Lecture on greenhouse gas emission scenarios and technical options for emission reduction to postgraduate students of economics. Covers Chapter 2 of Climate Economics textbook.

1. Climate Change Scenarios
• The problem:
– Sources
– Mechanisms
– Possible futures
– Consequences

3. CH4
20%
N2O
8%
HFC
1%
PFC
0%SF6
0%
CO2 Power & heat
32%
CO2 Manufacturing
14%
CO2 Other
2%
CO2 Residential
8%
CO2 Transport
15%

4. Sources of greenhouse gas emissions
• Carbon dioxide
– Combustion of fossil fuels
• Peat 117, Coal 95, Petrol 70, Gas 57 tCO2/TJ
– Land use change
– Cement production
• Methane
– Ruminants
– Paddy rice
– Waste
– Leakage
• Nitrous oxide
– Agriculture
• Other gases
– Specialised industry

5. Emission trends
• Kaya identity 
Y X E
E P
P Y X

7. Emission scenarios
• Kaya identity
• So, we need to predict how many people
there will be in the future, how rich they
will be, how much energy they will use, and
what sort of energy; how much waste they
will generate and how they will dispose of
it; and what they will eat and where that
food will be grown
• And over a period of 100 years or more
• Scenario uncertainty is compounded by
uncertainty over climate and carbon cycle

Y X E
E P
P Y X

8. 0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
2.75
3.00
1970 1980 1990 2000 2010 2020 2030 2040 2050 2060 2070 2080 2090 2100
0
2
4
6
8
10
12
14
16
18
20
1970 1980 1990 2000 2010 2020 2030 2040 2050 2060 2070 2080 2090 2100
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1970 1980 1990 2000 2010 2020 2030 2040 2050 2060 2070 2080 2090 2100
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1970 1980 1990 2000 2010 2020 2030 2040 2050 2060 2070 2080 2090 2100

9. 0 50 100 150 200 250 300 350
Bituminous coal
Sub-bituminous
coal
Lignite
Crude oil and
natural gas liquids
Oil shale
Bitumen
Extra-heavy oil
Natural gas
Shale gas
parts per million by volume
Reserves Proved Probable Possible