CHEMICAL and CHEMICAL and PHYSICAL PHYSICAL FEATURESFEATURES

CHAPTER 1CHAPTER 1

MARINE BIOLOGYMARINE BIOLOGY

The Nature of WaterThe Nature of Water

A water molecule A water molecule is made up of one is made up of one oxygen and two oxygen and two smaller hydrogen smaller hydrogen atoms.atoms.

Water molecules Water molecules are held together are held together by hydrogen by hydrogen bonds.bonds.

Water striderWater strider

Water can exist in Water can exist in three different three different states: Solid, states: Solid, Liquid or GasLiquid or Gas

The temp. will The temp. will determine the determine the state.state.

When the temp. goes up, the liquid When the temp. goes up, the liquid water turns into a vapor phase – water turns into a vapor phase – EvaporationEvaporation

As liquid water cools, it becomes As liquid water cools, it becomes denser and sinks in the water denser and sinks in the water column.column.

Density =mass/volumeDensity =mass/volume

Heat and WaterHeat and Water

It takes a large amount of energy It takes a large amount of energy (heat) to change the state of water.(heat) to change the state of water.

Latent heat of melting = the amount Latent heat of melting = the amount of heat needed to melt a substance.of heat needed to melt a substance.

Water has a very high latent heat.Water has a very high latent heat. Heat capacity = how much heat a Heat capacity = how much heat a

substance can store.substance can store. Water has one of the highest heat cap.Water has one of the highest heat cap.

Water can also absorb a lot heat Water can also absorb a lot heat when it evaporates.when it evaporates.

Latent heat of evaporation.Latent heat of evaporation. These unique properties are a result These unique properties are a result

of the hydrogen bonds.of the hydrogen bonds. (demo)(demo)

Water as a SolventWater as a Solvent

Water is known as the universal solventWater is known as the universal solvent It does a very good job of dissolving It does a very good job of dissolving

SaltsSalts The ionic bond between Na and Cl The ionic bond between Na and Cl

becomes weak in water because the ion becomes weak in water because the ion is surrounded by a water molecule is surrounded by a water molecule which insulates the charges ( think which insulates the charges ( think about a wire in your house)about a wire in your house)

SeawaterSeawater

The salts came The salts came from weathering from weathering and hydrothermal and hydrothermal vents.vents.

The amount of salts in the seawater is The amount of salts in the seawater is called Salinitycalled Salinity

We measure this in parts per thousand We measure this in parts per thousand or PPT.or PPT.

The avr. Ocean salinty is 35 ppt.The avr. Ocean salinty is 35 ppt. Salinity in L.I.S. =10-20 ppt.Salinity in L.I.S. =10-20 ppt. We may only see 1-5 pp. Why?We may only see 1-5 pp. Why? The instrument we use is called a The instrument we use is called a

salinometersalinometer

We can also collect We can also collect this data at various this data at various depths with the depths with the use of sampling use of sampling bottles (Niskin bottles (Niskin Bottles)Bottles)

Dissolved gassesDissolved gasses

Oxygen, carbon dioxide and nitrogen Oxygen, carbon dioxide and nitrogen are found in the oceans are found in the oceans

The one we are most concern with The one we are most concern with oxygenoxygen

A good level would be 5 ppm.A good level would be 5 ppm.

HypoxiaHypoxia

When D.O. is consumed faster than When D.O. is consumed faster than it is supplied.it is supplied.

In the summer we are prone to low In the summer we are prone to low levels do to calm water and the levels do to calm water and the solubility of oxygen is lower at solubility of oxygen is lower at higher temps.higher temps.

http://www.mysound.uconn.edu/nwin_wq.html

TransparencyTransparency

Sunlight needs to Sunlight needs to penetrate the penetrate the water for water for photosynthesis to photosynthesis to occuroccur

To measure this To measure this we use a Secchi we use a Secchi diskdisk

Water DensityWater Density At sea level the pressure is 1 At sea level the pressure is 1

atmosphere =14.7 pounds per square atmosphere =14.7 pounds per square inch (psi)inch (psi)

Every 10 meters you increase by one Every 10 meters you increase by one atmosphereatmosphere

To adjust to the depth organisms use To adjust to the depth organisms use swim bladders and the production of oilsswim bladders and the production of oils

If organisms with gas filled structures If organisms with gas filled structures may be injured when brought up to fast may be injured when brought up to fast or from great depths.or from great depths.

Put It All TogetherPut It All Together

Wind and CurrentsWind and Currents

Winds are caused Winds are caused by heat energy of by heat energy of the sunthe sun

The Coriolis Effect- The Coriolis Effect- since the earth is since the earth is rotating air moving rotating air moving over the surface over the surface tends to turn.tends to turn.

CurrentsCurrents

Wind drives Wind drives surface currentssurface currents

WavesWaves

Wind causes wavesWind causes waves

Fetch- The Fetch- The distance over open distance over open water which the water which the wind blows to form wind blows to form waves waves

What is our fetch ?What is our fetch ?

SwellsSwells Surf zoneSurf zone BreakersBreakers

TidesTides

The periodic rise and fall of the level The periodic rise and fall of the level of the oceanof the ocean

Caused by the gravitational pull of Caused by the gravitational pull of the sun and moon as well as the the sun and moon as well as the centrifugal forcecentrifugal force

It takes the moon 24 hours and 50 It takes the moon 24 hours and 50 min. to circle the earth = full tidal min. to circle the earth = full tidal cyclecycle

We have two high We have two high tides and two low tides and two low tides every 24hrs. tides every 24hrs. And 50 mins.And 50 mins.

This is called This is called semidiurnal tidessemidiurnal tides

http://www.tidelinesonline.com/displayPredictions.do?locationInfo=2115-1265-South+Norwalk-6&month=2&day=8&year=2008

When you only When you only have one per day it have one per day it is diurnalis diurnal

Usually very large Usually very large tidal range tidal range (distance between (distance between high and low)high and low)

Bay of fundy = 50 Bay of fundy = 50 ft +ft +

Norwalk 6-7 ft.Norwalk 6-7 ft.

Some places have Some places have tides that don’t tides that don’t follow a pattern follow a pattern

When the moon and sun line up we When the moon and sun line up we get the largest tidal rangeget the largest tidal range

Full moon Full moon New moon New moon QuartersQuarters Spring tide Spring tide Neap tideNeap tide

Can We Predict Tides?Can We Predict Tides?

We use tide tablesWe use tide tables Since we have semidiurnal tides we Since we have semidiurnal tides we

can Divide the 24hrs.+50 min. into can Divide the 24hrs.+50 min. into four time blocks each 6 hrs.+12 min.four time blocks each 6 hrs.+12 min.

If high tide was at 12 noon low If high tide was at 12 noon low would be at 6:12 amwould be at 6:12 am

When would the next high tide be?When would the next high tide be?

How Animals Use TidesHow Animals Use Tides

Horseshoe crabHorseshoe crab Coffeebean snailCoffeebean snail Sea turtlesSea turtles

Coffee Bean SnailCoffee Bean Snail

End of Chapter 3End of Chapter 3