In coastal areas, tidal currents are generally dominant. The tidal model developed at HERMESS (see: http://www.hermess.nl/tidal-info/) can provide depth-averaged tidal currents and derived surface currents worldwide. These off-the-shelf products can be further refined with the help of user supplied measurements or surface current assessments based on AIS data (see: http://www.hermess.nl/tidal-surface-currents/ ).
The techniques that HERMESS have developed to assess current variations from AIS data can also be applied to improve the accuracy of ocean circulation model calculations in areas with strong spatial gradients. Examples of such phenomena are large eddies (see: http://www.hermess.nl/eddies/) and meandering coastal currents.