2.2. The Global Energy Budget

Question 1

Troposphere

Answer 1

The first major layer of Earth’s atmosphere. It is warmer when nearer to Earth but then gets colder towards the Stratosphere. It is 8-20km high.

Question 2

Stratosphere

Answer 2

The second major layer of Earth’s atmosphere. It is colder at the lower stratosphere, where it is near the Troposphere, but is warmer at high stratosphere.

Question 3

Solstice

Answer 3

Two times of the year when the sun reaches its highest point in the sky at noon, marked by the longest and shortest days. There are 2 solstices: Winter and Summer.

Question 4

Equinoxes

Answer 4

Two times of the year where the sun crosses the celestial equator, when day and height are of equal length. This is when the sun shines perpendicular to the equator.

Question 5

Why is there more long-wave radiation in the North than South?

Answer 5

The South has Antartica, so more there is more albedo from the ice sheets and more radiation is reflected

Question 6

Why are there 2 peaks for long wave radiation?

Answer 6

There are desserts at the tropics of Cancer and Capricorn, so there are no clouds and longs of long wave radiation can escape

Question 7

Why is there a dip at around the equator for long wave radiation?

Answer 7

There are lots of rain forests at the equator, so more cloud cover and long wave radiation cannot be emitted and escape.

Question 8

Radiation Balance of the Earth

Answer 8

• Latitude along x-axis - 90 North to 90 South
• Two y-axis, measuring radiation balance in watts / meters squared
• Short-wave solar radiation graph at equator shaped like a mountain - more radiation near equator
• Long-wave Earth radiation higher at the poles, lower near the equator. it has 2 peaks and a dip at equator.
• At equator there is a surplus of radiation
• At poles there are deficits

Question 9

Inter-tropical Convergence Zone

Answer 9

A band few kilometres wide in which winds from the tropics blow inwards, converge and then rise, forming an area of low-pressure

Question 10

Air Pressure

Answer 10

Weight of atmosphere gas pressing down on the Earth’s surface

Question 11

Cold air has high or low pressure

Answer 11

High Pressure

Question 12

Warm air has high or low pressure

Answer 12

Low Pressure

Question 13

Isobar

Answer 13

Lines that show pressure

Question 14

Summer Solstice

Answer 14

The Earth is tilted right. At the summer solstice, the sun shines from the right and shines perpendicular to the tropic of Cancer, so the tropic of Cancer gets the most sunlight. This is during June.

Question 15

Winter Solstice

Answer 15

The Earth is tilted right. At the Winter solstice, the sun shines from the left and shines perpendicular to the tropic of Capricorn, so the tropic of Capricorn gets the most sunlight. This is during December..

Question 16

ITCZ movement

Answer 16

• The ITCZ migrates North in July and South in January due to the tilt and movement of the Earth
• Over the continents, the ITCZ is further in the North because land is heated up more and faster
• Over the oceans, the position of the ITCZ doesn’t change much due to the high specific heat capacity of water (e.g. over the Atlantic Ocean)

Question 17

Coriolis Effect

Answer 17

Any moving body in the Northern Hemisphere deflects to its right. Any moving body in the South Hemisphere deflects to its left.

Question 18

Explaining Variations in Temperature, Pressure and Winds

Answer 18

1) Latitude
2) Distribution of Land and Sea
3) Sea Currents

Question 19

Latitude (explain how it causes variations in temperature, pressure and wind)

Answer 19

Areas that are close to the equator receive more heat than areas that are close to the poles. This is due to two reasons:

1) Insolation is concentrated near the equator but dispersed near the poles.
2) Insolation near the poles has to pass through a greater amount of atmosphere and there is more chance of it being reflected back out to space.

Question 20

Distribution of Land and Sea (explain how it causes variations in temperature, pressure and wind)

Answer 20

This is mainly due to the difference between specific heat capacities of land and ocean.
Water heats more slowly because:
- It is clear, so the sun’s rays penetrate to a greater depth (distributing energy over a larger volume)
- Tides and currents cause the heat to be further distributed
Distance from sea has an important influence on temperature. In winter, in mid-latitudes, sea air is much warmer than the land air, so onshore winds bring heat to the coastal lands. By contrast, during the summer, coastal areas remain much cooler than inland sites.

Question 21

Sea Currents (explain how it causes variations in temperature, pressure and wind)

Answer 21

The effect of ocean currents on temperatures depends upon whether the current is cold or warm. Warm currents from equatorial regions raise the temperatures of polar areas (with the aid of prevailing westerly winds). However, this effect is only noticeable in the winter. For example, the North Atlantic Drift raises the winter temperatures of Northwest Europe.

Question 22

Factors affecting Air movement

Answer 22

1) Pressure and Wind

2) Pressure Gradient

Question 23

Pressure and wind (factor affecting air movement)

Answer 23

The main cause of air motion is the unequal heating of the Earth’s surface. The major equalising factor is the transfer of heat by air movement. Variable heating of the Earth causes variations in pressure and this in turn sets the air in motion. There is thus a basic correlation between winds and pressure

Question 24

Pressure Gradient (factor affecting air movement)

Answer 24

Air blows from high pressure to low pressure. Globally, very high-pressure conditions exist over Asia in Winter (December) due to the low temperatures. By contrast, the mean sea-level pressure is low over continents in summer.

Question 25

Specific Heat Capacity

Answer 25

The amount of heat needed to raise the temperature of a body by 1 degrees celsius

Question 26

Great Conveyer Belt

Answer 26

a constantly moving system of deep-ocean circulation driven by temperature and salinity. The great ocean conveyor moves water around the globe

Question 27

Transfer of Energy around the world

Answer 27

• 80% by wind

- 20% by ocean current

Question 28

North Atlantic Drift Location

Answer 28

Warms up the temperatures at North West Europe