1. The IPCC Fourth Assessment Report and global climate change
Pete Smith
Royal Society-Wolfson Professor of Soils & Global Change
Institute of Biological & Environmental Sciences
School of Biological Sciences,
University of Aberdeen,
Scotland, UK.
SDC Scotland & Scottish Government - Climate Change Seminar & Evening Reception,
Scottish Parliament, Wednesday 29th October 2008

2. Outline What is the IPCC? Main findings of IPCC on climate
Main findings of IPCC on impacts and adaptation
Main findings of IPCC on mitigation
The political process
Conclusions

3. Outline What is the IPCC? Main findings of IPCC on climate
Main findings of IPCC on impacts and adaptation
Main findings of IPCC on mitigation
The political process
Conclusions

4. What is the IPCC? IPCC : Intergovernmental Panel on Climate Change
Created by World Meteorological Organisation (WMO) & United Nations Environment Programme (UNEP) in 1988
Mandate: assess the science of climate change, impacts and adaptation, mitigation options
Publishes consensus reports (1990, 1996, 2001, 2007) (Cambridge University Press)
Advises Climate Change Convention
Nobel Peace Prize 2007
Website:

5. The three main working groups of IPCC
WGI – Climatology
WGII – Impacts and Adaptation
WGIII – Mitigation
Plus:
Special reports
National Greenhouse Gas Inventories Programme

6. Outline What is the IPCC? Main findings of IPCC on climate
Main findings of IPCC on impacts and adaptation
Main findings of IPCC on mitigation
The political process
Conclusions

7. Humans are responsible for large increases in
atmospheric GHG concentrations in the
atmosphere
Current atmospheric concentrations of carbon dioxide and methane far exceed pre-industrial values determined from ice cores spanning the last 650,000
years. The increases in these greenhouse gases since 1750 are due primarily to emissions from fossil fuel use, agriculture, and land-use changes.
IPCC, AR4, WGI (2007)

8. The 100-year linear trend (1906–2005) is 0.74 [0.56 to 0.92]°C.
Increases in atmospheric GHG concentrations are leading to pronounced global warming
1850
1900
1950
2000
Difference from long term average
The 100-year linear trend (1906–2005) is 0.74 [0.56 to 0.92]°C.
The linear rate of warming averaged over the last 50 years
(0.13 [0.10 to 0.16]°C per decade) is nearly twice that for the
last 100 years showing that global warming is increasing.
IPCC, AR4, WGI (2007)

9. There are different regional trends in temperature increase but they
cannot be explained without human GHG emission increases
IPCC, AR4, WGI (2007)

10. Climate projections without mitigation
IPCC, AR4, WGI (2007)

11. Main findings of IPCC on climate
Warming of the climate system is unequivocal
Very high confidence that net effect of human activities since 1750 = warming
Last 50 years likely to be highest temperature in at least last 1300 yrs
Most of this warming is very likely due to increase in human greenhouse gases
Without emission reduction policies, global temperature could increase by 1.1 to 6.4°C, or even higher in 2100 compared to 1990
Sea level could increase by 18 to 59 cm, or more
Frequency/intensity of several extreme phenomena due to increase (ex: heat waves, droughts, floods, …)
IPCC, AR4, WGI (2007)

12. Outline What is the IPCC? Main findings of IPCC on climate
Main findings of IPCC on impacts and adaptation
Main findings of IPCC on mitigation
The political process
Conclusions

13. The Chacaltaya glacier and ski-lift, Bolivia
Skiing was no longer possible after 2004
IPCC, AR4, WGII (2007)

14. Other effects of regional
climate changes on
natural and human
environments are
emerging, although many
are difficult to discern
due to adaptation and
non-climatic drivers.
IPCC, AR4, WGII (2007)

15. IPCC, AR4, WGII (2007)

16. Main findings of IPCC on impacts and adaptation
Natural systems are being affected by regional climate changes, particularly temperature increases.
Some adaptation is occurring now, but on a limited basis.
Adaptation will be necessary to address impacts resulting from the warming which is already unavoidable due to past emissions.
A wide array of adaptation options is available, but more extensive adaptation than is currently occurring is required to reduce vulnerability to future climate change. There are barriers, limits and costs, but these are not fully understood.
Many impacts can be avoided, reduced or delayed by mitigation.
A portfolio of adaptation and mitigation measures can diminish the risks associated with climate change.
Impacts of climate change will vary regionally but, aggregated and discounted to the present, they are very likely to impose net annual costs which will increase over time as global temperatures increase.
IPCC, AR4, WGII (2007)

17. Outline What is the IPCC? Main findings of IPCC on climate
Main findings of IPCC on impacts and adaptation
Main findings of IPCC on mitigation
The political process
Conclusions

