ECORS Truc-Vert 2008  Sandy beach hydrodynamics and morphodynamics, Truc-Vert 2008 field experiment

Exploring beach morphodynamic and hydrodynamic processes has been a challenging task for many decades. Key in improving our understanding of physical processes has been the many field experiments conducted by researchers all around the world. Field observations are a continuous and endless source to identify new processes, generate and test novel hypotheses, and ultimately improve prediction skills of nearshore evolution. Moreover, they provide the only possibility for studying hydrodynamical and sediment transport processes under natural conditions. Collecting field data remains a key objective in coastal research for many other reasons: it allows model calibration and validation, and it drives, informs and complements controlled laboratory experiments. Thanks to field experiments, much progress has been made this last decade, in understanding fluid and sediment processes in nearshore hydrodynamics. Barred beaches have received great attention in the coastal morphodynamic literature by means of short-duration (< weeks) field experiments (among many others, Thornton et al., 1996; Gallagher et al., 1998; Ruessink et al., 1998; Ruessink et al., 2001; MacMahan et al., 2005; Aagaard et al., 2005; Masselink et al., 2008, Bruneau et al., 2009), long-term (> years) observations (among others Ruessink and Kroon, 1994, Plant et al., 2001; Van Enckevort and Ruessink, 2003a, 2003b, Ranasinghe et al., 2004, Turner et al., 2007; Quartel et al., 2007, Senechal et al., 2009), numerical modelling approaches (among others Reniers et al., 2004; Garnier et al., 2006, Hsu et al., 2006; Dronen and Deigaard, 2007; Smit et al., 2008) and physical modelling approaches (e.g. Grasso et al., 2009; Castelle et al., 2009). Many studies have shown that nearshore wave transformation, circulation and bathymetric changes involve coupled processes at many spatial and temporal scales (among others Symonds and Ranansinghe, 2000; Plant et al., 2001; Feddersen et al., 2003; Coco and Murray, 2007; Ruessink et al., 2007; Thornton et al., 2007; Pape and Ruessink, 2008) thus implying the need to improve knowledge at the full spectrum of temporal and spatial scales to achieve a comprehensive view of the natural system.

Despite efforts and progresses, there is still a lack in understanding of nearshore morphodynamics in presence of a single storm and post-storm event over complex 3D morphologies but also more generally in presence of a rapid succession of storm/post-storm conditions. Most of the previous field experiments including the ones that involved the collection of comprehensive (covering several temporal and spatial scales) data set have been conducted in presence of low to high energetic waves (offshore H_mo > 5 m). Detailed observations spanning the full range of space and time-scales in presence of extreme energetic waves, meso- to macro-tidal ranges and 3D morphologies has always been an unsolved and overwhelming challenge for the nearshore community. The Truc Vert’08 field experiment was designed to fill gaps in previous field experiments by providing new observations that incorporate extreme storm waves (Hmo up to 8m), macro-tidal conditions and complex three-dimensional morphology. Considerable interest was expressed for ECORS- Truc Vert’08. Table 1 lists the 19 organizations that participated, involving more than 120 scientists, engineers, technicians, militaries and students. Table 2 lists the main topics of interest at the different temporal and spatial scales and the organizations working on them during the field experiment.

Bathymetric survey of the area, the black box represents the sensor deployment zone

ECORS Truc Vert’08 Topics