Oceans for Printing

8/11/2019 Oceans for Printing

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OCEANS

Salinityis the amount of salt found in 1 kg of water Salinity or salt content, is written in parts per thousand (ppt) because there are 1000 g in 1 kg.The average ocean salinity is 35 pptIt is said that the Black Sea is so diluted by river runoff, its average salinity is commonly around 1 pptFresh water salinity is usually less than 0.5 t!ater between 0.5 t and 1" t is called !rackish

"hree vertical layers o# ocean salinity$

1. Sur#ace layer # has a mi$ed salinity de ending on rainfall or runoff from the land%. %iddle layer # is called halocline with a medium range of salinity&. &eepest and coldest # ocean water has the highest level of salinity

"e'peratureThe ocean has a broad tem erature range from warm '&( 0)* shallow coastal waters of the e+uator to thenearly free ing arctic watersThe free ing oint of seawater is about %0), instead of the 0 0) free ing oint of ordinary water

-s seawater increases 5 t in salinity, the free ing oint decreases by 1".50

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"hree vertical te'perature ones o# the ocean$

1. Sur#ace layer or 'i ed layer # this warmest layer is affected by wind, rain, and solar heat%. Thermocline layer # here the water tem erature dro s as the de th increases, since the

sun s enetration dro s too&. &eep*+ater layer # water tem erature in tis one sinks slowly as de th increases

# the dee est arts of the ocean are around % 0) in tem erature

&ensity Tem erature, salinity, and ressure come together to influence water density # which is the weight of water

divided by its volume)old seawater is denser than warm coastal water and will sink below the less dense layer

"e'perature salinity , density

"hree density ones o# ocean +aters$

1. Sur#ace layer # form by less dense water # the tem erature and salinity of layer varies according to its contact with the air # for e$am le, when water eva orates, the salinity goes u# if a cold north wind blows in, the tem erature di s and that also affects density

%. -ycnocline or transition one # middle layer # this transition one is a barrier between the surface one and the bottom

layer, allowing little to no water movement between t he two ones&. &eep one # bottom layer, where the water stays cold and dense

-ressure -ir ushes us at a constant ressure -t sea level , this ressure is 1./0 pounds per s uare inch (psi) or 1 kg2c'/n the to of the mountain, the ressure is less!ater is a lot heavier than air The ushing force ' ressure* goes u when you enter the water In fact, at 10 m in de th, one atmos here '1 ." si* ushes down on you

Acoustics

!ater is a great sound conductor It doesn t absorb sound, but allows it to travel great distances before it fades away"he speed o# sound through the +ater is 1.54 * 1504 '2sThe travel time increases as the water tem erature increases

ol hins and whales use a method called echolocation2y emitting a series of clicks and whistles and then listening for the echoes of the sounds bouncing off ob3ects,they can tell where things are2y echolocation, they can tell the si e, distance, and direction of ob3ects in their ath

Echolocation # is the method used by whales and dol hins to find out what is ha ening in the ocean around



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them

Sonar # is also used by oceanogra hers to study the ocean floor # it works a lot like echolocation

/ceanogra hers discovered one art of the ocean that has different and better acoustics than other arts ofthe ocean.It is known as the SO A6 channel7 +hich is short #or sonic #i ing and ranging channel

In the S/F-4 channel, low fre+uency sounds can travel for hundreds of kilometers very well

OpticsSunlight is the energy and heat source for the ocean s food chain

"hree vertical regions o# ocean +aters !ased on the a'ount o# sunlight that penetr ates1. Euphotic one # starts at the water s surface and di s downward to about 50 m in de th

# this de ends on the time of year, the time of day, the water s trans arency, and whether ornot it is a cloudy day

# this is the ocean region where there is still enough light to allow lants to carry onhotosynthesis

# all lankton, kel forests, and sea grass beds are found in the eu hotic one%. &ysphotic one # which reaches from arouns 50 m, or the edge of the eu hotic one, to about

