Figure 1 Ebb surface current pattern (upper panel) measured with the SeaSonde HF radar, (centre panel) modelled and (lower 
panel) modelled with data assimilation. 
0.75 ensures that the modelled field in (10) always exerts the assimilated field. The observed currents are assimilated 
some influence on the final estimate at each grid point; since into the circulation model by applying equation (10) to each 
the modelled fields are spatially smoother than the SeaSonde hourly measurement, without time nudging. 
measurements, this weight provides some smoothing of noise 
430 Intemational Archives of Photogrammetry and Remote Sensing. Vol. XXXII, Part 7, Budapest, 1998