Indicators of nearshore dynamics
Information for proper data use
Bathymetry
Definition
Evolution
Digital Elevation Models in depthsx
Mapping of vertical differentials from date to date
Suitable for evaluating seasonal to longer-term sediment balance.
Not suitable for fine calibration of sand replenishment and dredging.
Isobaths extracted from bathymetry can provide simplified information that is easier to read in the case of complex bathymetry. Otherwise, opt for the “Sandbar position » indicator which provides an indication of the active littoral drift zone and the main sedimentary displacements.
Sandbars position
Definition
Evolution
Spectral signal associated to the crest of a sandbar or the position of the wave breaking (proxy close to the top of the bar).
Distance from coastline to sandbar along perpendicular transects
Suitable for assessing the dynamics of sedimentary stocks in front of sandy beaches, for defining the dynamics during the stormy seasons
Consider the natural known dynamics, adjust the monitoring frequency.
To be coupled with coastline dynamics for any interpretation of sediment budgets. Requires good thematic knowledge
For the conditions listed that are not suitable for this indicator, opt for the “bathymetry” indicator.