Hazardous Earth - Global Circulation and the ITCZ Flashcards
1
Q
How and why does latitude impact temperature?
A
- Higher latitudes have colder temperatures - further from the equator
- Lower latitudes have warmer temperatures - closer to the equator
2
Q
How is heat distributed?
A
- Air movement by pressure difference
- Ocean Currents
3
Q
Pressure Differences
A
- Warm air rises (low air pressure) less air pressing on the ground
- Cols air sinks (high air pressure) more air pressing on the ground
- Air always travels from high to low pressure
4
Q
Global Circulation Model
A
A theory that explains how the atmosphere operates in 3 cells either side of the equator
5
Q
Hadley Cell
A
Warm, moist air rises and travels west
- This forms cumulonimbus clouds (water vapour in the air condenses)
- Heavy rainfall near the Equator
6
Q
Ferrel Cell
A
- Warm air cools down
- Cold, dry air sinks and travels East
-Dry weather in North Africa and South-East Asia
7
Q
Polar Cell
A
- Cool air sinks
- Causes cool, dry weather at the poles
- Some air transfers to the Ferrel Cell
8
Q
ITCZ (Intertropical Converge Zone)
A
- Belt of low pressure air that circles the earth near the equator where trade winds of the North and South Hemispheres join
- Occurs between 2 Hadley cells
9
Q
Direction of trade winds
A
Northern Hemisphere:
- Move to the right (called North East trade winds)
Southern Hemisphere:
- Move to the left (called South East trade winds)
10
Q
ITCZ in July
A
- Sun is over Tropic of Capricorn
- ITCZ moves north
- Brings rain to North Hemisphere (e.g. West Africa)
11
Q
ITCZ in January
A
- Sun is over Tropic of Cancer
- ITCZ moves south
- Brings rain to South Hemisphere (e.g. South Africa)
12
Q
Ocean Currents
A
Redistribute warmer water form the Equator and colder water from the Arctic and the Antarctic
13
Q
What drives an ocean current?
A
- Wind
- Tides
- Changes in water density
- Rotation of the earth
