wang_ebersole_smith_johnson
Temporal and spatial variations of surf-zone currents and suspended sediment concentration
Introduction - wang_ebersole_smith_johnson0002
Fig. 1. The LSTF during the plunging case, showing the flow channels (bottom) and the instrument bridge (top) carrying the current meters and wave gages (vertical rods)
Table 1. LSTF instrumentation and the sampling scheme for this study
Wave and beach conditions
Beach conditions
Fig. 3. Spectral characteristics of water-level fluctuations at different cross-shore locations for both spilling and plunging cases
Fig. 4. Initial and equilibrium beach profiles for the two wave case
Fig. 6. Setup and setdown during the spilling and plunging case
Results and discussion
Fig. 7. Spectra of the temporal variations of cross-shore current
Fig. 8. Spectra of the temporal variations of longshore current
Fig. 9. Time-series longshore current sampled at 20 Hz immediately landward of the main breaker line (at ADV6).
Temporal variations and periodicities of sediment concentration
Fig. 10. Time-series sediment concentration at four levels from the bed sampled at 16 Hz for spilling case (upper panel) and plunging case (lower panel). Numbers of centimeters referred to the sensor elevations above bed.
Fig. 11. Spectra of the temporal variations of suspended sediment concentration at the breaker line for spilling (upper panel) and plunging (lowe panel) case
Vertical and cross-shore variations of the time averaged longshore current
Fig. 12. Profiles of time-averaged longshore current at various locations across the surf zone, spilling case. Solid horizontal line indicates still water level
Fig. 13. Profiles of time-averaged longshore current at various locations across the surf zone, plunging case. Solid horizontal line indicates still water level
Vertical and cross-shore variations of time- averaged cross-shore current
Fig. 15. Profiles of time-averaged cross-shore current at various locations across the surf zone, spilling case. Solid horizontal line indicates still water level
Fig. 16. Profiles of time-averaged cross-shore current at various locations across the surf zone, plunging case. Solid horizontal line indicates still water level
Vertical and cross-shore variations of time- averaged sediment concentration
Fig. 18. Comparison of time-averaged suspended sediment concentration within 5 cm from the bed at various locations across the surf zone
Fig. 19. Root-mean-square of cross-shore current at 3 cm above bed, for the spilling and plunging cases
Fig. 20. Comparison of near-bed sediment concentration in the breaker zone between spilling (solid) and plunging case (clear)
Fig. 21. Vertical profiles of rms velocity at various cross-shore locations for both spilling and plunging cases. Numbers in the parentheses indicate the still-water depth.
Calculating sediment flux from current velocities and sediment concentrations
Longshore sediment flux
Fig. 23. Time averages of the ``shifted'' longshore flux in comparison with flux obtained from the product of time-averaged longshore current and time-averaged concentration. Legends refer to distance from the shoreline and sensor elevation.
Fig. 24. Sediment-flux profiles obtained from the product of time-averaged profiles of longshore current and sediment concentration.
Fig. 25. Comparison of sediment-flux distribution measured at the downdrift traps, integrated over depth, and calculated values
Cross-shore sediment flux
Fig. 26. Time averages of the ``shifted'' cross-shore flux in comparison with flux obtained from the product of time-averaged cross-shore current and time-averaged concentration. Legends refer to distance from the shoreline and sensor elevation
Concluding summary
Acknowledgements - wang_ebersole_smith_johnson0036
References - wang_ebersole_smith_johnson0037
Temporal and spatial variations of surf-zone currents and suspended sediment concentration
Introduction - wang_ebersole_smith_johnson0002
Fig. 1. The LSTF during the plunging case, showing the flow channels (bottom) and the instrument bridge (top) carrying the current meters and wave gages (vertical rods)
Table 1. LSTF instrumentation and the sampling scheme for this study
Wave and beach conditions
Beach conditions
Fig. 3. Spectral characteristics of water-level fluctuations at different cross-shore locations for both spilling and plunging cases
Fig. 4. Initial and equilibrium beach profiles for the two wave case
Fig. 6. Setup and setdown during the spilling and plunging case
Results and discussion
Fig. 7. Spectra of the temporal variations of cross-shore current
Fig. 8. Spectra of the temporal variations of longshore current
Fig. 9. Time-series longshore current sampled at 20 Hz immediately landward of the main breaker line (at ADV6).
Temporal variations and periodicities of sediment concentration
Fig. 10. Time-series sediment concentration at four levels from the bed sampled at 16 Hz for spilling case (upper panel) and plunging case (lower panel). Numbers of centimeters referred to the sensor elevations above bed.
Fig. 11. Spectra of the temporal variations of suspended sediment concentration at the breaker line for spilling (upper panel) and plunging (lowe panel) case
Vertical and cross-shore variations of the time averaged longshore current
Fig. 12. Profiles of time-averaged longshore current at various locations across the surf zone, spilling case. Solid horizontal line indicates still water level
Fig. 13. Profiles of time-averaged longshore current at various locations across the surf zone, plunging case. Solid horizontal line indicates still water level
Vertical and cross-shore variations of time- averaged cross-shore current
Fig. 15. Profiles of time-averaged cross-shore current at various locations across the surf zone, spilling case. Solid horizontal line indicates still water level
Fig. 16. Profiles of time-averaged cross-shore current at various locations across the surf zone, plunging case. Solid horizontal line indicates still water level
Vertical and cross-shore variations of time- averaged sediment concentration
Fig. 18. Comparison of time-averaged suspended sediment concentration within 5 cm from the bed at various locations across the surf zone
Fig. 19. Root-mean-square of cross-shore current at 3 cm above bed, for the spilling and plunging cases
Fig. 20. Comparison of near-bed sediment concentration in the breaker zone between spilling (solid) and plunging case (clear)
Fig. 21. Vertical profiles of rms velocity at various cross-shore locations for both spilling and plunging cases. Numbers in the parentheses indicate the still-water depth.
Calculating sediment flux from current velocities and sediment concentrations
Longshore sediment flux
Fig. 23. Time averages of the ``shifted'' longshore flux in comparison with flux obtained from the product of time-averaged longshore current and time-averaged concentration. Legends refer to distance from the shoreline and sensor elevation.
Fig. 24. Sediment-flux profiles obtained from the product of time-averaged profiles of longshore current and sediment concentration.
Fig. 25. Comparison of sediment-flux distribution measured at the downdrift traps, integrated over depth, and calculated values
Cross-shore sediment flux
Fig. 26. Time averages of the ``shifted'' cross-shore flux in comparison with flux obtained from the product of time-averaged cross-shore current and time-averaged concentration. Legends refer to distance from the shoreline and sensor elevation
Concluding summary
Acknowledgements - wang_ebersole_smith_johnson0036
References - wang_ebersole_smith_johnson0037
