Avoiding dangerous climate change

See also: Climate change mitigation

The related terms "avoiding dangerous climate change" and "preventing dangerous anthropogenic interference with the climate system" date to 1995 and earlier, in the Second Assesment Report (SAR)^[1] of the International Panel on Climate Change (IPCC) and previous science it cites.

In 2002, the United Nations Framework Convention on Climate Change (UNFCCC),^[2] an international organization estabished by treaty in 1992, adopted a formal Framework Convention policy.^[3] Its Article 2, "Objective," is:

"The ultimate objective of this Convention and any related legal instruments that the Conference of the Parties may adopt is to achieve, in accordance with the relevant provisions of the Convention, stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. Such a level should be achieved within a time-frame sufficient to allow ecosystems to adapt naturally to climate change, to ensure that food production is not threatened and to enable economic development to proceed in a sustainable manner." (note: bolding added) ^[3]

Avoiding dangerous climate change and similar, equivalent terms have continued in common usage in the policy community,^[4][5] scientific literature,^[6][7] and news media.^[8][9][10] The problem that arises is to decide what level of interference would lead to "dangerous" change.

Avoiding dangerous climate change in the current scientific context

Limiting the average global surface temperature increase of 2°C over the pre-industrial average has, since the 1990s, been commonly regarded as an adequate means of avoiding dangerous climate change, in science and policy making.^[11][12] However, recent science has shown that the weather, environmental and social impacts of 2°C rise are much greater than the earlier science indicated, and that impacts for a 1°C rise are now expected to be as great as those previously assumed for a 2°C rise.^[13] (The diagrams also show the effects expected for a temperature rise of as much as 5°C.) In a July 2011 speech, climate scientist Kevin Anderson explained that for this reason, avoiding dangerous climate in the conventional sense is no longer possible, because the temperature rise is already close to 1°C, with effects formerly assumed for 2°C.^[14][15] Moreover, Anderson's presentation demonstrates reasons why a temperature rise of 4°C by 2060 is a likely outcome, given the record to date of action on climate, economic realities, and short window of time remaining for limiting the average surface temperature rise to 2°C or even 3°C.^[14] He also states that a 4°C rise would likely be an unstable state, leading to further increases in following decades regardless of mitigation measures that may be taken.^[14]

The consequences of failing to avoid dangerous climate change have been explored in two recent scientific conferences: the 4 degrees and beyond climate change conference held Oxford university it 2009; and the Four Degrees Or More? Australia in a Hot World held at the Univ. of Melbourne in July 2011.

A 2005 scientific symposium on avoiding dangerous climate change

"Avoiding Dangerous Climate Change: A Scientific Symposium on Stabilisation of Greenhouse Gases" was a 2005 international conference that examined the link between atmospheric greenhouse gas concentration, and the 2 °C (3.6 °F) ceiling on global warming thought necessary to avoid the most serious effects of global warming. Previously this had generally been accepted as being 550 ppm.

The conference took place under the United Kingdom's presidency of the G8, with the participation of around 200 'internationally renowned' scientists from 30 countries. It was chaired by Dennis Tirpak and hosted by the Hadley Centre for Climate Prediction and Research in Exeter, from 1 February to 3 February.^[16]

Objectives of the symposium:

Global carbon dioxide emissions through year 2004

Global average surface temperature 1880 to 2009, with a zero variance point set at the average temperature between 1961 and 1990.

The conference was called to bring together the latest research into what would be necessary to achieve the objective of the 1992 United Nations Framework Convention on Climate Change:

to achieve, in accordance with the relevant provisions of the Convention, stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system.

It was also intended to encourage further research in the area. An initial assessment of the subject had been included in the 2001 IPCC Third Assessment Report; however, the topic had received relatively little international discussion.^[17]

Specifically, the conference explored three issues:

• For different levels of climate change what are the key impacts, for different regions and sectors and for the world as a whole?
• What would such levels of climate change imply in terms of greenhouse gas stabilisation concentrations and emission pathways required to achieve such levels?
• What options are there for achieving stabilisation of greenhouse gases at different stabilisation concentrations in the atmosphere, taking into account costs and uncertainties?

The symposium's conclusions:

Among the conclusions reached, the most significant was a new assessment of the link between the concentration of greenhouse gases in the atmosphere and the increase in global temperature levels. Some researchers have argued that the most serious consequences of global warming might be avoided if global average temperatures rose by no more than 2 °C (3.6 °F) above pre-industrial levels (1.4 °C above present levels). It had generally been assumed that this would occur if greenhouse gas concentrations rose above 550 ppm carbon dioxide equivalent by volume. This concentration was, for example, informing government in certain countries, including the European Union.^[18]

The conference concluded that, at the level of 550 ppm, it was likely that 2 °C would be exceeded, according to the projections of more recent climate models. Stabilising greenhouse gas concentrations at 450 ppm would only result in a 50% likelihood of limiting global warming to 2 °C, and that it would be necessary to achieve stabilisation below 400 ppm to give a relatively high certainty of not exceeding 2 °C.^[19]

The conference also claimed that, if action to reduce emissions is delayed by 20 years, rates of emission reduction may need to be 3 to 7 times greater to meet the same temperature target.^[19]

Reactions to the symposium:

