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.
wave to form, the surging tide must meet an obstacle. When the ocean meets the
walking across them. The lines and pulleys and some parts of the waves are example of
The aircrafts equipment will record the speed of the wave and the travel time during air to calculate depth . Therefore LADS must be flown during hours of darkness to eliminate the errors caused by the reflection of the sun off the water, which return false reading to the aircraft causing inaccurate depth.
Hurricanes form over the ocean. Easterly waves, what hurricanes develop from, are long, narrow regions of low pressure which occur in ocean winds called trade winds. At first, these easterly waves can grow into something called, a tropical depression. A tropical depression occurs when winds are up to 31 mph. Then tropical depressions can be upgraded into a tropical storm if the winds reach speeds of 74 mph or less. Then finally a the storm can be bumped up into a hurricane if the winds reach 75 mph.
The Sun’s radiation heats the upper atmosphere, sending the energy toward the earth’s surface and finally mixes with the planet’s counter-rotational currents, creating jetstream flows. The winds flow over the ocean’s surface creating friction that spawns chops, pushing up the seas forming perfect bands of open ocean swell. Pushed on by gravitational forces, the swells speed away from the winds that they came from, moving across the deeps until they feel the drag of the shallows near the coast. As the swells rise up out of themselves, they peak, curling into the liquid dreams that we surfers ride (Kampton 4).
In seismology, there are several types of waves studied, each of these waves have characteristics that define them. Seismic waves can be split into two categories, and they are body waves and surface waves. Body waves travel and move within the earths subsurface and inner layers. There are two types of body waves, P-Waves also known as compressional waves or primary waves, and S-Waves also called secondary or shear waves. The S-Waves have a vertical (Sv) and horizontal (Sh) component. “In an infinite homogenous isotropic medium, only P and S waves exist” (Telford et. al, 1990). On the other hand, as indicated by the name, surface waves travel and move along the surface of the earth. In general, surface waves have a lower frequency than body waves, therefore, they can easily be distinguished from body waves on a seismogram. There are two types of surface waves, Love waves and Rayleigh Waves. Love waves is the fastest surface wave, its movement mainly consists of a side to side completely horizontal motion. Rayleigh (1885) waves are surface waves that “roll” along the ground; they are a consequence of interfering P and Sv-Waves. Our project
many wave energy devices have been invented, only a small proportion have been tested and evaluated.in ocean waves, rather than in artificial wave tanks.
The wave height is the vertical distance, usually in feet, between the the trough and the crests. The wavelength is the length in feet between adjacent crests. This is one way to measure the size of waves. Another good way to measure the size of waves is by how many people get sick. More than two people means the waves are big.
Rough waves are an open water phenomenon, in which winds, currents, nonlinear phenomena cause a wave to briefly form that is far larger than the "average" large occurring wave of that time and place. rogue waves can form in large bodies of freshwater as well as the ocean. The first rogue wave confirmed with scientific evidence,it has a maximum height of 25.6 metres (84 ft).rogue waves can also reach up to about 30 meters or 100 feet high. A rogue wave estimated at 18.3 meters (60 feet) in the Gulf Stream off of Charleston, S.C.
“...Waves are a disturbances that propagate energy through a medium” (Staroscik). One example of waves in these types of submarines is for sonar. Sonar works by emitting periodic sound waves through the water. The waves bounce off objects in the water back to
waves. The waves at the front of the boat are compressed and are shorter than the longer, spread out waves at the back of the boat.
There are three major properties you must know when understanding waves. The first major property is wavelength. Wavelength is the distance between two points on a wave. The next major property is amplitude. Amplitude is measured by the height of the wave. The higher the wave, the stronger the signal of the wave is. The final property you must know is frequency. Frequency is the amount of times a wavelength transpires in a second. Frequency is measured in kilohertz but it is commonly interpreted as pitch. A high pitch requires a high frequency as does a low pitch require a low frequency.
Bathymetry is a study of underwater depth which can map large or small scale bodies of water. It is one way to measure, manage and explore water bodies. Earliest bathymetric systems used premeasured anchors or ropes to measure the depth of water on a single point of time. Bathymetry, until now has been used for a wide range of applications such as feature extraction, coastal mapping, road map guide for sea navigators, monitor erosions, monitor water rise, and classify the behavior of the community under water. For more than 50 years of development, bathymetry is done with the help of acoustic technology, namely Sound Navigation and Ranging (SoNAR). Using the basic principle of Physics, a transducer emits high frequency sound to the body of water.