Page 77 - (DK) Ocean - The Definitive Visual Guide

WAVES AND TIDES are two important
physical phenomena that affect every area

of the oceans but tend to be most

noticeable, and have their main effects, on
or near coasts. Ocean waves are mostly

wind-generated and vary from tiny coastal

ripples, to the regular, rolling swell of the

open ocean, to monster breakers on world-

famous surfing beaches. All waves transmit
energy—when the waves reach land, this

energy may be dissipated destructively,

eroding coastlines, or constructively,
building up features such as beaches. Tides

are caused mainly by interactions between

the Moon and Earth. As well as regular

rises and falls in sea level, they can cause

strong currents around coasts and, in some
places, even more dramatic phenomena

such as whirlpools and eddies.

WAVES AND TIDES

LAPPING WAVES
Waves lapping on the seashore meet a rocky
stream at low tide near Kipahulu on the
southeast coast of the Hawaiian island of
Maui, in the Pacific.