Recent modeling studies show that a change in the strength of this circulation would have a critical effect on temperatures and precipitation in North America, Europe and Africa.
"In addition to measuring the variability of ocean overturning, OSNAP is focused on understanding what factors create those changes," says Lozier.
OSNAP data will facilitate the study of how the northward flow of warm water affects the reduction of Arctic sea ice and the shrinking of the Greenland Ice Sheet.
"Oceanographers have known that overturning circulation is susceptible to changes in the temperature and salinity of surface waters in the sub-polar North Atlantic," says Lozier.
"With increasing ocean temperatures, and increased ice melt that affects the salinity of surface waters, it's important to establish how climate change might affect the strength of overturning circulation."
The oceanographers will deploy moored instruments and sub-surface floats across the sub-polar North Atlantic during the summer of 2014. The measurement period will last until 2018.
"Greenland's margins are a great place to take the pulse of Atlantic overturning circulation in high latitudes," says Straneo.
"This is where equatorward-flowing fresh water from the Arctic meets poleward-flowing warm Atlantic Ocean water--and where the two are progressively cooled and transformed into denser waters.
"Beneath these waters, we can also observe the equatorward flow of even denser waters formed in the Nordic Seas."
The array of instruments will stretch along two lines, from Labrador to southern Greenland and from Greenland east to Scotland.
The instruments will provide scientists with continuous measurements
|Contact: Cheryl Dybas|
National Science Foundation