Neap tides


Tides of small range which occur approximately twice a month, when the moon and sun are out of phase around times of the first and third quarters of the Moon.


Figure: (A) View looking down upon the earth from the north pole when the moon is positioned half way between the new and full phases – the two tidal budges are out of phase and combine to produce neap tides with smaller than average tidal range; (B) a tidal curve over a 15 day period using periods of neap tides.