's size' breaks away from Greenland glacier - Aug 07, 2010
- Footloose glaciers cracking up - Jul 15, 2010
- Bering Strait influenced ice age climate patterns worldwide 100,000 years ago - Jan 11, 2010
- Ocean circulation changes 'more dramatic than previously thought' - Jan 15, 2011
Tags: argos satellite, atlantic circulation, bower, climate change, cold water, continental shelf, conveyor belt, duke university, flowing water, forecasters, labrador sea water, lozier, nicholas school, northern waters, physical oceanography, pressure measurements, principal authors, swath, temperature and pressure, western boundary