2.2 The global energy budget Flashcards

1
Q

What are winds?

A

Moving air masses - large bodies of air which are almost uniform horizontally in temperature and moisture characteristics. They are separated from adjacent different air masses by frontal zones.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are air masses classified as?

A

1) Continental or maritime

2) Arctic, Antarctic, equatorial, tropical, or polar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the temperature and humidity at equatorial maritime?

A

Warm and very moist e.g. Indian ocean

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the temperature and humidity at tropical maritime?

A

Mild in winter, warm in summer; moist, e.g. N/S Atlantic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the temperature and humidity at tropical continental?

A

Very warm and dry. e.g. Australia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the temperature and humidity at polar maritime?

A

Cool and moist e.g. Arctic ocean

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the temperature and humidity at polar continental?

A

Cold and dry e.g. Canada

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the temperature and humidity at continental arctic and Antarctic?

A

Very cold and very dry e.g. Antarctic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the Coriolis effect?

A

Due to the Earth’s rotation, winds can’t travel is straight lights; they are deflected.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the speed of air movement determined by?

A

The pressure gradient. Steep gradient = strong winds - close isobars

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is Ferrel’s Law?

A

Any moving body in the northern hemisphere will be deflected to its right and any moving body in the southern hemisphere will be deflected to its left.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the trade winds?

A

Surface winds blowing in the Hadley cell are deflected to the west

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the polar easterlies?

A

Surface winds in the polar cell moving towards the equator are deflected to the right in NH or left in SH.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the prevailing westerlies?

A

Surface winds in the Ferrel cell are blowing in a different direction to the two cells either side of them. Northwards in NH, southwards in SH. Winds in NH are deflected to the right, winds in SH are deflected to the left.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the Doldrums?

A

Nickname given to the area (0-5ºN/S) around the equator, that serves as the meeting place for the two trade winds in each hemisphere. Leads to very calm waters.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the horse latitudes?

A

30º N/S where cool descending air creates period of calm weather

17
Q

Why do winds near the surface lose energy and speed?

A

Due to friction, reducing geostrophic force. As a result, pressure gradient force is no longer balanced by the Coriolis force.

18
Q

What are the upper westerlies?

A

Fast moving westerly winds between 30 and 50 degrees. Occur at the top of the troposphere.

19
Q

What are the causes of the upper westerlies?

A

1) Temperature/pressure gradient = they blow in response to the strong difference in temperature gradient between polar and tropical air meeting. This generates a high-pressure gradient.
2) Coriolis force - causes air to deflect east as it travels towards the poles and become geostrophic.

20
Q

What is a jet stream?

A

A narrow ribbon if very fast-moving air that runs through the centre of Rossby waves. There are 2 jet streams in each hemisphere: Polar jet stream and sub-tropical jet stream.

21
Q

What are Rossby waves?

A

When temperature and pressure gradients weaken, the jet stream can meander in large curving paths known as Rossby waves.
They are belts of upper-air westerlies, which follow a meandering path around the earth.
When they meander in large curving paths it can lead to the separation of ‘pools’ of warmer air surrounded by colder air, or vice versa. They help transfer heat north and cold south. They are much slower moving than the jet streams.
They may be caused by a disturbance in the airflow.

22
Q

Where is the polar front jet stream found?

A

Between 40-60ºN/S - forms the division between Ferrel and polar cells.

23
Q

Where is the sub-tropical jet stream found?

A

25-30ºN/S, marking the boundary between the Hadley cell and Ferrel cell.