Week 5

Question 1

Equation for incomplete fossil fuel combustion?

Answer 1

Fuel+ oxidiser –> combustion products + heat energy

Question 2

What is combustion completeness related to ?

Answer 2

THe abundance of oxidiser - difficult to achieve but mostly CO2 and H2O

Question 3

Factors that can lead to formation of smog?

Answer 3

• Increased coal burning
• Temperature inversion - layer of warm air over cooler air to trap ground level pollutants
• Stable anticyclonic system- allowing accumulation

Question 4

Ignition of biomass burning - main sources?

Answer 4

10% natural e.g. lightning
90% Human e.g. agricultural, deforestation (savannah, forests)

Question 5

What is Emission Factor (EF) determined byu?

Answer 5

Composition of fuel
Chemical process during combustion

Question 6

Combustion process ?

Answer 6

Ignition –> Flaming and growing and pyrolysis –> Glowing and pyrolysis –> Glowing –> Extinction

Question 7

Plant biomass content?

Answer 7

• Cellulose and hemicellulose
• H2O
• Lignin
• Minerals
• Proteins, amino acid and other metabolites

Question 8

What temperature does smoldering occur?

Answer 8

850K - primarily CO yielded

Question 9

What is the smouldering phase?

Answer 9

Gas-solid phase reaction between O and C in the char layer of the fuel surface producing energy

Question 10

What is an emission ratio in combustion?

Answer 10

Abundance of flaming:smouldering - CO2: sum of all carbon species

Question 11

Emission ratio equation ( gas: reference gas)

Answer 11

= change in gas /change in reference gas

Question 12

Emission factor equation (gas: biomass)

Answer 12

(Mx/Mbiomass) x [C] biomass

Question 13

What does ΔO3/ΔCO represent?

Answer 13

A measure of how much O3 is produced within a plume under the assumption CO is net oxidised before the plume is diffused into general background atmosphere

Question 14

How does the terrestrial biosphere lead to the release of VOCs?

Answer 14

• pyrolysis of vegetation releasing volatiles
• natural release of reactive compounds from growth of plants
• isoprene

Question 15

Potential reasons for release of isoprene?

Answer 15

Thermotolerance- help plant tolerate heat
OXidative Stress protection- reduces damage from O3 and ROS

Question 16

How to take measurements of isoprene?

Answer 16

Flux tower= representing surrounding trees/just a leaf

Question 17

Equation for modelling emissions of isoprene

Answer 17

Emission baseline (Eo) * Adjustment factors * canopy escape parameter

Question 18

Air sea flux equation?

Answer 18

Fx= k (Cw-CaH)

Question 19

What does an increase in warmer temperatures mean for CO2 in oceans ?

Answer 19

Reduction in CO2 dissolved