At the Royal NIOZ and IOW, as part of the Dutch-German NWO/BMBF PACE project, 3D high resolution numerical simulations of the hydrodynamics of the Dutch Wadden Sea were carried out. As a by-product of these simulations, we have created a three-year long (2009-2011) hindcast database of the hydrodynamic conditions of the Dutch Wadden Sea with a resolution of 200m for further usage in, especially, ecological studies. The data includes monthly averages of salinity, temperature, maximum velocity both at the bottom and the surface. In addition, the files contain the exposure time of tidal flats. 

-- The files lay_eco.YYYYMM.nc (where YYYY is the year, and MM the month) contain monthly averages of certain hydrodynamic quantities in the Dutch Wadden Sea as obtained from numerical simulations using the setup described in:

M. Duran-Matute, et al. (2014): Residual circulation and freshwater transport in the Dutch Wadden Sea: a numerical modelling study. Ocean Science, 10, 611-632.
www.ocean-sci.net/10/611/2014

Please cite this work if the data is used.

-- The files lay_eco.YYYYMM.nc are in netCDF format. The data from these files can be easily exported into MATLAB, python, or R. In fact, there are two scripts: plot_eco_av.py (for python) and plot_eco_av.R (for R), to plot the data. 

-- The variables included are
	- lat (latitude of the grid points)
	- lon (longitude of the grid points)
	- salt_bott (salinity close to the bottom)
	- salt_surf (salinity at the surface)
	- temp_bott (temperature close to the bottom)
	- temp_surf (temperature at the surface)
	- vmax_bott (maximum velocity in the bottom layer)
	- vmax_surf (maximum velocity at the surface)
	- time_expo (exposure time of the tidal flats)

-- The variable time_expo (exposure time) needs further explanation. GETM (the model used for the simulations) has a 'thin layer' drying and flooding algorithm. This means that every cell has always at least a thin layer of water with depth D_min. In these particular simulations D_min=0.1 m. We define as dry, all cell that have a depth H<0.2 m. We have done some testing. It seems that this is a good assumption, and the results are not too sensitive to the choice of the threshold. Nonetheless, there is an ongoing project to further analyze the accuracy of the obtained exposure time by comparing with remote sensing data.