spring tides have a greater tidal range than neap tides.
spring tides have a greater tidal range than neap tides.
which has a greater tidal range spring or neap tides?
spring tides
the most extreme tidal range occurs during spring tides, when the gravitational forces of both the moon and sun are aligned (syzygy), reinforcing each other in the same direction (new moon) or in opposite directions (full moon). during neap tides, when the moon and sun's gravitational force vectors act in quadrature (making a right angle to the earth's orbit), the difference between high and low tides is smaller. neap tides occur during the first and last quarters of the moon's phases. the largest annual tidal range can be expected around the time of the equinox if it coincides with a spring tide.
tidal range
the tidal regime at the entrance to pelorus sound is typical of new zealand coastal locations, i.e. there is a semi-diurnal tide modulated on a spring-neap cycle, generated by the superposition of m2 (lunar, semi-diurnal) and s2 (solar, semi-diurnal) tidal constituents. other tidal constituents, notably n2 (semi-diurnal, generated by the ellipticity of the moon’s orbit), introduce further modulation, meaning that the spring-neap cycle is not exactly repeated. the tidal range varies between at neap and at spring. (these values are calculated from a sea level time series, july 1997 – february 1998, at pelorus sound entrance.) the propagation of this tidal signal into pelorus sound has not been well described, but models and measurements both suggest that the tidal range within the sound is somewhat larger (by 10–20%) than at the entrance. because the sound is long, and in places narrow, the tidal currents are fairly strong.
pelorus sound