C9 The Atmosphere

Question 1

Proportions of gases in the air

Answer 1

Argon 1%
CO2 0.04%
Oxygen approx. 20%
Nitrogen approx. 80%

Question 2

The earths early atmosphere

Answer 2

Theories developed 4.6 billion years ago
1. Theory= volcanic activity released gases
Volcanos produce nitrogen, methane, ammonia, water vapour
Water vapour condenses to form oceans
CO2 dissolve into water and carbonates precipitated forming sediments. Reducing CO2 levels in atmosphere

Question 3

Evidence of the theories

Answer 3

Measuring carbon and boron isotope ratios in sediments under the sea
Composition of gases given out by volcanoes

Question 4

Evaluating the theories

Answer 4

Evidence is limited as time scale of 4.6 billion years

No direct measurements can be made

Question 5

Proxy evidence

Answer 5

Evidence from one source gathered from ancient times that can be used to make an assumption about another related ancient effect

Question 6

Evidence from direct measurements

Answer 6

More valuable
Measurements may be taken incorrectly
Needs to be repeatable to make it reliable

Question 7

Early production of oxygen

Answer 7

First life forms appeared 3.5 billion years ago (could only respire anaerobically)
Algae produced oxygen 2.7 billion years ago
As organisms developed oxygen levels rose

Question 8

Photosynthesis balanced equation

Answer 8

6CO2 + 6H2O = C6H12O6 + 6O2

Question 9

The great oxygenation event

Answer 9

Oxygen produced as a waste product was removed by the oxidation of iron to form iron(III) oxide.
(Iron oxide sediment formed)

Question 10

Trapping carbon dioxide

Answer 10

Plants died and decayed and then compressed to form peat, eventually becoming coal.

Question 11

What is coal?

Answer 11

Thick plant deposits
Carbon locked in the ground
Reduced CO2 levels

Question 12

What formed crude oil and natural gas?

Answer 12

Animal deposits

Plankton

Question 13

Forming limestone

Answer 13

Made from calcium carbonate

From shells and skeletons under high pressure

Question 14

Evidence for CO2 levels

Answer 14

Look at ice cores
Results can be plotted 800000 years
Proxy evidence such as counting stomata

Question 15

Greenhouse gases

Answer 15

Trap radiation from the sun to help keep the earth relatively warm

Question 16

Green house effect

Answer 16

1. Light from the sun is changed into thermal energy when it reaches the earth (short wavelength)
2. Some of the heat energy is reflected from the earth (long wavelength is harder to escape atmosphere)
3. Some energy is trapped because of a thicker atmosphere
4. This continues

Question 17

What radiation is involved

Answer 17

UV Ray’s from the sun

Infrared radiation is reflected

Question 18

9.6

Answer 18

Human activities

Question 19

Human affect green houses gases

Answer 19

CO2- combustion of ff and deforestation

Methane- more animal farming and decomposition of rubbing in landfill sites

Question 20

Modelling climate change

Answer 20

Very difficult to do
Has to be peer reviewed
Models are simplified when presented to the public

Question 21

Effects of global climate change

Answer 21

Rising sea levels- flooding and erosion
More frequent and severe storms
Changes in the amount, timing, and distribution of rainfall

Question 22

Environmental concerns of climate change

Answer 22

Temperature stress for humans and wildlife
Water stress for h&w
Changes in the food producing capacity of some regions
Changes to the distribution of wildlife species
Glaciers melting

Question 23

Carbon footprint

Answer 23

The total amount of carbon dioxide and other greenhouse gases emitted over the full cycle of a product, service or event

Question 24

Actions to reduce our personal carbon footprint

Answer 24

Increase use of alternate energy sources and H fuel cells
Energy conservation and energy efficiency in our homes
Energy efficiency by driving cars that use less fuel

Question 25

Governments reducing the carbon footprint

Answer 25

Carbon capture
Carbon taxes and licenses
Carbon off setting
Carbon neutrality

Question 26

Because the population has risen methane levels rise from

Answer 26

Grazing more animals
More wet cultivation for rice growing
More rubbish landfill sites have opened

Question 27

Trying to reduce the carbon footprint

Answer 27

Lifestyle changes needed

More public information and education needed

Question 28

Other problems in reduction

Answer 28

Scientific disagreements
Economic considerations
Incomplete international cooperation

Question 29

Common atmospheric pollutants

Answer 29

Sulfur dioxide
Carbon monoxide
Nitrogen monoxide

Question 30

Carbon monoxide (CO)

Answer 30

Caused- incomplete combustion in a shortage of oxygen

Reduced- converted to CO2 in a catalytic converter

Question 31

Sulfur dioxide (SO2)

Answer 31

Caused- burning coal or petrol containing sulfur in oxygen

Reduced- removed from power stations by capturing with limestone

Question 32

Oxides of nitrogen (NOx)

Answer 32

Caused- from N2 and O2 at very high temperatures such as in an engine
Reduced- converted to N2 by a catalytic converter

Question 33

Pollution by particulates

Answer 33

Solid particles and unturned hydrocarbons form particulate matter (PM) in the atmosphere
Diameter of less than 10 micrometeres (PM10) can get past filters and into lungs
PM2.5 can penetrate alveoli. Need to be reduced as cause respiratory problems

Question 34

Toxic gases

Answer 34

Carbon monoxide
Combines with haemoglobin
Reduces capacity of the blood to carry oxygen

Question 35

Acid rain

Answer 35

Burning coal makes carbon dioxide and sulfur dioxide
Dissolves in water to make acid rain
Damaging plants and buildings
Sulfur dioxide and oxides of nitrogen cause respiratory problems in humans (smog)

Question 36

Particulates

Answer 36

Global dimming- reduce amount of sunlight the earth surface receives
Damage to the lungs