Definitions of Words Relating to the Sea :: Ocean Marine Life Aquatics Essays

Definitions of Words Relating to the Sea The Wave Machine The wave machine is a simulator that will allow you to create an ocean wave and determine its height. Most ocean waves are formed when the wind blows across the water's surface. The wave height is determined by three factors: wind speed, fetch, and duration. Wind Speed In 1805, Sir Francis Beaufort, observing the effects of wind speed upon the sea, devised the Beaufort Wind Scale. Though wind speed is not the only factor in determining wave size, the Beaufort scale remains a tool for seafarers to this day. Wind speed is measured in KNOTS. (1 knot is equal to 1.151 mph, or 1.852 kilometers per hour). Fetch Fetch measures the area of open water over which wind blows. Like wind duration, the distance waves travel has a significant impact upon their size. Fetch is measured in NAUTICAL MILES. (1 nautical mile is equal to 1.151 miles, or 1.852 kilometers). Wind Duration Wind duration reflects how long the wind has blown in the same direction. Even at slower speeds, stead winds can create higher and more powerful waves than those resulting from brief, strong gusts. Wave Types Capillary waves The smallest waves created when the wind blows acroos a smooth water surface. Friction between the air and water molecules results in the creation of these small ripples, which are less than .7 inches long. Shallow-Water Waves Wind generated waves that travel in water shallower than one-twentieth of their wavelength. Deep-Water Waves Wind generated waves that travel in water deeper than one half of their wavelength. Swell A swell is formed when waves move away from the storm or generating area and become more regular. Waves exhibit longer periods and rounded crests, creating a uniform pattern on the ocean surface. Rogue wave A rogue wave is an unusually large wave caused by combining the heights of waves that meet simultaneously.