Global Issues Part 1

Question 1

List three UN bodies which affect the way in which you work?

Answer 1

• The World Health Organisation
• United Nations Environmental Programme
• International Maritime Organisation

Question 2

What is the work of WHO?

Answer 2

Sets environmental and air quality standards and even eradicates disease

Question 3

What is the work of UNEP?

Answer 3

It leads on global treaties that aim at protecting the environment

Question 4

What is the work of the IMO?

Answer 4

It regulates shipping and also dumping in international waters

Question 5

What does OSPAR stand for?

Answer 5

Oil Spill Prevention, Administration and Regulation

Question 6

What is the main aim of OSPAR?

Answer 6

It is involved in the management of produced water from offshore installations

Question 7

What regulation did OSPAR lead to?

Answer 7

Offshore Petroleum Activities (Oil Pollution Prevention and Control) Regulations 2005

Question 8

What does the Offshore Petroleum Activities Regulations 2005 lead to?

Answer 8

• Permits required for discharging ‘produced waters’ into the sea
• Limits for discharges in water of oil and some pollutants (Benzene, Toluene, Ethyl Benzene)
• Every offshore platform has to ensure no more than 30 mg/L monthly average dispersed oil in water discharge

Question 9

How can overall reduction in discharges of pollutants be achieved?

Answer 9

• Reducing the volume of water

- Reducing the concentration in the produced water

Question 10

The Offshore Petroleum Activities Regulations also enforce the use of Best Available Techniques (BATs) and Best Environmental Practices (BEPs) what are these?

Answer 10

• latest state of the art processes to indicate the practical suitability of a particular measure for limiting discharges, emissions and waste- the application of the most appropriate combination of environmental control measures and strategies

Question 11

What is the chemical formula for ozone?

Answer 11

O3

Question 12

What is the purpose of ozone at low altitudes?

Answer 12

It is a pollutant

Question 13

What is the purpose of ozone at high altitudes?

Answer 13

It absorbs harmful UV rays from the sun while releasing heat as a result. It is responsible for the creation of the stratosphere.

Question 14

What is the split of ozone between low altitudes and high altitudes?

Answer 14

1:9

Question 15

What is the stratosphere?

Answer 15

It is the atmospheric layer where temperatures rise with altitude.

Question 16

What wavelengths of light are forming ozone?

Answer 16

Any wavelengths below 240 nm

Question 17

What are the stages of forming ozone?

Answer 17

• UV light breaks apart the bond in 02 to form 2 x O* radicals.
• The reaction between O* and O2 to form O3

Question 18

Which reactions are then destroying the ozone>

Answer 18

• Absorption of UV radiation with wavelengths less than 315 nm.
• Reaction with OH * or NO *

Question 19

How do we measure the amount of ozone in the atmosphere?

Answer 19

100 Dobson Units (DU) corresponds to a 1 mm thick layer of pure ozone that would have been brought back to STP (1 atm, 0 oC) on the ground from the whole atmospheric column above a given location at the surface at the Earth.

Question 20

Where is the ‘ozone hole’?

Answer 20

The ozone hole is above Antarctica

Question 21

Why is it classed as an ‘ozone hole’?

Answer 21

The concentration of ozone has been well below 220 DU (the boundary value for a ‘hole’) since 1978

Question 22

Which substances are primarily responsible for the depletion of ozone in the stratosphere?

Answer 22

Cl* radicals

Also Br* radicals but these are much less effective and less abundant

Question 23

From which molecules are the Cl* radicals formed?

Answer 23

Substances that are stable enough to reach the stratosphere intact - especially CFCs

Question 24

What are the reactions by which Cl* is able to catalyse ozone destruction?

Answer 24

• Cl* + O2 —> ClO + O2

- ClO + O3 —> Cl * + 2O2

Question 25

What is the turn-over-number for the reaction?

Answer 25

It is over 100,000 over an average of 2 years before chlorine is taken away from the stratosphere

Question 26

Why is there a seasonal effect for ozone depletion?

Answer 26

The synthesis of ozone needs sunlight and sunlight is also needed for the generation of fresh Cl* radicals that destroy it. There is no sunlight at the poles during winter. Depletion picks up significantly at the end of winter when sunlight arrives.

Question 27

What happens during winter?

Answer 27

There are long polar winter nights in which the temperature of the stratosphere plummets and there is the formation of stratospheric polar clouds. These polar clouds store reservoir species such as HCl and ClONO2.

Question 28

What happens during spring?

Answer 28

Spring exposes these clouds to UV light, unleashing Cl* that destroy the ozone.

Question 29

Why is cooling amplified in the Antarctica?

Answer 29

• There is the presence of land unlike in the Arctic (water is responsible for storing heat)
• Isolation of the air by a stable vortex circling the continent

Question 30

What is the importance of the ‘hole’ expanding?

Answer 30

It is a public health concern over the high potential for harmful UVs (skin cancer is fatal).

Question 31

What were chlorofluorocarbons (CFCs) used for?

Answer 31

They were used as the working fluid in refrigerant cycles, aerosol propellants, fire extinguishing agents.

Question 32

What was the main result of the Montreal Protocol?

Answer 32

The phasing out and banning of chlorofluorocarbons (CFCs)

Question 33

Why were chlorofluorcarbons such a problem?

Answer 33

Because they were the main contributor of ozone depletion. And their benign properties such as being non-toxic, non-flammable, stable only contributed to the problem.

Question 34

What are the two replacements for chlorofluorocarbons (CFCs)?

Answer 34

• Hydrochlorofluorocarbons (HCFCs)

- Hydrofluorocarbons (HFCs)

Question 35

Describe the use of hydrochlorofluorocarbons as a replacement for CFCs?

Answer 35

They are supposed to be an interim solution between 2020 - 2030. They still contain chlorine and they contain one more hydrogen which makes the molecule less stable and then less likely to reach the stratosphere. They are supposed to be limited to the developing countries and their lack of stability limits their usefulness

Question 36

Describe the use of hydrofluorocarbons as a replacement for CFCs?

Answer 36

They contain no chlorine and therefore they are not ozone depleting. They can be used in developed countries. But they are expensive and their properties are not ideal. They are poor solvents for refrigerant lubricants and they are also incredibly expensive.

Question 37

What is the major downfall of hydrofluorocarbons?

Answer 37

Their global warming potential is 1000 times greater than that of CO2 and their concentration in air is steadily rising.

Question 38

What is the Kigali amendment of the Montreal protocol?

Answer 38

Due to their global warming potential, HFCs are being phased down.

Question 39

What about returning to traditional refrigerants?

Answer 39

Traditional refrigerants such as ammonia, sulphur dioxide, hydrocarbons. All of these are ore difficult to use (toxic, corrosive, flammable) and require better-sealed units with lower inventories.

Question 40

What about using CO2 as a refrigerant?

Answer 40

CO2 can be an acceptable refrigerant and it is inert although working pressures is a little high. It is not the cheapest option.

Question 41

What about hydrofluoroolefines?

Answer 41

They have shown suitable properties and modest GWPs, however environmental pressure groups are concerned about their widespread use due to a perceived uncertainty on the fate of their degradation products in the environment.

Question 42

What is the effectiveness of the Montreal protocol?

Answer 42

The CFC concentrations in the air are decreasing but the concentrations of HCFC are increasing. The rate of increase of ozone depletion has decreased but the size of the annular polar hole has not yet peaked.