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In this idealised experiment, an estuarine circulation is simulated, mainly in order to demonstrate how to use tracer advection and internal pressure gradients in GOTM, but also to show the basic physical process of tidal asymmetries and its impact on SPM dynamics. The average water depth is H=15 m, the model is run for 10 days. The forcing is a M2 tide (of period 44714 s) which prescribes sinusoidal time series for the vertically averaged momentum in west-east direction with an amplitude of 1.5 m/s and an offset of 0.05 m/s directed to the west in order to simulate river run-off. The surface elevation is sinusoidal as well with an amplitude of 1 m and a phase shift of 1.5 hours compared to the velocity. A constant in time and space horizontal west-east salinity gradient of -0.0005 ppt/m is prescribed, advection of salinity is turned on. In order not to obtain negative salinities, relaxation to the initial salinity profile of 15 ppt is made. In order to avoid strong stratification near the surface, a small wind stress of 0.01027 N/m^2 is applied. A simple suspended matter equation with constant settling velocity is calculated in order to show the effect of tidal asymmetries on SPM transport. It is clearly seen that during flood SPM is mixed higher up into the water column than during ebb, an effect which has been described by Geyer 1993. For further information have a look into the GOTM documentation, in subsection 'Estuarine dynamics' of the GOTM scenarios section.