Unit 3 Oceanography

Water Molecule

2 hydrogens & an oxygen

Bonding

the action of joining things securely by means of heat, pressure or chemical bonds

Dihydrogen Oxide

water molecule

Dipole Molecule

one side of the molecule is more positive or negative than the other side

Dipole Moment

numerical value of how polar a molecule is

Salt

Sodium & Chloride

Hydrogen Bond

a bond between a hydrogen & another atom, typically oxygen, nitrogen and fluorine

Acid

releases hydrogen ions in water/aqueous solutions; sour taste (e.g. vinegar, citrus & fruits)

Hydrogen Ion

positively charged particle formed when a hydrogen atom loses its only electron

Base

produces hydroxide ions (OH-) in aqueous solutions; slimy (e.g. soap)

Hydroxyl Ion

when a bonded oxygen & hydrogen gain an extra electron, providing a negative charge

Unstructured Water

all water molecules at 100 degrees C and are condensed; independent water molecules

Structured Water

hydrogen bonds force water molecules to link with hydrogens to form a hexagon ring; by 0 degrees C all molecules are in hexagons

Heat

energy that causes electrons to vibrate or move

Sensible Heat

causes something to get warmer or cooler without causing a phase change

Latent Heat

supplying energy to a material results in a change in physical state but NOT a change in temperature

Temperature

measured via thermometer; physical measure of kinetic energy of molecules to define hotness or coolness

Thermometer

measures thermal contraction/expansion; mercury has a large coefficnet of expansion

Calorie

amount of heat needed to raise the temperature of 1 gram of water by 1 degree C

Density

weight (g) / volume (cm3)

Density Stratified System

vertical layers of fluids (air or water) where denser, heavier layers sink below lighter, less dense layers

Photosynthesis

CO2 + H2O + light —> Glucose + O2; 200m deep

Oxygen Minimum Zone

no specific depth; contains the lowest oxygen levels in the ocean

Oxygenated

water contains dissolved oxygen

Dysoxic

marine area/zone with very low dissolved oxygen

Anoxic

marine area/zone with no dissolved oxygen; there are no naturally occurring in the ocean (e.g. human created); dead zones

Carbon Dioxide

2 carbons and an oxygen

Carbonate Ion

CO_3^2-

Bicarbonate Ion

HCO_3^-

Carbonic Acid

H₂CO₃

Reflection

sound waves go from the source —> surface —> receiver; sound waves are straight lines

Refraction

bending of sound wave; refracts towards where the sound is travelling slower; sound in colder water lags behind and curves

Shadow Zone

when sonar cannot detect a submarine

Sound Channel / SOFAR Channel

natural, deep-ocean layer around 1000 meters deep that acts as a waveguide for sound; allows for low-frequency sounds to travel thousands of miles

Scattering

random reflection of sound waves

Sonar

underwater detection technology using acoustic pulses to map the seafloor & locate objects

Spicules

ice crystals that are 1-2 cm in length

Cells

ice that traps water on all sides

Low Pressure Systems

rising warmer air

High Pressure Systems

descending, colder air

Advection

movement of air parallel to the surface of the Earth from areas of high to low pressure

Convection

winds do not occur in these regions where ascending or descending air because air is not moving parallel to Earth’s surface

High Altitude Wind

at some altitude, air above is less dense, and the rising & warmed air stops rising and begins to flow poleward

Surface Wind

air at surface flows equatorward; is warmed & ascends at the equator

Convection Cells

three in each hemisphere; cells form bands around Earth; cells are not closed & there is considerable mixing of air among them

Hadley Cells

equatorial cell, 0-30 degrees N,S; well defined; warm air rises at the equator —> moves poleward —> sinks near 30 degrees N,S —> flows back to equator as a surface wind

Temperate/Ferrell Cells

poorly defined; between Hadley & Polar cells; between 30-60 degrees N,S; some air flows poleward as surface wind & becomes warmer; some air flows upward until 60 degrees N,S & collides with cold air coming from the pole —> ascends & cools

Polar Cell

poorly defined; at 60 degrees N,S; driven by uneven heating, cold air that sinks at the poles and moves toward 60 degrees N,S, then warms & rises

Coriolis Deflection

deflection of objects relative to Earth’s surface because of the differences in linear rotational speed from equator to pole

Trade Winds

from 30-0 degrees N,S; blows at 16-25 km/hr; blows almost continuously; equatorial easterlies

Westerlies

winds from 30-60 degrees N,S

Polar Easterlies

winds from 90-60 degrees N,S

Windless Belts

areas of high or low pressure

Doldrums/Intertropical Convergence Zone

0 degrees (equator) where air is ascending & not moving parallel along Earth’s surface; low pressure (ascendance)

Horse Latitudes/Subtropical High Pressure

30 degrees N,S where air is subsiding & not moving parallel along Earth’s surface; high pressure (subsidence)

Subpolar Lows

60 degrees N,S where air is ascending & not moving parallel along Earth’s surface; low pressure (ascendance)

Polar Highs

90 degrees N,S where air is subsiding & not moving parallel along Earth’s surface; high pressure (subsidence)

Eckman Spiral

consequence of the Coriolis Effect, when surface water molecules move by the force of the wind they drag deeper layers of water molecules below them

Boundary Current

oceanic flows found along the edges of ocean basins; two types: western & eastern

Gyre

a large system of circulating ocean currents formed by global wind patterns, Earth’s rotation (Coriolis effect) and landmasses

Antarctic Circumpolar Current

an ocean current that flows clockwise from west to east around Antarctica

Equatorial Countercurrents

surface currents that flow in the opposite direction of gyres (flows eastward); produced by gravity & wind-driven

Equatorial Undercurrents

flows from South America to Africa; water flows uphill; pressure current; flows directly along the equator; fast-flowing