Shoreline

The shore zone can be divided into the coast, the shore and the offshore (Fig. 3.35). The coast has been defined as the land immediateiy behind the cliffs, whereas the shore is regarded as that area between the base of the cliffs and low-water mark. That area that extends seawards from the low-water mark is termed the offshore. The shore itself is further divided into foreshore and backshore, the former embracing the intertidai zone, whiie the latter extends from the foreshore to the cliffs. 

When wind blows across the surface of deep water, it causes an orbitai motion of the water particles in the plane, normal to the wind direction. Because adjacent particies are at different stages of their circular course, a wave is produced. The motion is transmitted to the water beneath the surface, but the orbitais are rapidiy reduced in size with increasing depth, and the motion dies out at a depth equal to that of the wavelength (Fig. 3.36). There is no progressive forward motion of the water particles in such a wave, although the form of the wave profile moves rapidly in the direction in which the wind is blowing. Such waves are described as oscillatory waves. 

The parameters of a wave are the wavelength, L, that is, the horizontal distance between each crest or each trough, the wave height, H, the vertical distance between the crest and 

Orbital motion of water particles during the passage of an idealized sinusoidal wave in deep water. The orbital diameter decreases with depth and disappears at a depth of approximately one half the wave length. 

Those waves that are developed in storm centres in the centre of an ocean may journey to its limits. This explains why large waves may occur along a coast during fine weather. 

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Bioremediation by the addition of oil-degrading microbes has been promoted as a treatment option for oked shorelines, but this approach has not yet met with any documented success (13). 

Bioremediation also offers options for dealing with oked material, such as seaweed, that gets stranded on shorelines composting has been shown to be effective. 

A buoyant spherical particle of diameter D floating in a Hquid which has no tendency to wet, ie, pull the shoreline up, or to reject, ie, push the shoreline down, the soHd submerges to a depth d at which the downward force of gravity on the sphere equals the upward buoyancy force of the displaced Hquid. This occurs when... 

Fig. 6. Approaches to minimising entrapment and impingement of fish and large aquatic invertebrates, eg, blue crabs, on trash screens at intakes, (a) An inlet pump house with vertical traveling screens mounted flush with a river shoreline to minimise obstmctions to animal movements (b) parallel flow to direct fish to a recovery chamber that returns to the water body (c) a velocity cap atop a vertical, offshore inlet induces a horizontal flow which fish avoid...

At what time of day and under what meteorological conditions is maximum ground-level pollution likely to occur at locations several kilometers inland from a shoreline industrial complex whose pollutants are released primarily from stacks of moderate height (about 40-130 m) ... 

The Offshore and Coastal Dispersion (OCD) model (26) was developed to simulate plume dispersion and transport from offshore point sources to receptors on land or water. The model estimates the overwater dispersion by use of wind fluctuation statistics in the horizontal and the vertical measured at the overwater point of release. Lacking these measurements the model can make overwater estimates of dispersion using the temperature difference between water and air. Changes taking place in the dispersion are considered at the shoreline and at any points where elevated terrain is encountered. 

Shoreline Fumigation - For rural sources within 3000 m of a large body of water, maximum shoreline fumigation concentrations can be estimated by SCREEN. A stable onshore flow is assumed with stability class F (A0/AZ = 0.035 K/m) and stack height wind speed of 2.5 m/s. Similar to the inversion break-up fumigation case, the maximum ground-level shoreline fumigation concentration is assumed to occur where the top of the stable... 

As with the inversion break-up case, the distance to maximum ground-level concentration is determined by iteration. The equation used for the shoreline fumigation case is ... 

Xj = shortest distance from source to shoreline (m) hj = plume centerline height (m)... 

Plume height is based on the assumed F stability and 2.5 m/s wind speed, and the dispersion parameter (o, ) incorporates the effects of buoyancy induced dispersion. If x , is less than 200 m, then no shoreline fumigation calculation is made, since the plume may still be influenced by transitional rise and its interaction with the TIBL is more difficult to model. 

The maximum ground-level concentration due to shoreline fumigation, Xf. is calculated from ... 

Seine net A net designed to collect aquatic organisms inhabiting natural waters from the shoreline to 3 depths is called a seine net. Most often a plankton seine. Selvage A loom finished edge that prevents cloth unravelling. 

Effects of Large Local Water Bodies. The siting of a stack along the shoreline of a large lake or along an ocean front may be accompanied by unique air... 

The Shoreline Dispersion Model (SDM) is a multipoint Gaussian dispersion model tliat can be used to determine ground-level concentrations from tall stationary point source emissions netir a shoreline emaromnent. SDM is used in conjunction witli MPTER algoritlnns to calculate concentrations when fumigation conditions do not exist. 

Shoreline, Ed 2. Pacific Tropical Botanical Garden, Honolulu. 

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