Why are there no tides in the Mediterranean Sea?
All the tides we experience on Earth are generated in the Great Oceans as a result of their response to the tide raising forces generated by the gravitational attraction between the Earth, the Moon and the Sun. If the natural resonance period of the body of water matches the frequency of the tide raising forces then it will respond accordingly and a tide is generated. For example, the Atlantic has a natural period of resonance in the order of 12.5 hours and so responds vigorously to the twice daily (semi-diurnal) tide raising forces. The Pacific on the other hand has a natural period of resonance closer to 25 hours and so responds vigorously to the daily (diurnal) tide raising forces. There are, of course, exceptions to both in unique locations in either ocean but to understand why you would need to consult any authoritative textbook on tidal theory.
