The rise or fall from one high water to the next low, or the reverse. Summary versions include the mean range (mean high water minus mean low water), the great diurnal range (MHHW minus MLLW) and the spring range. Ranges vary from a few centimetres in the Mediterranean to around 16 m in the Bay of Fundy, and range ratios between stations are the basis of subordinate predictions and tide zoning.
Mean range is 3.1 metres here against 1.9 at the reference station, so apply a ratio of 1.6.
Also heard as
- range
- range of tide
Related terms
Spring tide
A tide of larger than average range, occurring around new and full moon when Sun and Moon pull in line.
Neap tide
A tide of smaller than average range, occurring near first and last quarter moon when Sun and Moon pull at right angles.
Corange line
A line joining places that share the same tidal range or the same constituent amplitude.
Subordinate station
A location whose tides are predicted by applying time and height corrections to a nearby reference station.