Term
|
Definition
| any action that moves the water in a “different” trajectory that it is moving when initially contacted. |
|
|
Term
|
Definition
| waves at the ocean surface that move in circular orbits |
|
|
Term
|
Definition
| the highest part of a wave. |
|
|
Term
|
Definition
| the lowest part of a wave. |
|
|
Term
|
Definition
| the vertical distance between a crest and a trough |
|
|
Term
|
Definition
| the horizontal distance between any two corresponding points on successive waveforms, such as from crest to crest or from trough to trough. |
|
|
Term
|
Definition
| the ratio of wave height to wavelength. |
|
|
Term
|
Definition
| the time it takes one full wave - one wavelength – to pass a fixed position |
|
|
Term
|
Definition
| the number of wave crests passing a fixed location |
|
|
Term
|
Definition
| is equal to wavelength ÷ 2 |
|
|
Term
|
Definition
| when wave height is < ½ the water depth |
|
|
Term
|
Definition
| when water depth is less than 1/20 the wavelength |
|
|
Term
|
Definition
| the wavelengths are between 2 x and 20 x the water depth |
|
|
Term
|
Definition
| the tiny waves that are created when the wind initially interacts with water. The deformation of the ocean surface that are small, rounded waves with V-shaped troughs and wavelengths less than 1.73 cm. commonly called ripples. |
|
|
Term
|
Definition
| symmetric waves that have wavelengths exceeding 1.74 cm. |
|
|
Term
|
Definition
| the equilibrium condition that prevents waves from growing because they lose as much energy breaking as whitecaps under the force of gravity as they receive from the wind. |
|
|
Term
|
Definition
| waves that were generated in a sea area move toward its margins, wind speeds diminish and the waves eventually move faster than the wind, when this occurs, wave steepness decreases and waves become long-crested waves called swells. |
|
|
Term
|
Definition
| how the continental margins gradually get shallower |
|
|
Term
|
Definition
| a turbulent mass of air and water that runs down the front slope of the wave as it breaks. They result from a gently sloped ocean bottom, which gradually extracts energy from the wave over an extended distance and produces breakers with low overall energy. |
|
|
Term
|
Definition
| has a curling crest that moves over an air pocket. The curling crest occurs because the particles in the crest literally outrun the wave, ant there is nothing beneath them to support their motion. |
|
|
Term
|
Definition
| when the ocean bottom has an abrupt slope, the wave energy is compressed into a shorter distance, and the wave will surge forward. These waves build up and break right at the shoreline. |
|
|
Term
|
Definition
| segments of the wave that “feel bottom” first and slow before the rest of the wave. It is the bending of waves. |
|
|
Term
|
Definition
| when a wave’s energy is reflected back parallel to incoming waves (same as a mirrors reflection). |
|
|
Term
|
Definition
| (stationary waves) can be produced when waves are reflected at right angles to a barrier. They are the sum of two waves with the same wavelength moving in opposite directions, resulting in no net movement. |
|
|
Term
|
Definition
| the Japanese term for the large, sometimes destructive waves that occasionally roll into their harbors. They originate from sudden changes in the topography of the sea floor caused by such events as slippage along underwater faults, underwater avalanches such as turbidity currents or the collapse of large oceanic volcanoes, and underwater volcanic eruptions. |
|
|
Term
| Explain the development of wind-generate waves |
|
Definition
Wind generated waves are Capillary and Gravity Waves
• Capillary Waves: as the wind blows over the ocean surface, it creates pressure and stress. These factors deform the ocean surface into small, rounded waves with V-shaped trough’s and wavelengths less than 1.74 cm.
• Gravity Waves: as more energy is transferred to the ocean gravity waves develop, these are symmetric waves that have wavelengths exceeding 1.74 cm. their length is generally 15 – 35 times their height. |
|
|
Term
| Discuss the three factors affecting wave energy (wind speed, duration, & fetch): |
|
Definition
• Wind Speed: the speed of the wind – wind transfers energy to the water directly.
• Duration: the length of time during which the wind blows in one direction – this causes the waves to continually build.
• Fetch: the distance over which the wind blows in one direction – the longer the wave experiences no change the easier it is to get into phase. |
|
|
Term
| Differentiate between constructive, destructive, and mixed interference: |
|
Definition
• Constructive Interference: occurs when wave trains having the same wavelength come together in phase, meaning crest to crest and trough to trough. If the displacements from each wave are added together, the interference patter results in a wave with the same wavelength as the two overlapping wave systems but with a wave height equal to the sum of the individual wave heights.
• Destructive Interference: occurs when wave trains having the same wavelength come together out of phase, meaning the crest from one wave coincides with the trough form a second wave. If the waves have identical heights, the sum of the crest of one and the trough of another is zero, so the energies of these waves cancel each other.
• Mixed Interference: in most ocean areas, it is likely that two or more swells of different heights and lengths will come together and produce a mixture of constructive and destructive interference. |
|
|
Term
| Describe the changes to a wave as it approaches the shore: |
|
Definition
| The shoaling depths interfere with water particle movement at the base of the wave, so the wave speed decreases. As on wave slows the following waveform, which is still moving at its original speed, moves closer to the wave that is being slowed, causing a decrease in wavelength. Although some wave energy is lost due to friction, the wave energy that remains must go somewhere, so wave height increases. This increase in wave height combined with the decrease in wavelength causes and increase in wave steepness. When the wave steepness reaches the 1:7 ratio, the waves break as surf. |
|
|
Term
| Describe the changes that are observed as a tsunami approaches a coastal areas: |
|
Definition
| There is typically an abrupt vertical movement along a fault on the sea floor that raises or drops the ocean water column above a fault creating a tsunami that travels from deep to shallow water where it is experienced as alternating surges and withdrawals of water at the shore, the base length of a Tsunami makes it a shallow water wave with tremendous energy. |
|
|
Term
| Describe the Tsunami Warning System and its effectiveness: |
|
Definition
| It uses seismic waves – some of which travel through earth at speeds 15x faster than a tsunami – to forecast destructive tsunami. There is also a network of sensitive pressure sensors on the deep-ocean floor of the pacific that pick up the small yet distinctive pressure pulse from a tsunami passing above. The sensors relay information to a buoy at the surface that transmits the data via satellite, allowing oceanographers to detect the passage of a tsunami in the open ocean. |
|
|
