vertical layering in the atmosphere

Question 1

the atmosphere may be…

Answer 1

divided into a number of layers due to temperature and zones of temperature change

Question 2

due to gravity and compression..

Answer 2

most of the atmosphere is concentrated near the earth’s surface; about 50% lies within 5.6km of the surface, and 99% within 40km.
- most of our climate and weather processes operate within 16-17km of the surface

Question 3

troposphere

Answer 3

• extends to approx 12km above the earth’s surface and temperatures decrease upwards to -45°C
• unstable layer as heat will still rise
• all our weather and climate are contained in this layer, including all its water vapour and dust particles
• 75% of the atmospheric pressure is here

Question 4

global energy balance

Answer 4

the earth gets its energy from the sun and loses it to space
some places get more energy than others, but as a whole the earth’s temperatures more or less stays the same from year to year
therefore, there must be a balance between inputs and outputs and that the energy must be evened out between these places
(see diagram)

Question 5

energy from the sun..

Answer 5

is received by the earth/atmosphere, this is called insolation

Question 6

insolation

Answer 6

the amount of solar radiation reaching a given area

Question 7

insolation mainly consists of..

Answer 7

short-wave radiation. some is absorbed and some is reflected and around 50% reaches the earth’s surface.
this energy heats the surface, and then emits low-wave energy back into the atmosphere, where it is absorbed by gases in the air
(the atmosphere is not directly heated from the sun, but indirectly by the earth’s surface from below

Question 8

the albedo effect

Answer 8

cloud and dust particles in the atmosphere both absorb and reflect energy
the reflective index of the clouds and the earth’s surface is known as the albedo, and it is expressed as a % of incoming radiation that is reflected
(see diagram)

Question 9

the response of the earth-atmosphere system to solar insolation

Answer 9

overall, there must be a balance between inputs and outputs or the world would either be heating up or cooling down
- on average 68% of the solar insolation is absorbed by the earth-atmosphere system
- the other 32% is reflected back to space from clouds, dust and the surface.
- albedo is the reflective index of the surface
- insolation is solar energy short waves of light and heat

Question 10

the loss of energy absorbed by the earth-atmosphere system

Answer 10

the energy absorbed is returned to space either:
1. directly by the radiation window
2. by transfer to the atmosphere by
a) long wave radiation b) latent heat c) convection
how surfaces such as the sun emit radiation as short waves, whereas cooler surfaces, such as earth, emit long wave radiation
most gases are unable to absorb short wave radiation but can absorb long wave
this is why the atmosphere is not heated directly by the sun but rather by the earth below

Question 11

latent heat

Answer 11

energy stored when water changes from a liquid to a gas (eg process of evaporation)

Question 12

convection

Answer 12

transfer of energy by rising currents of warm air
in order to maintain a balance, all 68% of incoming solar energy must return to space as shown in the diagram