Lecture 1 & 2

Question 1

Purpose of Oceanography

Answer 1

ocean circulation and climate linked

Question 2

Fundamental Properties of Water

Answer 2

1) Temperature
2) Salinity
3) Desnity
4) Transmission of light and sound

Question 3

Structure of pure water

Answer 3

H2O covalently bonded @105 degrees -> charge bias
High surface tension due to ‘stick’ of molecules
High heat capacity
High latent heat capacity
Density = max @3.98 degrees

Question 4

Latent heat capacity

Answer 4

heat/energy needed to phase change

Question 5

Effect of adding salt

Answer 5

Increased
o Boiling point
o Density
o Surface tension
o Electrical conductivity (due to charges)
o Osmotic pressure
Decreased
o Heat capacity  Less heat required to raise the temperature
o Freezing point  Extra ions disrupt ice crystal formation
o Maximum density temperature  Extra ions change packing arrangements
o Vapour pressure

Question 6

Osmotic Pressure

Answer 6

molecules from high concentration to low concentration

Question 7

Factors influencing ocean temperature

Answer 7

Solar radiation = more at equator and less at poles

Question 8

How does the ocean moderates Earth’s temperature

Answer 8

Thermal inertia of ocean surface water
o Annual freezing and thawing of ice
o Movement of water vapour from tropics to poles

Question 9

Temperature profile

Answer 9

Epipelagic zone heated most
Epilimnion = mixed layer (50-500m)
Thermocline = Rapid temp decrease (500m - 1000m) seasonal @ mid-lat, max @ summer + absent winter
high-lat -> thin/absent (maintained by upwelling)
Hypolimnion = deep ocean (>2500m)

Question 10

Salinity of ocean

Answer 10

Surface = similar to temperature (not equator)
controlled by evaporation/precipitation
Variation = freshwater discharge/storms

Question 11

Salinity profile

Answer 11

Well-mixed, halocline, deep ocean

Question 12

Density increases with

Answer 12

increasing salinity and pressure

decreasing temperature

Question 13

How do we measure density?

Answer 13

salinity, pressure + temp

Question 14

Potential Density

Answer 14

corrected density for compression

Question 15

Density profile

Answer 15

well-mixed, pycnocline - barrier to mixing + freezing, deep ocean

Question 16

Light Absorption

Answer 16

Purple/red absorbed rapidly (ultrared/infrared)

blue/green reflected

Question 17

Sound travelling in water

Answer 17

3x faster in water

Highly NON-LINEAR

Question 18

Instruments to Measure Water Properties

Answer 18

CTD Measurement (Conductivity - Salinity, Temperature, Depth - pressure)
Bathythermographs
-	Provide vertical profile of temperature & pressure
-	Sensor head freefalls while transmitting data back through uncoiling wire
Drifters
-	SOFAR Float
-	RAFOS
-	ARGO
-	ALACE
-	PALACE
-	APEX
-	Slocum Glider

Question 19

Shadow zones

Answer 19

A zone where the divergence of sound waves creates a region that has little sound energy penetration.