A daily tidal range of minimal amplitude that occurs when the moon and sun are positioned at 90 degrees to one another. In this moon-earth-sun configuration, the gravitational attraction of the moon and sun compete for Earth’s water. Occurs at the first and third quarters of the moon. Tide of decreased range occurring about every 2 weeks when the moon is in quadrature, that is, during its first and last quarter. Also known as neaps, see spring tide for contrast.
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