SYNOP

[IES arrays on satellite image of Gulf Stream]Synoptic Ocean Prediction Experiment
(SYNOP)

The Synoptic Ocean Prediction Experiment (SYNOP) was a major observational and modeling program designed to understand the physics governing large amplitude meandering of the Gulf Stream and the shedding and interactions of rings east of Cape Hatteras to the Grand Banks. The moored instrumentation program included the small Inlet Array near Cape Hatteras, the Central Array near 68W, the East Array near 55W, and the 50W Array. Observations in the different arrays were made between 1987 and 1990 with some overlapping periods between arrays.

The URI, UNC and UM groups maintained the Inlet and Central Arrays. The Inlet Array, consisting of 9 inverted echo sounders (IESs) and 5 deep current meters, was designed to monitor the inflow conditions as the Gulf Stream leaves the continental margin. These instruments were in place from October 1987 to September 1990. The Central Array had two different deployment configurations, but the largest and longest configuration consisted of 24 IESs, 12 of which included bottom pressure gauges. The Central Array also included 12 tall current meter moorings, each with four levels (400, 700, 1000, and 3500 m) instrumented. Three of the moorings had upward-looking acoustic doppler current profilers with pressure and temperature sensors mounted above the topmost current meter. This configuration remained in place from May 1988 to August 1990.

[Gulf Stream abyssal cyclone]One of the most interesting findings of this experiment was the presence of strong deep cyclones and anitcyclones beneath the Gulf Stream. The spin-up of the deep flow field occurred during the passage of steep meander crests and troughs of the Gulf Stream. The velocities at 3500 m depth often were as high as 35-40 cm/s during these strong events. While strong velocities had previously been observed under the Gulf Stream, the association of these strong velocities with an organized deep flow field was not understood prior to the SYNOP observations. Click on the image for details and animations of several events.

 

 

 

Principal Investigators

John. M. Bane, University of North Carolina, Chapel Hill
William E. Johns, University of Miami
Thomas J. Shay, University of North Carolina, Chapel Hill
D. Randolph Watts, University of Rhode Island, Narragansett

Marine Scientist

Scott Lindstrom, Presently at Space Science and Engineering Center, University of Wisconsin-Madison

URI Graduate Students

Meghan Cronin, PhD 1993; presently at PMEL/NOAA
Yuguang He, MS 1993
Stephan D. Howden, PhD 1996; presently at University of Southern Mississippi
Hyun-Sook Kim, MS 1991, PhD 1994

This material is based upon work supported by the National Science Foundation under Grant # OCE87-17144 and by the Office of Naval Research under Contracts N00014-87K-0235, N00014-90J-1568, and N00014-90J-1548.

Link to the Virtual Poster: Strong Abyssal Eddies Coupled to the Meandering Gulf Stream.

