Synoptic observations of the three-dimensional structure and propagaton of Gulf Stream meanders along the Carolina continental margin
Simultaneously measured Eulerian currents and spatially extensive subsurface temperatures have provided a time series of eigth synoptic, three-dimensional views of the Gulf Stream frontal zone along the Carolina continental margin. Two large-amplitude meanders were observed to progress through the study area between Charleston and Cape Hatteras during February 1979. Each meander had a vertically coherent, skewed wave-like subsurface structure. The Eulerian velocity and temperature signatures produced by the meanders at the 250-m level over the 390-m isobath reflect this skewness. At a particular instrument, the in-phase increases in temperature and downstream velocity associated with an approaching meander crest occurred during a longer time interval than did the more rapid decreases in these quantities following the crest's passage. Typically, the downstream velocity component at this level fluctuated from about -20 cm s/sup -1/ to near 100 cm s/sup -1/, while the cross-stream component varied approximately +- 25 cm s/sup -1/ about a near-zero mean. For a particular meander, the maximum in the offshore velocity component led the downstream maximum in time in a manner typical of progressive wave motions; however, the lead time was always less than one quarter of a meander period implying that u and v were not in quadrature, as would have been the case for stable waves. The two meanders were observed downstream of the area off Charleston where a seaward deflection of the stream is often found. Subsurface temperature data from February 10, 1979, show that on that date the degree of deflection was greatest near the surface, and that almost no deflection existed within the deeper reaches of the water column.
- Research Organization:
- Marine Sciences Program and Department of Physics, University of North Carolina, Chapel Hill, North Carolina 27514
- OSTI ID:
- 5939591
- Journal Information:
- J. Geophys. Res.; (United States), Vol. 86:C7
- Country of Publication:
- United States
- Language:
- English
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Gulf stream meanders off North Carolina during winter and summer 1979
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