what is coastal
A coastal zone is the interface between the land and water. These zones are important because a majority of the world's population inhabit such zones. The tidal bulges result in a rhythmic rise and fall of ocean surface, which is not noticeable to someone on a boat at sea, but is magnified along the coasts. 2  Usually there are two high tides and two low tides each day, and thus a variation in sea level as the tidal bulge passes through each point on the Earth's surface.