The comparison of a morphodynamic model results with observations is an
essential part to establish its credibility. In the past multiple model
were validated against observations for sand banks, coastlines or
estuarine environments. Some modelling have studied the marine dunes
migrations but are generally limited to a two-dimensional study. In the
present study, a three-dimensional morphodynamic model were setup on an
area where highly dynamic dunes are present. The modelling results were
analysed and compared to in-situ observations either using a 2D and a 3D
method. The vertical and horizontal differences with observations were
then assessed using the known method and, based on these results, an
updated validation method were proposed to overcome some issues that
could interfere with the process.