The Hycom Ocean Current data comes from the US Navy, and gets distributed by Florida University. The data update times can be unreliable because of this data flow, but is our recommended ocean current model. This model is driven by GFS atmospheric model.
The Mercator model is from the Europeans and driven by ECMWF atmospheric model.
The Tidal global model comes from TideTech. So by subscribing to PredictWind professional you get the benefits of a TideTech subscription. The TideTech Global uses the Mercator ocean currents, plus a tidal component. So in some areas you will see the tidal component not present in the other ocean current models. Having a Tidal component, the time step in the model must be every hour, so the Tidal Ocean current data is a large file. We also make available the TideTech high resolution tidal models for the English Channel, North Sea, Baltic Sea, San Francisco, Tampa, New York, Sydney, Mallaca Straits and Bass Strait.