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High tide Low tide

The shape of bays and estuaries, geographic location and weather patterns all can affect local tidal intensity. This image of a tidal monitoring station in Alaska taken at high and low tide illustrates the dramatic effect that geographic location can have on tidal range. At increasing lattitudes (as one moves further from the equator and closer to the poles) there often is a dramatic increase in tidal range—in this case, approximately 45 feet.