What is tidal amplitude?

Tidal amplitude refers to the vertical distance between the highest point that the tide reaches (high tide) and the lowest point it descends to (low tide). Specifically, it measures how much the water level changes between high and low tide. This value is crucial for understanding tidal patterns, forecasting potential flooding, and studying marine ecosystems, as it influences water circulation and sediment transport.

The other options do not accurately capture the definition of tidal amplitude. For instance, temperature differences between tides or salinity variations are unrelated to the vertical height measurement that tidal amplitude represents. Similarly, the speed of water flow during tidal changes pertains more to tidal currents rather than the amplitude itself. Therefore, the correct choice is the one that directly correlates with the change in water levels associated with tides.