1000 m in de th# in this one, there is enough light for an organism to see, but it is too dim for

hotosynthesis to take lace&. Aphotic one # there is no light

# e$tends from about 1000 m of de th or the lower edge of the dys hotic one to the seafloor

8n 1900 , geologists who had been e$ loring ocean fractures discovered booming thermal volcanic ventcommunities living without sunlight on the barren sea floor This big, alien#looking creatures used a reviously unknown energy rocess that doesn t include solar heatScientist discovered that the food chain de ends on sulfur for energy, not sunlight in vent communities

ee ocean bacteria transform the chemicals they get from this high#sulfur environment to energyThis energy transformation rocess is called che'osynthesis/ther dark living animals eat bacteria, shelter bacteria in their bodies or consume bacteria#eaters in the chain:ent +or's #or e a'ple have no 'outh or digestive tract/ 8nstead7 they 'aintain a sy'!ioticrelationship +ith these che'osynthetic !acteriaThe bacteria live in their tissues and rovide them with foodStranger still, scientists #ound that he'oglo!in +hich transports hydrogen sul#ide to the !acteria7 givesvent +or's a red color

Black s'okers # the hottest dee ocean hot s rings, have been known to reach tem eratures of&(0 0)

;hite s'okers # have a different com osition and lower tem eratures

Biolu'inescenceSome animals in the a hotic one create their own light through a chemical reaction. "his is called!iolu'inescence/These microsco ic organisms, floating on the surface, roduce their own light through bioluminescence

isturbances by boats, shi s, and swimmers can all cause these organisms to glow

Ocean 6egionsThe dee ocean basin, located at the de th of about &." # 5.6 km dee , covers &07 of earth s surface and hassuch features as, abyssal lains, dee #sea trenches, and seamounts

A!yssal plain # is the flat, dee ocean floor # it is almost featureless because a thick layer of sediment covers the hills and valleys of the

ocean floor below it# dee sea trenches are the dee est arts of the ocean

Shorelines!aves, various currents, and tides all intermingle with s ecific land, rocks, and lates to give shorelines uni+uecharacteristics

"he 'ain #actors that a##ect the creation and 'aintenance o# the shorelines all around the +orld include$1. 4ising of coastal area with associated erosion%. Sinking of coastal areas with sediment de osition&. Ty es of rocks or sediments resent



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. )hanges in sea level5. )ommon and storm wave heights6. 8eights of tides affecting erosion and sedimentationBeaches are generally co'posed o# three parts$

1. Backshore # e$tend from the dunes or land margin to the surf %. oreshore # is the area with the most wave action

# this includes the high and low tide areas of the beach

&. O##shore # e$tends from where the ocean bottom is shallow enough for waves to break, all theway out into the ocean de ths

<ittoralThe littoral one # is a tidal de th gradient found closest to the shoreThe littoral area is also where marine life, like 3elly fish, is foundThe littoral one reaches from the shoreline to nearly %00 m out into the o en ocean

<ittoral one is divided into three overlapping sections$

1. Supralittoral one * or spray one is only washed over during very high tides or during bigstorms

%. 8ntertidal one # is found between the high#tide and low#tide lines&. Su!littoral one # e$tends from the low#tide line out to %00 m in the water

Currents

"he seven 'ain currents include$1. -ntarctic )ircum olar current 'also called the !est !ind rift*%. 9ast !ind rift&. :orth 9+uatorial current

. South 9+uatorial current5. ;eru current6. <uroshio current". =ulf Stream

These currents move in large rotatng circles called gyres .=yres form when the main ocean currents intersect;ater #lo+s in a circular path$ clock+ise in the northern he'isphere and counterclock+ise in thesouthern he'isphere

"+o o# the largest currents$

1. -ntarctic circum olar current%. <uroshio current

Cali#ornia current # is an eastern boundary current# it is wide, leisurely, cool, and shallow

So'ali current # of -frica s eastern coast, is a current with a twist# it does the im ossible, it reverses direction twice a year #from >ay to Se tember, the Somali current runs northward# from :ovember through >arch it runs southward

=ul# Strea' # surface current is strong, western boundary current# it is warm, dee , swift, and fairly salty, se arating o en ocean water from coastal water # commonly travels at a s eed of nearly knots# it is a art of a greater current system that includes the :orth -tlantic )urrent, )anary)urrent, and the :orth e+uatorial )urrent

Coastal Currents!hen waves hit the beach at an angle, it is called a <ongshore current6ip currents or rip tides are a dangerous side effect of ?ongshore currents

6ip tides or 6ip Currents # are caused by a combination of ?ongshore currents and underwaterfeatures that react with the current

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Oceans for Printing