Unit 5 Ocean Notes Intro to Oceanography Date: SWBAT: Describe and diagram the features of the continental margins and ocean basins.

Transcription

1 Unit 5 Ocean Ntes Name: Intr t Oceangraphy SWBAT: Describe and diagram the features f the cntinental margins and cean basins. Oceangraphy is the study f draws n gelgy, chemistry, physics and bilgy Snar - 1. Wrks by transmitting sund waves tward the bttm f the cean; sensitive receiver intercepts the ech reflected by the bttm 2. Speed f sund 3. The depths determined frm mnitring the eches Use fr The cean flr is divided int 2 areas: 1. Cntinental Margin: a. Shallw parts f cean made f b. It is nt always bvius; it s nt the shreline c. It is the dividing line between 2. Ocean Basin a. Made f It s the area beynd the cntinental rise

2 Ocean Life and Aquaculture SWBAT: Categrize cean dwellers by mvement. Describe hw we use the cean as a fd surce. Classificatin f Marine Organisms: Marine rganisms can be classified accrding t Marine Ecsystems Sme f the mst diverse marine ecsystems are: Planktn Benths Nektn freshwater and seawater mix near surface f trpical waters frmed by skeletal depsits f cral Descriptin All rganisms (algae, animals and bacteria) that drift with the cean currents. Phytplanktn are Phytplanktn perfrm phtsynthesis. Zplanktn are free flating, Zplanktn eat phytplanktn. any frm f cean life that nekts = Animals capable f mving independently f the cean currents by Ex. Adult fish, squid, marine mammals and reptiles Fd frm the Ocean Aquaculture: Catfish, salmn, ysters, and shrimp Traditinal Land-based t cean-based cultivatin Fishing Substantial cntributins t fd supplies Destructin f castal ecsystems Sustainable Land-based t cean-based cultivatin Fishing Plant-based feeds Des nt negatively affect wildlife Supprts lng-term ecnmic and scial well-being f lcal cmmunities

3 Temperature, Salinity and Acidificatin SWBAT: Describe hw the cean temperature changes with depth; determine hw salinity affects density. Temperature the surface f cean water (H 2O) 3 temperature znes f cean water: Surface zne: ; sea level t 300m; sunlight nly penetrates a few meters, but wind and waves mix heat evenly thrughut the surface zne. Thermcline zne: marked by ; marks the bundary change between the surface zne and the deep zne m belw sea level. Deep zne: 800m-cean flr. Salinity What s in cean water? f cean water is H 2O The ther is disslved gases and slids such as salts (NaCl) Sdium Chlride is the main salt in the cean Salinity (mainly salts) present in cean water. Average salinity f cean water is (% = parts salt per 1000 parts cean water) 50 millin billin tns f salt in ur seas 1,000 g f seawater cnsists f f disslved salts Large amunts f salinity. Large amunts f salinity. Each year, Earth's rivers carry mre and mre salt int the cean. The water evaprates, but the salt is left behind in the cean The principle surce f disslved salts in the cean is Ocean Resurces Desalinatin - Ocean Acidificatin Excess carbn dixide frm the atmsphere makes its way t the ceans The ceans are a CO 2 acidity f cean water especially (CaCO 3) calcium carbnate rganisms Negative impacts n fisheries Decrease in glbal shellfish prductin and disruptin f livelihds

4 Currents and Climate SWBAT: Categrize cean currents by lcatin, temperatures, surface and density. Ocean Currents Surface Currents Descriptin Currents can be n the surface f the cean r in deep water. The energy that drives surface cean currents cmes frm Gyres Ocean Current Impact n Climate Why d currents mve in a circular pattern? Because f the Earth s rtatin, currents are deflected t the and t the. This is called the Crilis Effect Oceans maintain the balance f heat energy by cean currents cycling between When currents frm lw-latitude regins mve int higher latitudes, they transfer heat frm warmer t cler areas n Earth Ocean currents are especially imprtant t castal regins the air temperatures alng these castal regins An example f this is Deep (density) Currents Factrs that affect the density f seawater: Decreasing temperature and increasing salinity cause water t becme mre dense. Near Antarctica, surface cnditins create the highest density water in the wrld. Evapratin results in increased salinity A simplified mdel f cean circulatin is called cnveyr belt Upwelling Winds blw the warm surface water away and it is replaced by cld waters (with lts f nutrients!) Deep water is very rich in nutrients and is brught t the surface. What s the impact f upwelling? Upwelling revitalizes the cean and keeps the

5 Waves and the Shre SWBAT: Identify features f a wave and f wave ersin and depsitin. Waves Swell Size f a Wave Descriptin Waves are cean energy traveling alng the bundary between the cean and the atmsphere. The pwer f the waves is mst nticeable near the shre. 1. The f the wind. 2. The length f the wind blws. 3. the distance the wind blws Crest: Trugh: Part f a Wave Breakers Wave Height: distance between the Wave Length: Distance between (either crest t crest r trugh t trugh.) The average wave length is 2-3 times the wave s height Waves break in water that is as deep as ne half the wavelength. Energy in a wave- As a wave mves acrss the surface f the cean, nly nt the water! If the cean flr is, the wave breaks If the cean flr is, the wave spills frward with Lngshre Currents Occurs when waves apprach the beach at an angle They ften frm lng sandbars. Refractin Undertw Rip Current Refractin causes Generally a that mves water and sand frm the beach back t the shre. A current that frm the beach carrying sand and water. Hw can a swimmer escape a rip current? Swim

6 Unit 5 Ocean Ntes Name: Wave Ersin and Depsitin Waves alng the shreline are cnstantly Many shreline features can result frm this activity. Descriptin Wave-Cut Cliffs and Platfrms Result frm the cutting actin f the surf Sea Arches and Sea Stacks that extend int the sea, and are n all sides because f, are erded in the center First frming arches and then, when the arch caves in, frming a Barrier Islands Spits Bars Tmbl They are left ver after a rise in sea level ver time Or leftver sandbars after a drp in sea level Shreline Stabilizatin Grins, breakwaters, seawalls, and beach nurishment are designed t Grins, breakwaters, and seawalls require cnstructin while beach nurishment des nt Only ffer t shreline prblems. Beach Nurishment Mst sand cmes frm ffshre. Can be very expensive.

7 Tides SWBAT: Describe the mn s effects n tides, calculate tidal variatins, and identify the mn phases. Tides Tidal Range Descriptin It is caused by the The mn takes 24 hurs and 50 minutes t rbit the earth. Thus, tides shift by Occurrence: Spring Tides Occurrence: Neap Tides Prduce: Prduce: Occurs during the and the phase When the Sun, Earth and Mn line up in a straight line, the cmbined gravity f the Sun and the mn have an effect n the earth s ceans, Happen every Occurs during the and the phase When the Sun, Earth and mn are perpendicular t each ther, their gravitatinal pulls Daily tidal range is at Daily tidal range is at Frictin created between the water and the cean flr slws the rtatin f the earth. (Slwed 10.8 minutes since the dinsaurs died) Diurnal Example: Gulf f Mexic Semidiurnal Example: East Cast Fld Tide Ebb Tide Slack Water Tidal Bre

8