River Monitoring with Ground-based Videography - Fluvial Remote Sensing for Science and Management - page 364

Figure 16.5 Comparison between current meter measurements and time-averaged LSPIV estimates in the River Warfe and the St.
Charles River: a) unfiltered LSPIV data; and b) filtered PIV data.

Wharfe due to a high-suspended load. Flare effects were
observed at both sites but were more pronounced on
the St-Charles River due to the clear sky conditions
that favoured the reflection of sunlight on the water
surface.
Post filtering, the PIV measurements of both sites
showed a strong and significant relationship with cur-
rent meter measurements, with slope values approaching
one (River Wharfe, R 2

St-Charles River, R 2

02).
When combining the two data sets, a strong signifi-
cant relationship (R 2

= 0 . 92, p < 0 . 001, slope = 1 .

= 0 . 95, p < 0 . 001, slope = 0 . 94)
was obtained between current meter and PIV measured
velocities, with PIV measures showing an accuracy of
− 26 cm/s (Figure 16.5b).

These results are comparable to those obtained by Bradley
et al. (2002) who found differences between PIV and
current meter velocity measurements of less than 6 cm/s.

4 . 37 cm/s and precision of ± 5 .

= . < . = .

0 92, p 0 001, slope 0 86;