emission reductions for stabilizing at 450 ppm...

Emission reductions for stabilizing at 450 ppm CO2-eq

AWG LCA Technical BriefingBonn, Germany, 30.3.2009

Niklas Höhne, [email protected], Ecofys, GermanyMichel den Elzen, PBL, The Netherlands

Box 13.7

Source: IPCC Fourth Assessment Report, Working Group III, Box 13.7

Content

• “Reductions of greenhouse gas emissions in Annex I and non-Annex I countries for meeting concentration stabilisation targets”den Elzen and HöhneClimatic Change (2008) 91:249–274

1. Assessment of available studies (as for IPCC AR4)

2. Sensitivity of the impact of major determinants using one model

Comparison

• 16 studies used and quoted in the IPCC analysis (box 13.7)

• 2 additional studies from 2003

• 7 new studies available after the IPCC AR4

All studies use different

• Baselines

• Effort sharing principles

• Global emission levels in 2020 for the same GHG concentration level

• Treatment of deforestation (usually excluded – assumed to develop similarly)

Annex I450 ppm CO2eq.

Source: den Elzen and Höhne 2008, “Reductions of greenhouse gas emissions in Annex I and non-Annex I countries for meeting concentration stabilisation targets”, Climatic Change (2008) 91:249–274

-25% to -40%below 1990 level in 2020

Non-Annex I 450 ppm CO2e


-15% to -30%below baseline in 2020

Developing country emissions

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

1990 1995 2000 2005 2010 2015 2020

MtC

O2eq

Range of baseline scenarios

Developing country emissions

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

1990 1995 2000 2005 2010 2015 2020

MtC

O2eq

Range of baseline scenarios

15-30% below baseline

Necessary change in 2020

• Non-Annex I: 10% above to 10% below baseline

0% to –25%below 1990

C-650 ppm CO2-eq

• Deviation from baseline in Latin America and Middle East, East Asia

• Non-Annex I: 0% to -20% below baseline

–10% to –30% below 1990

B-550 ppm CO2-eq

• Substantial deviation from baseline in Latin America, Middle East, East Asia and Centrally-Planned Asia

• Non-Annex I: -15% to -30% below baseline

–25% to –40% below 1990

A-450 ppm CO2-eq

Non-Annex I Annex IScenario category

Source: IPCC Fourth Assessment Report, Working Group III, Box 13.7 and Den Elzen, Höhne: “Reductions of greenhouse gas emissions in Annex I and non-Annex I countries for meeting concentration stabilisation targets”, Climatic Change

Content

• “Reductions of greenhouse gas emissions in Annex I and non-Annex I countries for meeting concentration stabilisation targets”den Elzen and HöhneClimatic Change (2008) 91:249–274

1. Assessment of available studies (as for IPCC AR4)

2. Sensitivity of the impact of major determinants using one model

-10%

-40%

Annex I and Non-Annex I reductions


-80%

-60%

-20%

0%

20%

40%

-30%-25%-20%-15%-5%0%

non-Annex I reduction from baseline in 2020

Ann

ex I

redu

ctio

n re

lativ

e to

199

0

450 ppm CO2eq



-80%

-60%

-40%

-20%

0%

20%

40%

-30%-25%-20%-15%-10%-5%0%


Ann

ex I

redu

ctio

n re

lativ

e to

199

0

450 ppm CO2eq550 ppm CO2eq650 ppm CO2eq

Impact of different baselines


-80%

-60%

-40%

-20%

0%

20%

40%

-30%-25%-20%-15%-10%-5%0%


Ann

ex I

redu

ctio

n re

lativ

e to

199

0

IPCC-SRES Average (default)IPCC-SRES MinimumIPCC-SRES Maximum

450 ppm CO2 eq

(a)

Conclusions• IPCC:

• -25% to -40% and “substantial deviation from baseline”

• Den Elzen & Höhne (same authors, same and additional data):

• “substantial deviation from baseline” would be -15% to -30% below baseline for the group of Non-Annex I countries

• still an absolute increase above today’s level

• Major determinants covered in these ranges for 2020

• Baseline• Effort sharing principles• Global emission level in 2020 leading stabilization of

concentrations• Treatment of deforestation

Backup slides

Changing emissions

Annex I Non-Annex I

1990 2020

-25 to -40%below 1990

1990 2020

-15 to -30%below baseline

Data source: IPCC AR4 WG3, box 13.7 and den Elzen and Höhne 2008, “Reductions of greenhouse gas emissions in Annex I and non-Annex I countries for meeting concentration stabilisation targets”, Climatic Change (2008) 91:249–274

With/without trading – no double counting

Annex I Non-Annex I

1990 2020

-25 to -40%below 1990

1990 2020

-15 to -30%below reference

Data source: IPCC AR4 WG3, box 13.7 and den Elzen and Höhne 2008, “Reductions of greenhouse gas emissions in Annex I and non-Annex I countries for meeting concentration stabilisation targets”, Climatic Change (2008) 91:249–274

Use of trading

Use of trading

Impact of different baselines


Impact of different global emission levels


Impact of deforestation assumptions


Factors influencing the -15% to -30% below BAU

Reduction of the non-Annex I compared to the baseline

-35-30-25-20-15-10-50

Halt deforestation

Global emissionslimit in 2020

Annex I reductionin 2020

Baseline

default

+30%

2.5

Max: >4.1°C

A1fB1

Update B2

-40% -25%

+15%

2020

2030

Sheenan

Annex I : -30% below 1990

450 ppm CO2eq


emission reductions for stabilizing at 450 ppm...

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