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J. M. Magalhaes et al.
Fig. 14.5 Maxima of Baines (1982) depth-integrated body force (F) over a complete tidal cycle,
calculated using Eq. (14.2) for 4 December 2009 (same date as Figs. 14.2 and 14.4). The area shown
corresponds to the black rectangle in Fig. 14.1. A reference location for the Sofala Bank is labelled
SB. The coastline is marked by a black contour and the thin lines are the 200 and 1,000 m isobaths.
A composite map of ISW observations (six in total, see text for details) propagating in MC is also
shown in grey thick lines. The inset on the bottom-right corner is a vertical profile corresponding
to the section in a black line, which goes from the region of maximum F towards the southeast,
along the ISWs propagation path. The vertical and horizontal axes are depth in meters and distance
in kilometres (measured from the northwest end). The vertical section shows a ray-tracing diagram
for the M 2 tidal constituent and assuming stratification typical for the summer in the MC. The red
star in the map represents the critical bathymetry from where IT beams are generated, and the black
square is the corresponding reemergence at the thermocline (see text for more details)
areas above 100 m, and in the deep ocean basin that extends farther away into the
MC.
The section shown by a black line in Fig. 14.5, which extends in an approximately
perpendicular direction to the shelf-edge (from the northwest to the southeast), is
representative of a vertical profile for IT ray-paths (see the inset shown in the lower
right corner). The red star marks the position of critical bathymetry along that same
profile for the M 2 tidal constituent and using the October stratification used earlier
(the same used to calculate F; see Fig. 2a in da Silva et al. 2009). The black square
is the corresponding reemergence at the thermocline. It can be seen that there are
internal tidal beams originating from critical topography coincident with elevated
regions of F that initially slope downward into the ocean interior. The IT beam then
reflects upward from the seafloor between 1,100 and 1,300 m, and reemerges later
at the thermocline at about 90 km offshore.
J. M. Magalhaes et al.
Fig. 14.5 Maxima of Baines (1982) depth-integrated body force (F) over a complete tidal cycle,
calculated using Eq. (14.2) for 4 December 2009 (same date as Figs. 14.2 and 14.4). The area shown
corresponds to the black rectangle in Fig. 14.1. A reference location for the Sofala Bank is labelled
SB. The coastline is marked by a black contour and the thin lines are the 200 and 1,000 m isobaths.
A composite map of ISW observations (six in total, see text for details) propagating in MC is also
shown in grey thick lines. The inset on the bottom-right corner is a vertical profile corresponding
to the section in a black line, which goes from the region of maximum F towards the southeast,
along the ISWs propagation path. The vertical and horizontal axes are depth in meters and distance
in kilometres (measured from the northwest end). The vertical section shows a ray-tracing diagram
for the M 2 tidal constituent and assuming stratification typical for the summer in the MC. The red
star in the map represents the critical bathymetry from where IT beams are generated, and the black
square is the corresponding reemergence at the thermocline (see text for more details)
areas above 100 m, and in the deep ocean basin that extends farther away into the
MC.
The section shown by a black line in Fig. 14.5, which extends in an approximately
perpendicular direction to the shelf-edge (from the northwest to the southeast), is
representative of a vertical profile for IT ray-paths (see the inset shown in the lower
right corner). The red star marks the position of critical bathymetry along that same
profile for the M 2 tidal constituent and using the October stratification used earlier
(the same used to calculate F; see Fig. 2a in da Silva et al. 2009). The black square
is the corresponding reemergence at the thermocline. It can be seen that there are
internal tidal beams originating from critical topography coincident with elevated
regions of F that initially slope downward into the ocean interior. The IT beam then
reflects upward from the seafloor between 1,100 and 1,300 m, and reemerges later
at the thermocline at about 90 km offshore.