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Question 1

What do we mean by shortwave radiation?

Answer 1

Radiation from the sun, also called solar radiation

Question 2

What is attenuation of light?

Answer 2

Reduced intensity of solar radiation due to light scattering and absorption

Question 3

What is the connection between attenuation of light and heating of surface water?

Answer 3

Absorption transfers radiation into heat

Question 4

How does a large attenuation coefficient affect heating of the ocean?

Answer 4

A large attenuation coefficient means rapid attenuation with depth, and thus much absorption that transfers radiation into heat.

Question 5

Why is the ocean blue?

Answer 5

Blue light penetrates the deepest in a clear ocean. Blue light is scattered most and absorbed the least. Therefore both the sky and the ocean are blue.

Question 6

What makes sound propagate?

Answer 6

Sound propagates as pressure waves utilizing compressibility of the medium it propagates in. Larger compressibility means slower sound propagation speed.

Question 7

How does the sound speed depend on temperature and pressure?

Answer 7

Sound speed decreases with decreasing temperature, but increases with increasing pressure.

Question 8

What do we mean by net surface heat flux?

Answer 8

The sum of the four different types of heat fluxes exchanging heat across the ocean surface; the difference between fluxes that heats the ocean and fluxes that cools the ocean.

Question 9

What are the four different types of surface heat flux?

Answer 9

1. Solar radiation (shortwave radiation) 2. Longwave radiation (infrared) 3. Latent heat flux (evaporation/ice melting) 4. Sensible heat flux (heat conduction)

Question 10

Which factors influence solar radiation?

Answer 10

Solar noon altitude, surface albedo, clouds and water vapor in the atmosphere.

Question 11

Which factors influence longwave radiation?

Answer 11

Ocean surface temperature, clouds and water vapor in the atmosphere.

Question 12

Which factors influence latent heat flux?

Answer 12

Degree of saturation of water vapor in the air near the ocean surface, and wind speed near the ocean surface.

Question 13

Which factors influence sensible heat flux?

Answer 13

Temperature difference between the ocean surface and in the air near the surface, and wind speed near the ocean surface.

Question 14

What is Molecular diffusion?

Answer 14

Spreading of a compound from high concentration towards low concentration (down-gradient diffusion)

Question 15

Explain molecular viscosity and diffusion

Answer 15

Random movement of water molecules act as friction on currents (viscosity) and
spread properties of the water (diffusion).

Question 16

What is the difference between turbulent and molecular viscosity and diffusion?

Answer 16

Internal friction and spreading due to molecular movement or turbulent movement.
Turbulent diffusion/viscosity is much faster than molecular diffusion/viscosity.

Question 17

What in principle is the Kolmogorov length scale?

Answer 17

The smallest size of whirls in turbulence. Below this length scale turbulence is dissipated into heat.

Question 18

Why is vertical (diapycnal) eddy diffusion generally smaller than horizontal (isopycnal) eddy diffusion?

Answer 18

Stability inhibit vertical movement, reducing the vertical size of whirls in turbulence.

Question 19

What generates eddies and turbulence?

Answer 19

Generally a vertical or horizontal current shear, often between density layers.

Question 20

What does the Richardsons number tell us?

Answer 20

The relative strength between the stability restoring force and the turbulence generation force (current shear). If the number is small, the flow is turbulent.

Question 21

What do we mean by steady state?

Answer 21

A property of the fluid inside a specific volume is in steady state of its value does not change with time

Question 22

What is the principle behind Knudsen’s relations?

Answer 22

Knudsen’s relations combines conservation of salt and conservation of volume in a basin with freshwater supply and water exchange with an adjacent ocean.