TY - JOUR
T1 - A model study of "bump" induced western boundary current variabilities
AU - Oey, Lie Yauw
AU - Ezer, Tal
AU - Mellor, George L.
AU - Chen, Ping
N1 - Funding Information:
The support by the National Science Foundation under grant no. OCE-8711614 (LYO and PC), and by the Institute for Naval Oceanography, under contract no. INO-$8751 (LYO, TE and GLM), are gratefully acknowledged. Computer support was provided by the National Center for Supercomputing Applications, Illinois, the Pittsburgh Supercomputer Center and the Geophysical Fluid Dynamics Laboratory of NOAA, Princeton.
PY - 1992/8
Y1 - 1992/8
N2 - A time-dependent, three-dimensional numerical model is used to study the effects of a bottom irregularity or "bump" on western boundary current (WBC) variabilities along a simplified shelf and slope. Numerical experiments with (i) no bottom bump, (ii) a small bump and (iii) a large bump have been conducted. Case (i) produces low variabilities and cases (ii) and (iii) show significant increase in slope and shelf energetics both downstream and upstream of the bump. Disturbances generated at the bump are well correlated with flow variabilities upstream. Downstream variabilities are caused by meander development following the WBC deflection by the bump, while topographic waves excite upstream variabilities. The model also indicates two modes of deflection paths, small- and large-amplitude pahs, downstream of the bump. These findings are further supported by results obtained from a Gulf Stream simulation which incorporates the bathymetry of the U.S. South Atlantic Bight, and which has a more realistic boundary forcing. The simulated eddy kinetic energy distribution shows three regions of variability which are of interest: one inshore (and slightly downstream) and one offshore of the Charleston Bump, and a third region over the shelfbreak some 150-200 km upstream of the Bump. The inshore and offshore maxima are due to the small and large amplitude deflection paths of the model Gulf Stream, respectively, while the upstream maximum is presumably due to topographic wave activity.
AB - A time-dependent, three-dimensional numerical model is used to study the effects of a bottom irregularity or "bump" on western boundary current (WBC) variabilities along a simplified shelf and slope. Numerical experiments with (i) no bottom bump, (ii) a small bump and (iii) a large bump have been conducted. Case (i) produces low variabilities and cases (ii) and (iii) show significant increase in slope and shelf energetics both downstream and upstream of the bump. Disturbances generated at the bump are well correlated with flow variabilities upstream. Downstream variabilities are caused by meander development following the WBC deflection by the bump, while topographic waves excite upstream variabilities. The model also indicates two modes of deflection paths, small- and large-amplitude pahs, downstream of the bump. These findings are further supported by results obtained from a Gulf Stream simulation which incorporates the bathymetry of the U.S. South Atlantic Bight, and which has a more realistic boundary forcing. The simulated eddy kinetic energy distribution shows three regions of variability which are of interest: one inshore (and slightly downstream) and one offshore of the Charleston Bump, and a third region over the shelfbreak some 150-200 km upstream of the Bump. The inshore and offshore maxima are due to the small and large amplitude deflection paths of the model Gulf Stream, respectively, while the upstream maximum is presumably due to topographic wave activity.
UR - http://www.scopus.com/inward/record.url?scp=0027045240&partnerID=8YFLogxK
U2 - 10.1016/0924-7963(92)90009-W
DO - 10.1016/0924-7963(92)90009-W
M3 - 期刊論文
AN - SCOPUS:0027045240
SN - 0924-7963
VL - 3
SP - 321
EP - 342
JO - Journal of Marine Systems
JF - Journal of Marine Systems
IS - 4-5
ER -