Tidal range
Topic: Movements of Ocean Water: Waves, Tides and Currents · NCERT: Class 11, Ch 13 "Movements of Ocean Water"
Meaning
Tidal range is the difference in height between high tide and low tide. It changes from place to place and from time to time. It is large over wide continental shelves and in funnel-shaped bays, and small at mid-ocean islands. It is also larger at spring tides (Sun, Moon and Earth in a line), at perigee (Moon closest to Earth) and at perihelion (Earth closest to the Sun). It is smaller at neap tides, apogee and aphelion.
Example
The Gulf of Khambhat in Gujarat has the largest tidal range in India, with the Gulf of Kachchh next. This makes both sites suited to tidal power. The world's largest range is in the Bay of Fundy, Canada, at about 15–16 m.
Don't confuse with
- Wave height: the height of a wind-driven wave from trough to crest. Tidal range is the slow rise and fall of the whole sea level over hours.