Relevant Publications

  • Cronin, M. Eddy-mean flow interaction in the Gulf Stream at 68W. Part II: Eddy forcing on the time-mean flow. J. Phys. Oceanogr., 26:2132–2151, 1996. (doi:10.1175/1520-0485(1996)026%3C2132:EMFIIT%3E2.0.CO;2)
  • Cronin, M., and D. R. Watts. Eddy-mean flow interaction in the Gulf Stream at 68W. Part I: Eddy energetics. J. Phys. Oceanogr., 26:2107–2131, 1996. (doi:10.1175/1520-0485(1996)026%3C2107:EFIITG%3E2.0.CO;2)
  • Cronin, M., K. L. Tracey, and D. R. Watts. Mooring motion correction of SYNOP central array current meter data. GSO Technical Report 92-4, University of Rhode Island, 1992. 115 pp. (PDF)
  • Fields, E., and D. R. Watts. The SYNOP experiment: Inverted echo sounder data report for June 1989 to September 1990. GSO Technical Report 91-2, University of Rhode Island, 1991. (PDF)
  • Fields, E., and D. R. Watts. The SYNOP experiment: Inverted echo sounder data report for May 1988 to August 1989. GSO Technical Report 90-2, University of Rhode Island, 1990. (PDF)
  • He, Y., D. R. Watts, and K. L. Tracey. Determining geostrophic velocity shear profiles with inverted echo sounders.J. Geophys. Res., 103(C3):5607–5622, 1998. (doi:10.1029/97JC03439)
  • Howden, S. D., and D. R. Watts. Jet streaks in the Gulf Stream. J. Phys. Oceanogr., 29:1910–1924, 1999. (doi:10.1175/1520-0485(1999)029%3C1910:JSITGS%3E2.0.CO;2)
  • Howden, S. D. The three dimensional secondary circulation in developing Gulf Stream meanders. J. Phys. Oceanogr., 30:888–915, 2000. (doi:10.1175/1520-0485(2000)030%3C0888:TTDSCI%3E2.0.CO;2)
  • Johns, W. E., T. J. Shay, J. M. Bane, and D. R. Watts. Gulf Stream structure, transport, and recirculation near 65W. J. Geophys. Res., 100(C1):817–838, 1995. (doi:10.1029/94JC02497)
  • Kim, H.-S., and D. R. Watts. An observational streamfunction in the Gulf Stream. J. Phys. Oceanogr., 24:2639–2657, 1994. (doi:10.1175/1520-0485(1994)024%3C2639:AOSITG%3E2.0.CO;2)
  • Lindstrom, S. S., and D. R. Watts. Vertical motion in the Gulf Stream near 68W. J. Phys. Oceanogr., 24:2321–2333, 1994. (doi:10.1175/1520-0485(1994)024%3C2321:VMITGS%3E2.0.CO;2)
  • Lindstrom, S. S., X. Qian, and D. R. Watts. Vertical motion in the Gulf Stream and its relation to meanders. J. Geophys. Res., 102(C4):8485–8503, 1997. (doi:10.1029/96JC03498)
  • Qian, X., and D. R. Watts. The SYNOP experiment: Bottom pressure maps from the central array May 1988 to August 1990. GSO Technical Report 92-3, University of Rhode Island, 1992. 187 pp.(PDF)
  • Qian, X., K. Tracey, E. Fields, and D. R. Watts. The SYNOP experiment: Inverted echo sounder data report for October 1987 to May 1988. GSO Technical Report 90-3, University of Rhode Island, 1990. (PDF)
  • Park, J.-H., and D. R. Watts. Near 5-day nonisostatic response of the Atlantic Ocean to atmospheric surface pressure deduced from sub-surface and bottom pressure measurements. Geophys. Res. Lett., 33(L12610), 2006. (doi:10.1029/2006GL026304)
  • Savidge, D. K., and J. M. Bane. Cyclogenesis in the deep ocean beneath the Gulf Stream: 1. Description. J. Geophys. Res., 104(C8):18,111–18,126, 1999. (doi:10.1029/1999JC900132 )
  • Savidge, D. K., and J. M. Bane. Cyclogenesis in the deep ocean beneath the Gulf Stream: 2. Dynamics. J. Geophys. Res., 104(C8):18,127–18,140, 1999. (doi:10.1029/1999JC900131)
  • Shay, T. J., J. M. Bane, D. R. Watts, and K. L. Tracey. Gulf Stream flow field and events near 68W. J. Geophys. Res., 100(C11):22,565–22,589, 1995. (doi:10.1029/95JC02685)
  • Watts, D. R., K. L. Tracey, J. M. Bane, and T. J. Shay. Gulf Stream path and thermocline structure near 74W and 68W. J. Geophys. Res., 100(C9):18,291–18,312, 1995. (doi:10.1029/95JC01850)
  • Watts, D. R., X. Qian, and K. L. Tracey. Mapping abyssal current and pressure fields under the meandering Gulf Stream. J. Atmos.eOceanic Technol., 18:1052–1067, 2001. (doi:10.1175/1520-0426(2001)018%3C1052:MACAPF%3E2.0.CO;2)