4.2.1 Horizontal flow velocities
Horizontal flow vectors \(\overrightarrow{v}\) at different depths are
plotted for high-amplitude (HAT ) and low-amplitude (LAT )
cycles separately (Figure 7c~f). At each measuring
station, ebb and flood \(\overrightarrow{v}\) for below-bankfull stages
are generally characterized by similar orientations, yet with opposite
directions, whereas more scattering is observed when flow depth exceeds
the overbank stage. Directions of overbank flows appear to be consistent
across different measuring stations, with flood and ebb flows directed
to the southwest and southeast, respectively. In contrast, inter-site
variability of below-bankfull flows is more marked, as\(\overrightarrow{v}\) appears to follow the orientation of the channel
axis, with \(\overrightarrow{v}\) being more variable and generally less
correlated to the channel axis orientation for near-bankfull conditions
(i.e., water depths 0.8<\(Y\)<1.2m). It is also
worthwhile noting that flow directions at any given measuring station
display little differences between HAT and LAT cycles,
both for water stages above and below the bankfull.