Topic 6 - Atmospheric systems and society

Question 1

What is the composition of atmosphere broken down as (in %) - oxygen, nitrogen, other gases?

Answer 1

Nitrogen - 78%
Oxygen - 21%
Other (carbon dioxide, argon, water vapour, ozone) - 1%

Question 2

Stratosphere height

Answer 2

10-50km high

Question 3

Troposphere height

Answer 3

Less then 10km

Question 4

Greenhouse effect

Answer 4

Natural phenomenon maintaining temperatures for living systems. Gases in the atmosphere reduce heat loss by radiation back into space. Trap heat energy and re-radiate it, some back to space and some back to earth

Question 5

Ozone Depleting Substances (ODS)

Answer 5

Include CFCs are used in aerosols, gas blown plastics, pesticides, flame retardants and refrigerants

Question 6

UV radiation impact on humans

Answer 6

-VE Reaching earth surface damages human living tissue, increasing incidents of cataracts, mutation during cell division, skin cancer, suppression of immune system
+VE Stimulates production of Vitamin D, can be used to treat psoriasis and vitiligo (skin diseases), industrial uses in lasers, used as a steriliser as it kills pathogenic bacteria

Question 7

UV radiation impact on biological productivity

Answer 7

Damage to photosynthetic organisms, especially phytoplankton

Question 8

UNEP - United Nations Environment Programme

Answer 8

Played a key role in providing information and creating and evaluating international agreements for the protection of stratospheric ozone

Question 9

Montreal Protocol

Answer 9

1987 + yearly updates including Kigali Amendment 2016. International agreement, 197 countries agreed, including USA, China, Russia.
Reduction of use of ODS.
Multilateral fund set up to support nations in their transition away from ODS such as CFC
Staggered time frame to support poorer nations and their transition

Question 10

Ozone layer

Answer 10

Dynamic layer at 20-40km high where ozone is continuously made from oxygen atoms and is continuously converted back to oxygen. During both processes UV radiation is absorbed (good thing)

Question 11

Primary pollutants

Answer 11

From combustion of fossil fuels, include carbon monoxide, carbon dioxide, black carbon / soot, unburned hydrocarbons, nitrogen oxides and sulfur oxides

Question 12

Secondary pollutants

Answer 12

Formed when primary pollutants react with other chemicals already in the atmosphere

Question 13

Tropospheric ozone

Answer 13

Example of secondary pollutant formed when oxygen molecules react with oxygen atoms that are released from nitrogen dioxide in the presence of sunlight

Question 14

Smog

Answer 14

Complex mixture of primary and secondary pollutants

Question 15

Thermal inversions

Answer 15

Occur due to a lack of air movement when a layer of dense, cool air is trapped beneath a layer of less dense warm air. Causes concentration of air pollutants to build up near the ground rather than being dispersed

Question 16

Tropospheric ozone impacts

Answer 16

-VE
Damage to plants, ozone degrades chlorophyll so photosynthesis and therefore productivity is reduced
- Damage to humans. Can impact lungs leading to respiratory illness. Eye, nose and throat irritation
- Damage to materials and products. Ozone attacks natural rubber, reducing life time of car tyres. Bleaches fabric

Question 17

Photochemical smog

Answer 17

Formed when ozone, nitrous oxides and gaseous hydrocarbons (oil/gas) from vehicle exhausts interact with strong sunlight

Question 18

Acid deposition

Answer 18

Term for acid coming down from the air. Often comes down in the form of rain (wet deposition) or ash (dry deposition)

Question 19

Effects of acid deposition

Answer 19

Direct effects
- weakening tree growth in coniferous forests
- acid falling in lakes and ponds decreases ph of the water

Indirect effects
- toxic effects. Increase solubility of metal ions such as aluminium in soil, which is toxic to plants and fish
- nutrients more easily leached through soil

Buildings - limestone buildings react with acid rain and dissolve
Peat bogs +VE they produce 40% less methane (GHG)
Human health - can affect lungs, leads to premature deaths

Question 20

Reducing effects of acid deposition

Answer 20

Liming lakes to neutralise activity
Reduce emissions
Add waste gas scrubbers to collect pollutants in electricity production.
Use catalytic converters in cars to remove nitrogen oxides