Waves

3 Types of Breaking Waves 1. Plunging Breakers 2. Spilling Breakers 3. Surging Breakers

1. Plunging Breakers This type of breaking wave forms where there is a moderately steep, sloping bottom. These waves form tubes or curls that move in a circular motion downward into the trough of the wave and break with a forceful crash.

2. Spilling Breaker This type of wave forms where the bottom of the ocean slopes gradually. “Spillers” move toward the shore with a line of foam tumbling steadily down their front. These waves break slowly over a long distance.

3. Surging Breakers These types of waves form when large waves suddenly hit bottom in shallow water. Examples: Hurricane Tidal Surge, Tsunami waves and tidal bores. These waves can cause great damage when they run up on the beach.

Parts of a Wave Still Water Level: Water level when surface is smooth and flat with no waves Crest: The highest point of a wave Trough: The lowest point of a wave Wave height (H): The vertical distance from crest to trough

Wavelength Wavelength (L): The horizontal distance from crest to crest. (L=meters/wave)

Wave Period Wave period (T): The time in seconds that it takes for one complete wave (from crest to crest) to pass a fixed point. (T=waves/second)

Wave Frequency Wave Frequency (F): The number of wave crests that pass a fixed point per unit of time, usually in seconds (F=waves/seconds)

Wave Speed Wave Speed (C): The speed of the wave in a certain direction expressed as distance per unit of time (C=distance/time)

Wind Waves Winds are the primary source of energy for waves. When wind begins to blow it creates ripples on the surface of the water and as the wind continues to blow those ripples turn into waves.

Wind Waves Most ocean waves are produced by the force of the wind: Force of wind is influenced by: 1. Duration: length of time wind blows 2. Fetch: the distance over which the wind blows 3. Speed: the speed over the fetch

Sea States Ripples: small wavelets averaging about 8 cm high Chop: state where winds push ripples enough to make them into waves that are about 1 meter high. Storm Waves: Gale-force winds (more than 70 km/hr), waves can reach 14 meters or higher Hurricanes Typhoons Tropical Cyclones Sea: confused mixture of waves, can include all other types of waves Swells: waves that have traveled beyond where they were generated, do not need wind to push them further

Coastlines and Islands

The 5 Wave Patterns 1. Converging : Higher waves form when the crest of two waves come together 2. Diffracting: Wave crests that spread out over duration, decreasing in height and intensity 3. Parallel: Sets of waves traveling together in the same direction with crests that are equally distant from one another 4. Radiating: Sets of waves that move outward in concentric rings from one source 5. Reflecting: Waves that have bounced off an object