Wind waves at many wavelengths and heights may approach a single spot from different directions to form a(n) _____. 

Upwelling areas are _____. 

Of the six great current circuits of the world, the _____ is the largest current and technically not a gyre because it does not flow around the periphery of an ocean basin. 

The orbits of water molecules in waves moving through _____ water are flattened by the proximity of the bottom. 

Marine erosion is usually most rapid on _____ coasts. 

Chlorofluorocarbons (CFCs) can be used as _____, which are artificial substances with known histories of production or release.

Which statement describes the characteristic of the Atlantic coast? 

If a wind wave remains in water deeper than half its wavelength and the wind continues to blow, the wave becomes _____. 

A wave in which particles of water move in closed circles as the wave passes is called a(n) _____. 

The reference level to which tidal height is compared is called the_____.