Ezer, T., 1994: On the interaction between the Gulf Stream and the New England Seamount chain. Journal of Physical Oceanography, 24(1), 191-204.
Abstract: In the course of numerical simulations with a primitive
equation regional model of the Gulf Stream, bottom topography and the New
England Seamount Chain (NESC) in particular show significant influence
on the variability and the energetics of the Gulf Stream system. The model
is an eddy-resolving, coastal ocean model that includes thermohaline dynamics
and a second-order turbulence closure scheme to provide vertical mixing
coefficients; it is driven at the surface by observed monthly wind stress
and heat fluxes. The surface and the deep variabilities obtained from the
numerical simulations are in fair agreement with the observed variabilities
inferred, for example, from the Geosat altimetry data and from measurements
of eddy kinetic energy (EKE).
To study how the NESC affects the Gulf Stream dynamics, a control run without
the NESC (however, leaving the other topographic features such as the continental
shelf and slope intact) is compared to simulation with full bottom topography.
According to the model results, the effects of the NESC on the Gulf Stream
include southward deflection of the stream as it passes across the NESC
and the development of several quasi-stationary, nearly barotropic recirculation
cells on both sides of the Gulf Stream. Another result is an increase in
the mean kinetic energy (MKE) and a decrease in the EKE in most of the
water column as a result of the inclusion of the NESC. The inclusion of
the NESC causes an upstream shift in the area of maximum variability compared
with the case without the NESC; the maximum deep EKE is thus obtained upstream
of the NESC. This study suggests that the stabilizing effects of the bottom
topography dominate over possible destabilizing effects due to increase
in meander amplitudes near the NESC. This study also suggests that the
NESC causes a downstream decrease in the propagation speed of meanders
upstream of the NESC and the development of an almost steady, large meander
downstream of the NESC.