Waters of the Ocean

Water

It makes up 80% of a Marine Organism’s body.

ex 98% of a jelly fish

Other properties of water

Adhesive – ability to attract to objectsCohesive – ability to attract to other water molecules.

Hydrogen bonding occurs between water molecules. When Hydrogen is attracted to highly electronegative atom.Electronegativity- ability of an atom to attract electrons towards itself.

Nature of WaterAll matter is made up of atoms.Matter-Anything that has mass and takes up

space.Atoms – smallest unit of matterElements – Substance composed of

individual atoms of the same kind. 104 known elementsMolecule is two or more atoms that are

forced together. H20 is made up of 2 H atoms and 1 O atom.

Hydrogen bonding between water molecules

Water is a Polar molecule

Uneven distribution of charged due to electrons not shared equally. This causes a partial negative on the Oxygen.

The electrons are pulled toward the Oxygen that creates this uneven distribution of charge.

Creates an Universal solvent.“Like dissolves Like” Polar substances

dissolve other polar substances

Water molecules

Physical States of Water

Exist in three states liquid, solid and gaseous

Triple Point of water- When conditions are right. Conditions meaning temperature, pressure and volume, water can exist in all three states at once.

Changes of State

Requires energy.Temperature reflects the average speed of

the moleculesMelting- solid to liquid Energy required – Latent heat of melting. Molecules begin to vibrate and break bonds to move away as temperature increases. Energy is absorbed by the bonds not into the speed of the molecular motion.

As the atoms breaks free, molecules speed increases with temperature.

Water has a High Heat Capacity- Specific heat.

1.0 g/degree C

Latent heat of evaporation ( heat of Vaporization)

Heat of fusion – Liquid to a solid

All Changes of state requires a steady temperature except the specific heat of a substance that is depend on a change in temperature.

Water as a Universal Solvent

Dissolves Salts – Combinations of particles with opposite charges.

Ions- Particles that have given electrons away ( +) or receive electrons (- )

Crystals break apart from the water molecule pulling on the ions. Then once the ion is off, other water molecules congregate around it and carry it into solution.

 

Sea Water

Salts come from two main sources.Chemical weathering of RocksFrom the earth interior through the

hydrothermal vents.Six ions compose 98% of the solutes in

sea water Na and Cl ions makeup 85% of the solids. 

Salinity

Total amounts of salt dissolved in sea water. It is expressed over 1000 g of seawater that has been evaporated If you have 35 g of salt left, then the salinity is 35 o/oo parts per 1000.

 Organisms are affected by the kind of ions not

the amount in the water. DITTMAR – A scientist that tested salt water

for the consistency of ions in the water. Found the the amount did not vary.

Salinity

Changes in salinity is controlled by : Precipitation Evaporation Freezing - ice is pure

water/salt separates from it.All processes occur at the surface.

Salinity continued.

Average Salinity – 35 0/ooOpen Ocean varies from 33 – 37 0/ooRed Sea 40 o/00. Due to being partially

enclosed.Baltic Sea 7 0/oo. Due to river runoff. 

Salinity- Temperature - Density

Saltier the water, the denser.Density depends on temperature and salinity of water.Open Ocean temperature 28 F to 86 F Salt water freezes below 0 C.Temperature varies considerable in the ocean. It is

measured with a reversible thermometer. The mercury column breaks when inverted at the temperature reading from the water column.

A series of these thermometers are use to develop a ocean profile.

 

Dissolved gases

Oxygen, Carbon Dioxide, NitrogenGas Exchange between ocean and

atmosphere occurs through a variety of processes.

Transparency

Sunlight needed for plants to produce oxygen.

Depends on materials on the water.Ocean water is most transparent to blue

light from the visible spectrum of white light.

Consist of: R O Y G B I V 

Pressure

Land organisms are less than 1 atmosphere of pressure.

Pressure increases with depth with every 10 m another atmosphere is added.

Gases are compressed, Gas filled structures tend to collapse.

Ocean Circulation

Surface Circulation - surface currents are driven by wind.

Coriolis effect influences surface current and wind - Earth rotates and is round which causes anything moving to be not in a straight line. In the Northern Hemisphere we tend to deflect to the right. In the Southern Hemisphere we tend to deflect to the left.

Wind patterns

Wind patterns winds driven by heat energy of the sun. Sun is directly over the equator. This causes direct heating. Warm air rises. Cooler air is sucked in this area and this creates wind. Winds are bent due to Corioles Effect.

 Trade Winds - blow at 45° angles towards the

equator. They are the steadiest winds on Earth/ Why? No land around.