As a result of changing opinion on the 'safe' atmospheric concentration of greenhouse gases, to which this conference contributed, the UK Government changed the target in the Climate Change Act from 60% to 80% by 2050.^[20]

See also

Energy portal

• 4 Degrees and Beyond International Climate Conference
• Action on climate change
• Climate change mitigation scenarios
• Environmental impact of aviation
• Hypermobility (travel)
• Index of climate change articles

References

1. ^ IPCC 1995. Second Assessment Report: Climate change 1995.
2. ^ The Kyoto Protocol is a protocol to the UNFCCC.
3. ^ ^{a b} UNFCC 2002. Framework Convention
4. ^ IPCC 2001. Third Assessment Report: Climate change 2001.
5. ^ IPCC 2007. Fourth Assessment Report: Climate change 2007.
6. ^ Schneider, S. (2009). The worst-case scenario. Nature (458:7242, p.1104-1105).
7. ^ Lenton, T. (2011). 2 °C or not 2 °C? That is the climate question. Nature (473:7).
8. ^ UPI. 27 Oct. 2011. Review: Warming target needs action now
9. ^ Reuters. 23 May 2011. Climate change warnings add heat to Australia CO2 price.
10. ^ The Australian. 1 June 2011. Clash of cultures, economics and ideology
11. ^ den Elzen M.; Meinshausen M. (2005). Netherlands Env. Assessment Agengy. Meeting the EU 2°C climate target: global and regional emission implications.
12. ^ Rogelj, J.; Hare, B,; Nabel, J.; Macey, K.; Schaeffer, M.; Markmann, K.; Meinshausen, M. (2009). Halfway to Copenhagen, no way to 2°C. Nature Reports Climate Change.
13. ^ Smith, JB.; Schneider, SH.; Oppenheimer, M.;, Yohe, GW.; Hare, W.; Mastrandrea, MD.; Patwardhan, A.; Burton, I.; Corfee-Morlot, J.; Magadza, CH.; others (2009). Assessing dangerous climate change through an update of the Intergovernmental Panel on Climate Change (IPCC)“reasons for concern”. Proceedings of the National Academy of Sciences (106:11; p.4133).
14. ^ ^{a b c} Anderson, K. (2011). Multi-media presentation. Climate Change: Going beyond dangerous -- Brutal numbers, tenuous hope, or cognitive dissonance? July 2011.
15. ^ Anderson, K.; Bows, A. (2011). Beyond 'dangerous' climate change: emission scenarios for a new world. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences (369:1934, p.20-44).
16. ^ "Climate Stabilisation Conference - Exeter 2005". Government News Network. 4 November 2004. http://www.gnn.gov.uk/content/detail.asp?NewsAreaID=2&ReleaseID=134475. Retrieved 15 March 2007. 
17. ^ "Avoiding Dangerous Climate Change - Background". Met Office. 2005. http://www.stabilisation2005.com/background.html. Retrieved 16 March 2007. 
18. ^ "Community Strategy on Climate Change - Council Conclusions". Council of the European Union. 22 June 1996?. http://ue.eu.int/ueDocs/cms_Data/docs/pressData/en/envir/011a0006.htm. Retrieved 15 March 2007. 
19. ^ ^{a b} "International Symposium on the Stabilisation of greenhouse gas concentrations - Report of the International Scientific Steering Committee". Met Office. 10 May 2005. http://www.stabilisation2005.com/outcomes.html. Retrieved 15 March 2007. 
20. ^ "UK leads world with commitment to cut emissions by 80% by 2050". Department of Energy and Climate Change. 16 October 2008. http://nds.coi.gov.uk/environment/fullDetail.asp?ReleaseID=381477&NewsAreaID=2&NavigatedFromDepartment=False. Retrieved 28 October 2008. ^{[dead link]}

Further reading

• Avoiding Dangerous Climate Change, Editors: Hans Joachim Schellnhuber, Wolfgang Cramer, Nebojsa Nakicenovic, Tom Wigley, and Gary Yohe, Cambridge University Press, February 2006, ISBN 9780521864718 DOI: 10.2277/0521864712.
  • PDF version

External links

• Avoiding Dangerous Climate Change - official conference website
• Tyndall Centre - A strategic assessment of scientific and behavioural perspectives on 'dangerous' climate change
• RSPB - Keeping below 2 degrees: Avoiding dangerous climate change
• WWF-UK - 2°C Is Too Much! Evidence and Implications of Dangerous Climate Change in the Arctic
• Netherlands Environmental Assessment Agency - Meeting the European Union 2°C climate target: global and regional emission implications
• Dr. James Hansen, Climate Scientist's web page

News

• April 19, 2007, Reuters: World needs to axe greenhouse gases by 80% by 2050
• February 1, 2006, Euractive: UK chief scientific adviser: Keeping CO2 concentration below 450ppm is 'unfeasible'
• January 30, 2006, BBC: Stark warning over climate change
• January 30, 2006, BBC: Climate report: the main points
• January 29, 2006, Washington Post: Debate on Climate Shifts to Issue of Irreparable Change
• January 1, 2006, Times online: World has only 20 years to stop climate disaster
• February 4, 2005, Environment News Service: Catastrophic Climate Change Risk Accelerating, Scientists Warn
• February 3, 2005, Guardian Unlimited: Climate conference hears degree of danger