The IPCC Fourth Assessment Report and global climate change

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. E-mail: pete.smith@abdn.ac.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: www.ipcc.ch

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. Difference from 1961-1990 long term average 1850 1900 1950 2000 Increases in atmospheric GHG concentrations are leading to pronounced global warming 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. 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 590-710 ppm CO2-eq. will cost -0.6 to1.23% of GDP Stabilizing at 535-590 ppm CO2-eq. will cost 0.2 to 2.5% of GDP Stabilizing at 445-535 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 (2008-2012) – 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. 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. 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 United Nations Framework Convention on Climate Change Elements of the Bali Action Plan Cooperative sectoral approaches and sector-specific actions on mitigation Slide courtesy of Fernando Castellanos Silveira, UNFCCC

29. 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