The Waters of the Ocean

 1) A molecule of water is made of two hydrogen atoms and one atom of oxygen  2) Water molecules are held together by hydrogen bonds (weak and easily broken)  3) The states(phases) of water are SOLID(ice) LIQUID(water) GAS(water vapor) 4) Phase is the result of molecular motion (the molecules of water vapor MOVE faster than in ice or liquid water)

Water is a polar molecule (negative at Oxygen and positive at hydrogen) Water molecules bond together with HYDROGEN BONDS

 1) EVAPORATION-if water molecules move fast enough to break free of their hydrogen bonds, the molecules EVAPORATE or change from liquid phase to gas phase  2) MAXIMUM DENSITY OF WATER- As water cools, it gets denser but only to 4 degrees C  Below 4 degrees Celsius, water starts to freeze and gets less dense (Ice floats)  3) Solid ICE-is less dense than liquid water and FLOATS

1)LATENT HEAT OF MELTING-amount of heat required to melt a substance 2) LATENT HEAT OF EVAPORATION-the amount of heat needed to change water into gas. ONLY the FASTEST moving molecules with the most energy EVAPORATE and take energy with them leaving the molecules left behind with a lower temperature. This is called EVAPORATIVE COOLING.

 1) Water is called the Universal Solvent because so many substances dissolve in it  2)Many substances dissolve in water because of its POLARITY (Hydrogen end of water molecule is positive and Oxygen end is negative)  3) Substances like SALTS (IONIC COMPOUND) dissolve in water because of the ATTRACTION of OPPOSITE charges.  4) When salt dissolves, the crystal structure pulls apart and it DISSOCIATES

 Why is the ocean salty?  1) Dissolved solutes come from materials carried to the sea from weathering of land  2) Dissolved solutes come from materials released from the earth’s interior (magma)  3) SOLUTES are the dissolved materials in seawater.  4) CHLORIDE and SODIUM make up most of the solutes dissolved in seawater (85%)

 1)SALINITY is the TOTAL AMOUNT of salts dissolved in seawater  2) For every 1000 grams of seawater there are 35 grams of salts.  3) SALINITY is measured in PARTS PER THOUSAND (ppt)  4) Seawater has an AVERAGE SALINITY of  35 parts per thousand (35ppt)  5) Salinity is measured using a refractometer

Avg. Salinity of Gulf of Mexico- 35 ppt Mobile Bay-Avg. Salinity is 10 ppt INCREASE IN SALINITY (More salt in water) 1) Salinity INCREASES by EVAPORATION 2) SALT does NOT EVAPORATE or FREEZE! DECREASE IN SALINITY (Less salt in water) 1) Rain falls on ocean 2) Precipitation runs off from rain into freshwater rivers into bays and oceans

 1) RULE OF CONSTANT PROPORTIONS- the relative amount if ions in seawater are always the SAME and do NOT change.  2) 85% of SALTS in SEAWATER are always Sodium and Chloride  3) The higher the Salinity, the denser the seawater  4) COLD seawater is denser and saltier  5) Areas of sudden salinity changes are HALOCLINES  6) Areas of sudden temperature changes are THERMOCLINES

 Transparency – how easily light can penetrate through water  TURBIDITY- reduces transparency  TURBIDITY- the amount of material suspended or dissolved in seawater  SECCHI DISK- used to measure turbidity (how far can you see through the water)  Why is Mobile Bay brown?  Why is the water at Destin so clear?

1) Red light penetrates LEAST through water 2) Blue light penetrates MOST (farthest) through water

 1) At surface, air pressure is equal to 1 atmosphere (14.7 lbs. per square inch)  2) For every 33 ft. of depth (10 meters) in the water column, add another atm. of pressure

 THE CORIOLIS EFFECT  Cause- Rotation of the Earth on its axis  EFFECT- Wind and water currents do not move over Earth in a straight line  WIND PATTERNS  1) Winds are caused by uneven heating of the earth’s surface (TEMPERATURE)  2) Warmer air at EQUATOR moves toward POLES but bent by CORIOLIS EFFECT

 TRADE WINDS-winds located from 30 degrees South to 30 degrees North latitude (around EQUATOR) They blow from east towards west  WESTERLIES-winds located in middle latitudes (30-60 deg) and move opposite trade winds (West to East)  EASTERLIES-Winds located in high latitudes  (60-90 deg.) around North/South Poles

 Why does some water flow faster and create currents?  1) Differences in density  2) Differences in temperature  3) Some major wind currents push sea surface and create surface currents (Coriolis effect causes these currents to curve)  WATER SURFACE CURRENTS combine into HUGE circular systems called GYRES  Ocean currents carry vast amounts of heat energy and can change our climate(EL NINO)

 CREST-highest part of the wave  TROUGH-lowest part of the wave  WAVE HEIGHT-vertical  distance between crest  And trough  WAVELENGTH-Distance  from one crest to next  WAVE PERIOD-Time it  takes a wave to pass a  certain point

When wave crests are pushed Up by the wind called SEAS SWELLS are round crests And troughs WAVES BREAK when approaching the shore and Fall forward creating SURF 1)The trough slows down and crest continues at same speed and falls forward

 1) Why are there tides?  Tides are caused by the gravitational PULL  of the MOON and SUN on WATER  2) TIDAL RANGE-the difference in water level between high tide and low tide  3) SPRING TIDES-LARGE difference in high and low tide level  SPRING TIDES caused when the sun and moon are in line with Earth (Full moon and New Moon phases)

 NEAP TIDES- caused when the sun and moon are at RIGHT ANGLES with Earth in center  There is little difference  in high and low tide  levels because the  gravity of sun and  moon cancel each  other out

 Most places in the world have 2 HIGH tides and 2 LOW tides a day = SEMIDIURNAL TIDES  MIXED SEMIDIURNAL TIDES-have 2 low tides and 2 high tides per day but THE ONE HIGH TIDE IS HIGHER THAN THE OTHER  MOBILE has DIURNAL TIDES- only 1 high and 1 low tide per day.  TIDE TABLE- give the predicted time and height of high and low tides for every day of the year (based on phases of the moon)

 Surface layer (Warm layer)- sunlight warms it THERMOCLINE- between warm layer and cold layer (middle) Deep Ocean- DENSEST, COLDEST, SALTIEST Water in Ocean