Lec 6. Global Energy Movement

Question 1

how is solar radiation distributed across the globe

Answer 1

It is concentrated at the equator, but it stretches near the “top” North and “bottom” South, the area absorbing the energy is greater at the poles

Question 2

how does solar radiation distribution impact the global energy?

Answer 2

• it creates energy surpluses and deficits.

At the poles; Energy emitted as IR radiation is greater than solar radiation being absorbed.

Question 3

At what latitude is there an energy deficit (negative net radiation) ?

Answer 3

above 35° lattitude !

Question 4

why are areas above the 35° latitude not cooling down if they have an energy deficit?

Answer 4

It has to do with the global systems that are in place; that transfer surplus heat from the equator to the colder regions at the higher lattitudes

Question 5

What are the 2 main systems that move the energy surplus ?

Answer 5

Atmospheric circulation
Oceanic circulation

Question 6

What are the 4 types of movement that are part of the atmospheric circulation?

Answer 6

1. pressure-driven air movement
2. landform-driven air movement
3. rotation driven air-movement
4. water vapor transport

Question 7

What are the 2 currents found in the oceanic circulation?

Answer 7

1. Surface ocean currents
2. Deep ocean currents

Question 8

what is air pressure?

Answer 8

the weight of molecules pressing down on each other in the atmosphere

Question 9

How does air move when it is under high pressure?

Answer 9

it gets pulled towards the areas with lower pressure

Question 10

what is the relation between temperature, air, density and pressure

Answer 10

Pressure = Density x (constant) x Temperature

Question 11

what is an air parcel?

Answer 11

an area of air that is of a different temperature or pressure than the surrounding air

Question 12

What is the initial cause of pressure-driven air movement?

Answer 12

the uneven distribution of solar radiations on the planet

Question 13

why is there snow on top of mountains even in the equator?

Answer 13

Because of landform-driven air movement, Higher reliefs of landforms force parcels of air higher into the atmosphere,
As air is forced upwards:
- Decrease in pressure, molecules in. the air expand, they lose energy, air becomes colder

Question 14

How does the rotation of the planet affect air movement?

Answer 14

Mouvement which would normally be straight actually curves with the rotation of the planet (the Coriolis effect)

Question 15

Do they release or take in energy?
1. Evaporation
2. Condensation

Answer 15

1. takes in
2. releases

Question 16

when is condensation common in the atmosphere?

Answer 16

1. air temperatures decrease
2. where air rises and expands

Question 17

what are common scenarios where condensation happens?

Answer 17

• circulation cells where warm and humid air rises, and as a result expands and cools
• on the side of a high landform as an air parcel is pushed vertically upwards and cools
• at night, as air temperatures decrease in response to the loss of incoming solar radiation

Question 18

what are the 3 main circulation cells

Answer 18

1. Hadley Cell
2. Ferrel Cell
3. Polar Cell

Question 19

What is the Polar cell?

Answer 19

It starts at 60° north and south and ends up falling at the polar regions
much colder but enough of an energy different to drive a circulation cell

Question 20

What is the Hadley Cell?

Answer 20

It is the big circulation cell
starts at the equator
goes 30° north and south
relatively free of water vapor

Question 21

What is the Ferrel Cell?

Answer 21

• rises at 60° and falls at 30°
• moves in the opposite direction of the Hadley and Polar
• driven by the movement of the Hadley and the Polar
• weaker and more variable

Question 22

what are surface winds?

Answer 22

• global pattern of movement of air in the atmosphere
• driven by circulation cells and the rotation of the planet (Coriolis effect)

Question 23

what are surface currents driven by?

Answer 23

surface winds

Question 24

what do landforms do to currents?

Answer 24

they can trap or deflect currents

Question 25

what are the differences that drive deep ocean circulation?

Answer 25

it is driven by differences in water density (impacted by temperature and salinity)

Question 26

what is the cause of ocean salinity?

Answer 26

minerals weathered from land and both evaporation and ice formation in the ocean

Question 27

what is the major driver behind deep ocean circulation?

Answer 27

cold polar regions
- colder water (dense)
- greater salinity (driven by ice formation)

Question 28

why does adding salt to roads delay ice formation?

Answer 28

because as ice forms, salts and minerals need to be left behind

Question 29

how does ice formation lead to greater salinity levels?

Answer 29

The water left behind by ice formation has a higher salinity because when ice forms, salts and minerals are left behind

Question 30

what is the thermohaline circulation?

Answer 30

it is the coming together of the surface currents and the deep ocean currents, forming a global circulation of oceanic currents

salt temperature driven circulation