Tidal Level Predictions in Reference to Their Datum, Based on Particular, Selective Sources

The article presents differences between tidal datum of predictions taken from six official data sources (British, American and Caribbean comprising both paper and electronic form) for three pairs of ports located on the Atlantic coast of North, Central and South America. Two day of predictions represent spring and neap tide. It can be treated as a continuation, a deeper stage of works focused on tidal comparisons. The most essential trial of tidal datum unification for particular ports gives the more adequate base for comparison of Height Deviations from reference values (for particular ports: local or mean) and shows wide variety of the results.