Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 1Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 1

A Short Overview of the IPCC Report on

Climate Change Mitigation 2007 (WG III)

Prof. Dr. Olav Hohmeyer

Universität Flensburg

Vice Chair WG III IPCC

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 2Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 2

Structure of the presentation

• Anthropogenic climate change• New results on climate change in 2007

(WG I)• New results on climate change mitigation

2007 (WG III):– The need for mitigation– The timeframe for mitigation– The means for mitigation– The cost of mitigation

• Mitigation and innovation• Conclusions

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 3Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 3

Anthropogenic climate change

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 4Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 4

The greenhouse effect

JTH 17-07-2001 12 COP6bis/SBSTA

The Greenhouse Effect

Solar radiation

Long-wave radiation

Source: Houghton 2001

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 5Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 5

Source: IPCC 2007a (WG I, SPM, p. 3)

Anthropogenic Influences on Climate Change

CO2, CH4 and N2O Concentrations

- far exceed pre-industrial values- increased markedly since 1750 due to human activities

Relatively little variation beforethe industrial era

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 6Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 6

New results on climate change in 2007 (WG I)

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 7Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 7

CO2

CH4

Long term changes in THG concentrations

The atmospheric concentration of CO2 and CH4 in 2005 exceeds by far the natural range of the last 650,000 years

Source: Pachauri und Jallow, 6.2.2007

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 8Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 8

Global GHG emissions 1970 - 2004

Source: IPCC 2007 (TS WG III, p. 4)

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 9Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 9

Structure of global GHG emissions in 2004

Source: IPCC 2007 (TS WG III, p. 4)

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 10Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 10

Regional distribution of per capita GHG emissions in 2004

Source: IPCC 2007 (TS WG III, p. 8)

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 11Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 11

Increased global temperature change

Source: IPCC 2007a (WG I TS p, 37)

Wärmste 12 Jahre seit 1850:1998,2005,2003,2002,2004,20

06, 2001,1997,1995,1999,1990,20

00

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 12Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 12

Different Scales

Arctic vs Global annual temperature anomalies (°C)

Source: Pachauri und Jallow, 6.2.2007

Warming in the Arctic is double that for the globe from 19th to 21st century and from late 1960s to present.

Warmth 1925 to 1950 in Arctic was not as widespread as recent global warmth.

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 13Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 13

Source: IPCC 2007a (WG I TSp.62)

Anthropogenic and natural forcings

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 14Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 14

Components of radiative forcingComponents of radiative forcing

Source: IPCC 2007a (WG I, SPM p.4)

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 15Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 15

New results on climate change mitigation 2007:• The need for mitigation

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 16Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 16

Source: IPCC 2007a (WG I, SPM p.14)

Projections of Future Changes in Climate

Best estimate for low scenario (B1) is 1.8°C (likely range is 1.1°C to 2.9°C), and for high scenario (A1FI) is 4.0°C (likely range is 2.4°C to 6.4°C).

Broadly consistent with span quoted for SRES in TAR, but not directly comparable

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 17Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 17

New results on climate change mitigation 2007:• The timeframe for mitigation

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 18Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 18

New stabilization scenarios

Source: IPCC 2007 (TS WG III, p. 19)

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 19Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 19

Emissions for stabilization levels of 445 – 570ppmv CO2eq.

Source: IPCC 2007 (SPM WG III, p. 23)

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 20Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 20

Arctic ice loss faster than forecast by AR4

Quelle: Stroeve et al. 2007 S.2

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 21Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 21

New results on climate change mitigation 2007:• The means for mitigation

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 22Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 22

Global economic mitigation potential 2030

Source: IPCC 2007 (SPM WG III, p. 11)

Source: IPCC 2007 (SPM WG III, p. 10)

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 23Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 23

Global sectoral economic mitigation potential 2030

Quelle: IPCC 2007 (SPM WG III, p. 14)

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 24Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 24

Contributions to cumulated emission reductions until 2030 and 2100 - 650 and 490-550ppmv CO2-eq

Source: IPCC 2007 (SPM WG III, S. p5)

Prof. Dr. Olav Hohmeyer:

IPAC: Policy Assessment Model for China

IMAGE: Integrated Model of Global Climate Change (RIMV)

MESSAGE: IIASA integrated modelling framework

AIM: Asian-Pacific Integrated Model

Prof. Dr. Olav Hohmeyer:

IPAC: Policy Assessment Model for China

IMAGE: Integrated Model of Global Climate Change (RIMV)

MESSAGE: IIASA integrated modelling framework

AIM: Asian-Pacific Integrated Model

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 25Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 25

Mitigation potential in the energy sector by 2030

Source: IPCC 2007 (SPM WG III, p. 17)

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 26Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 26

Mitigation potential in the energy sector by 2030

Source: IPCC 2007 (SPM WG III, p. 17/18)

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 27Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 27

New results on climate change mitigation 2007:• The cost of mitigation

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 28Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 28

Global macro-economic mitigation costs for 2030 and 2050

source: IPCC 2007 (SPM WG III, p. 15)

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 29Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 29

Global macro-economic mitigation costs for 2030 and 2050

Source: IPCC 2007 (SPM WG III, p. 26)

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 30Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 30

Mitigation and innovation

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 31Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 31

Technology development, innovation and mitigation

Source: IPCC 2007 (SPM WG III, p. 24)

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 32Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 32

Conclusions

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 33Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 33

Conclusions

• Climate change is developing faster than we thought

• GHG concentrations need to be stabilized at even lower levels (455 – 490 ppmvCO2eq) to avoid serious damages

•

• The necessary mitigation technologies are available

• Mitigations costs need to be further reduced

• Mitigation will be cheaper than thought before

• Innovation will play a crucial role in cost reductions

Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 34Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 34

Thank you for your attention!