SOFAR float trajectories from an experiment to measure the Atlantic cross equatorial flow (1989-1990)

View/ Open
Date
1992-08Author
Richardson, Philip L.
Concept link
Zemanovic, Marguerite E.
Concept link
Wooding, Christine M.
Concept link
Schmitz, William J.
Concept link
Price, James F.
Concept link
Metadata
Show full item recordCitable URI
https://hdl.handle.net/1912/855Location
Deep Western Boundary CurrentDOI
10.1575/1912/855Keyword
SOFAR floats; Equatorial currents; Deep Western Boundary Current; Oceanus (Ship : 1975-) Cruise; Columbus Iselin (Ship) CruiseAbstract
Neutrally buoyant SOFAR floats at nominal depths of 800, 1800, and 3300 m were tracked for 21 months in the vicinity of
western boundary currents near 6N and at several sites in the Atlantic near 11N and along the equator. Trajectories at 1800 m show a
swift (>50 cm/sec), narrow (100 km wide) southward-flowing Deep Western Boundary Current (DWBC) extending from 7N to the
equator. At times (February-March 1989) DWBC water turned eastward and flowed along the equator and at other times (August-September 1990) the DWBC crossed the equator and continued southward. The mean velocity near the equator was eastward from
February 1989 to February 1990 and westward from March 1990 to November 1990. Thus the cross-equatorial flow in the DWBC
appeared to be linked to the direction of equatorial currents which varied over periods of more than a year. No obvious DWBC nor
swift equatorial current was observed by 3300 m floats.
Eight-hundred-meter floats revealed a northwestward intermediate level western boundary current although flow patterns were
complicated. Three floats that significantly contributed to the northwestward flow looped in anticyclonic eddies that translated up
the coast at 8 cm/sec. Six 800 m floats drifted eastward along the equator between 5S and 6N at a mean velocity of 11 cm/sec; one
reached 5W in the Gulf of Guinea, suggesting that the equatorial current extended at least 35-40° along the equator. Three of these
floats reversed direction near the end of the tracking period, implying low frequency fluctuations.
Collections
Suggested Citation
Technical Report: Richardson, Philip L., Zemanovic, Marguerite E., Wooding, Christine M., Schmitz, William J., Price, James F., "SOFAR float trajectories from an experiment to measure the Atlantic cross equatorial flow (1989-1990)", 1992-08, DOI:10.1575/1912/855, https://hdl.handle.net/1912/855Related items
Showing items related by title, author, creator and subject.
-
An exploration of the North Atlantic current and its recirculation in the Newfoundland basin using SOFAR floats
Owens, W. Brechner; Zemanovic, Marguerite E. (Woods Hole Oceanographic Institution, 1990-07)Trajectories and time series of velocity, temperature, and pressure are presented for 13 neutrally-buoyant, acoustically tracked (SOFAR) floats that were launched in May and June, 1986 in the Newfoundland Basin by the ... -
MODE SOFAR float in situ data summary
Voorhis, Arthur D.; Benoit, Raymond R. (Woods Hole Oceanographic Institution, 1974-06)Ten SOFAR floats were instrumented during the MODE field experiment to record pressure, temperature, and vertical water displacement during a four month drift. This report describes the acquisition and reduction of this ... -
SOFAR float Mediterranean outflow experiment data from the second year, 1985-86
Zemanovic, Marguerite E.; Richardson, Philip L.; Valdes, James R.; Price, James F.; Armi, Laurence (Woods Hole Oceanographic Institution, 1988-09)In October, 1984, the Woods Hole Oceanographic Institution SOFAR float group began a three-year-long field program to observe the low frequency currents in the Canary Basin. The principal scientific goal was to learn how ...