 

Westerlies - middle latitudes - moves opposite of trade winds - variable.   Polar Easterlies - high latitudes - most variable winds - these are

the most variable. Variable winds move opposite of Trade Winds.   Surface currents - all major surface current are driven by winds. . Winds push the upper layer of the surface layer and moves at 45˚

angle. 2nd layer moves slightly to the right and slower. Upper part of surface current is called the Ekman Layer and they tend to move at 90˚ from the wind direction. Layers of water move in different directions and rates called the Eckman Transport

 

Gyres - huge circular movements of currents that carries warm water in one direction - regulate climate.

 

Cold water is carried in another direction. Currents regulate the climate on the Earth.

Carrying heat from the tropics to polar regions.

Continental shelf - currents tend to shape the bottom, shape coastline and affects tides.

 

Stability and Overturn

Ocean is layered or stratifiedDense water is on the bottom to the least at

the top.Surface water stay always on top of the

column of water is stableOnly the winds and waves mix the deep water

with the surface.Greater the difference in density the more

stable the water column.

Overturn

Surface Water sinks displacing less dense water below

Profile (temperature ) is straight down,Occurs in the temperate and Polar regions in

the winter when the surface water cools. It bring oxygen rich surface water to the

deep sea.

3 Layered ocean

Processes Changing: Temperature Evaporating- cooling Solar heating Heat exchange with the atmosphere.Water masses finger printed by temperature and salinity. This aids in the following circulation

3 layered ocean continued

 1. Surface Layer--330 ft- 660 ft deep--Mixed by wind, waves and currents.Called the mix layer--- Thermo cline occurs with a sudden

temperature changes due to surface heating.

Intermediate Layer 1500 m (5,000) deep Main Thermocline Zone of Transition between warm

surface water and cold water below and rarely breaks down,

Deep Bottom Layers 1,500 m (5,000 feet) uniformly cold less than 4 C

Waves

Wind causes waves/Wind is caused by the uneven heating of the

earth.Waves carry energy over the surface.Water molecules do not move – only circular.The faster, longer the wind blows . The longer

the wave.

Period – time it take a wave to go by any given point

Fetch- determines the size of wave span of open water over which the wind blows.

Seas

Wave Diagram

Fetch determines the wave span over the open water that the wave travels

Waves approaching shore- waves reaching a shallow area, wave will touch bottom.

Bottom forces water molecules to travel in an elongated ellipses.

Water molecules approaching shore.

Swells

Waves cont……….

This tends to slow the wave down .The wave catches up and pile up.Creating a shorter wave length.Wave becomes steeper and falls over as surf.White water effect is the water mixing with

oxygen.

Breaking Waves

Breaker waves

Tsunami

Originated from a Japanese word meaning “Harbor wave”, also called a Tsunami wave train. ‘Also called tidal wave.They are a series of water waves caused by the displacement of a large volume of a body of water?It can occur in a lake besides in a ocean.

Tsunami Wave Train

Tsunami in Japan

Causes

EarthquakeVolcanic eruptionsUnderwater explosionLandslidesGlacier calving and other mass movements

Oceanographer – seismic sea waves First recognized in 425 B.C. Japan has the largest history.Tsunami are difficult to detect over deep

water as the Tsunami approaches shore, water becomes shallow.

Wave Shoaling compresses the wave.Velocity slows below 50 mphWavelengths diminishes to 12 mph, amplitude

grow.The wave does not break. It flows in, then

out.

Wave Shoaling

Tides

Rising and falling of water in rhythmic patterns.

Dominant influence on the seashore.It is caused by the gravitational pull of the

moon and sun and by the rotation of the earth around the sun.

Moon and earth are held together by gravitational attraction

Spring Tides

Occur throughout the year.Tidal range is large.Occurs when the sun and moon are in line

with the earth

Neap Tides

Tidal Range is smallSun and moon are at right angles.Occurs at the 1st quarter and 3rd quarter of

the month.

Tides –Real World

Semi diurnal tides- 2 high tides and 2 low tides a day.

Where? East coast of N. America and most of Europe and all of Africa

Mix Diurnal Tides

Successive high tides of different heights.Where? West Coast of N. America and

Canada

Diurnal Tides

One High tide and one low tide everyday.Where? Coast of Antarctic , part of the Gulf of

Mexico, Caribbean and Pacific.

Where does diurnal tides occur?

What affect Tides?

Tide tables predict the time of the tides.What is used to create Tide Tables: 1. Islands, continents, ridges, basins,

canyons, reefs- all affect tides. 2. Variations of orbits of sun and moon. Relative to the equator 3. Weather

Tidal Range

Difference in water level between successive high and low tides