ocean surface wave In fluid dynamics, a wind wave, water wave, or wind-generated water wave, is a surface wave that occurs on the free surface of bodies of water as a result from the wind blowing over the water surface. The contact distance in the direction of t ...

s approach

shore A shore or a shoreline is the fringe of land at the edge of a large body of water, such as an ocean, sea, or lake. In physical oceanography, a shore is the wider fringe that is geologically modified by the action of the body of water past a ...

, they get taller and break, forming the foamy, bubbly surface called ''surf''. The region of

breaking wave In fluid dynamics, a breaking wave or breaker is a wave whose amplitude reaches a critical level at which large amounts of wave energy transform into Wave turbulence, turbulent kinetic energy. At this point, simple physical models that describ ...

s defines the surf zone, or breaker zone. After breaking in the surf zone, the waves (now reduced in height) continue to move in, and they run up onto the sloping front of the

beach A beach is a landform alongside a body of water which consists of loose particles. The particles composing a beach are typically made from rock, such as sand, gravel, shingle, pebbles, etc., or biological sources, such as mollusc shel ...

, forming an uprush of water called

swash Swash, or forewash in geography, is a turbulence, turbulent layer of water that washes up on the beach after an incoming ocean surface wave, wave has broken. The swash action can move beach materials up and down the beach, which results in the ...

. The water then runs back again as backwash. The nearshore zone where wave water comes onto the beach is the surf zone. The water in the surf zone is shallow, usually between deep; this causes the

waves Waves most often refers to: *Waves, oscillations accompanied by a transfer of energy that travel through space or mass. * Wind waves, surface waves that occur on the free surface of bodies of water. Waves may also refer to: Music * Waves (ban ...

to be unstable.

Animal life

The animals that often are found living in the surf zone are

crabs Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen) ( el, βραχύς , translit=brachys = short, / = tail), usually hidden entirely under the thorax. They live in all the ...

clams Clam is a common name for several kinds of bivalve molluscs. The word is often applied only to those that are edible and live as infauna, spending most of their lives halfway buried in the sand of the seafloor or riverbeds. Clams have two ...

, and

snails A snail is, in loose terms, a shelled gastropod. The name is most often applied to land snails, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class Gastro ...

. Surf clams and

mole crabs Hippoidea is a superfamily of decapod crustaceans known as sand crabs or mole crabs. Ecology Hippoids are adapted to burrowing into sandy beaches, a habit they share with raninid crabs, and the parallel evolution of the two groups is striking ...

are two species that stand out as inhabitants of the surf zone. Both of these animals are very fast burrowers. The surf clam, also known as the variable coquina, is a filter feeder that uses its gills to filter microalgae, tiny

zooplankton Zooplankton are the animal component of the planktonic community ("zoo" comes from the Greek word for ''animal''). Plankton are aquatic organisms that are unable to swim effectively against currents, and consequently drift or are carried along by ...

, and small particulates out of seawater. The mole crab is a suspension feeder that eats by capturing zooplankton with its antennae. All of these creatures burrow down into the sand to escape from being pulled into the ocean from the tides and waves. They also burrow themselves in the sand to protect themselves from predators. The surf zone is full of nutrients, oxygen, and sunlight which leaves the zone very productive with animal life.

Rip currents

The surf zone can contain dangerous rip currents: strong local currents which flow offshore and pose a threat to swimmers. Rip-current outlooks use the following set of qualifications: # ''Low-risk rip currents'': Wind and/or wave conditions are not expected to support the development of rip currents; however, rip currents can sometimes occur, especially in the vicinity of

jetties A jetty is a structure that projects from land out into water. A jetty may serve as a breakwater, as a walkway, or both; or, in pairs, as a means of constricting a channel. The term derives from the French word ', "thrown", signifying somet ...

and

pier image:Brighton Pier, Brighton, East Sussex, England-2Oct2011 (1).jpg, Seaside pleasure pier in Brighton, England. The first seaside piers were built in England in the early 19th century. A pier is a raised structure that rises above a body of ...

s. Know how to swim and heed the advice of lifeguards. # ''Moderate-risk rip currents'': Wind and/or wave conditions support stronger or more frequent rip currents. Only experienced surf swimmers should enter the water. # ''High-risk rip currents'': Wind and/or wave conditions support dangerous rip currents. Rip currents are life-threatening to anyone entering the surf.

References

* Pinet, Paul R (2008) ''Invitation to Oceanography'', Chapter 11: The Dynamic Shoreline. Edition 5 revised. Jones & Bartlett Learning, * "Breaker Zone." ''The Free Dictionary''. Farlex Inc, 2012. Web. 18 Apr. 2012. .

External links

* ''MetEd'' (2012
Rip currents: Nearshore fundamentals
University Corporation for Atmospheric Research. Retrieved 17 April 2012. {{DEFAULTSORT:Surf zone Coastal geography Physical oceanography Oceanographical terminology

Animal life

Rip currents

See also

References

External links