18. GHG emissions have increased by 70% since 1970
Emission trends
GHG emissions have increased by 70% since 1970
IPCC, AR4, WGIII (2007)

19. There is significant mitigation potential at a range of C prices
IPCC, AR4, WGIII (2007)

20. Global economic mitigation potential for
different sectors at different carbon prices
IPCC, AR4, WGIII (2007)

21. The cost of stabilizing atmospheric GHG concentrations by 2100
increases with the stringency of the stabilization target
Stabilizing at ppm CO2-eq. will cost -0.6 to1.23% of GDP
Stabilizing at ppm CO2-eq. will cost 0.2 to 2.5% of GDP
Stabilizing at ppm CO2-eq. will cost 3% of GDP
IPCC, AR4, WGIII (2007)

22. Main findings of IPCC on mitigation
A significant proportion of GHG emissions can be mitigated at relatively low cost by 2030
There is significant mitigation potential in all sectors (industry, energy, buildings, transport, agriculture, forestry and waste)
Lower atmospheric GHG stabilization levels will cost more
In order to stabilize the concentration of GHGs in the atmosphere, emissions would need to peak and decline thereafter. The lower the stabilization level, the more quickly this peak and decline would need to occur.
Mitigation efforts over the next two to three decades will have a large impact on opportunities to achieve lower stabilization levels

23. Outline What is the IPCC? Main findings of IPCC on climate
Main findings of IPCC on impacts and adaptation
Main findings of IPCC on mitigation
The political process
Conclusions

24. The Political Process
UNFCCC (United Nations Framework Convention on Climate Change - since 1992)
COP (Conference of Parties)
Kyoto Protocol to the UNFCCC ( ) – only developed countries – significant not ratification by e.g. US, Australia
Bali Roadmap (what will come after 2012) – will include developing countries as well as (hopefully) non-Kyoto developed countries

25. Talks under the Kyoto Protocol
United Nations Framework Convention on Climate Change
Talks under the Kyoto Protocol
1st commitment period expires in 2012
AWG-KP: to negotiate further commitments for Annex I Parties for the period beyond 2012
Analysis of mitigation potential for different sectors: policies, measures and technologies
Analysis of means to reach emission reduction targets and identification of ways to enhance their effectiveness and contribution to sustainable development
Slide courtesy of Fernando Castellanos Silveira, UNFCCC

26. United Nations Framework Convention on Climate Change
The Bali Action Plan
Two-year negotiation process for a broad response to climate change.
Key elements:
Shared vision
Mitigation
Adaptation
Finance
Technology.
Slide courtesy of Fernando Castellanos Silveira, UNFCCC

27. United Nations Framework Convention on Climate Change
The Bali Action Plan
Slide courtesy of Fernando Castellanos Silveira, UNFCCC

28. Elements of the Bali Action Plan
United Nations Framework Convention on Climate Change
Elements of the Bali Action Plan
Action by developed countries
Measurable, reportable, verifiable mitigation action/commitments
Implementation of action on adaptation
Support action by developing countries
Action by developing countries
Nationally appropriate mitigation actions supported and enabled by technology, financing and capacity building
Reducing emissions from deforestation
Implementation of action on adaptation
Cooperative sectoral approaches and
sector-specific actions on mitigation
Slide courtesy of Fernando Castellanos Silveira, UNFCCC

29. There is a need for both adaptation and mitigation
United Nations Framework Convention on Climate Change
It is necessary to have a comprehensive, long-term climate change strategy
There is a need for both adaptation and mitigation
The less we mitigate now, the more we will need adaptation later – and more resources will be needed.
There are many challenges but also many opportunities
The poorest countries are the most vulnerable and will be the most affected by climate change
Slide courtesy of Fernando Castellanos Silveira, UNFCCC

30. Outline What is the IPCC? Main findings of IPCC on climate
Main findings of IPCC on impacts and adaptation
Main findings of IPCC on mitigation
Climate change in Scotland over the next century
Conclusions

31. John Holdren, President of the American Association for the Advancement of Science
‘We basically have three choices –mitigation, adaptation, and suffering.
We’re going to do some of each. The question is what the mix is going to be.
The more mitigation we do, the less adaptation will be required, and the less suffering there will be.’
Slide courtesy of Jean-Pascal van Ypersele

32. Conclusions
Climate change is real, human induced and is changing ever more rapidly
Adaptation will cost money, but not as much as the cost of the damage caused by climate change. Some will be necessary due to climate change already “in the pipeline”
Mitigation is possible and a significant proportion can be met by low cost options. Mitigation reduces the amount of adaptation necessary
The problem is enormous, but there is hope that we can deal with it. Drastic emission reduction targets are necessary (e.g. 80% reduction by 2050) – these will be difficult to achieve and creative, sustainable solutions in all sectors will be needed.

33. Thank you for your attention