In 2005, an international conference titled Avoiding Dangerous Climate Change: A Scientific Symposium on Stabilisation of Greenhouse Gases examined the link between atmospheric
greenhouse gas
A greenhouse gas (GHG or GhG) is a gas that absorbs and emits radiant energy within the thermal infrared range, causing the greenhouse effect. The primary greenhouse gases in Earth's atmosphere are water vapor (), carbon dioxide (), met ...
concentration and
global warming
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate variability and change, Climate change in a broader sense also includes ...
and
its effects. The conference name was derived from Article 2 of the charter for the
United Nations Framework Convention on Climate Change
The United Nations Framework Convention on Climate Change (UNFCCC) established an international environmental treaty to combat "dangerous human interference with the climate system", in part by stabilizing greenhouse gas concentrations in th ...
The conference explored the possible impacts at different levels of
greenhouse gas emissions
Greenhouse gas emissions from human activities strengthen the greenhouse effect, contributing to climate change. Most is carbon dioxide from burning fossil fuels: coal, oil, and natural gas. The largest emitters include coal in China and ...
and how the
climate might be stabilized at a desired level. The conference took place under the
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the European mainland, continental mainland. It comprises England, Scotlan ...
's presidency of the
G8, with the participation of around 200 "internationally renowned" scientists from 30 countries. It was chaired by
Dennis Tirpak
Dennis Tirpak is a climate change scientist.
Tirpak was the director of the Global Climate Change Policy Division at the United States Environmental Protection Agency from 1984–1992. He was the coordinator of science and technology at the Unite ...
and hosted by the
Hadley Centre for Climate Prediction and Research in
Exeter
Exeter () is a city in Devon, South West England. It is situated on the River Exe, approximately northeast of Plymouth and southwest of Bristol.
In Roman Britain, Exeter was established as the base of Legio II Augusta under the personal c ...
, from 1 February to 3 February.
The conference was one of many meetings leading up to the 2015
Paris Agreement, at which the international community agreed to limit global warming to no more than 2ºC in order to have a 50-50 chance of avoiding dangerous climate change. However, a 2018 published study points at a threshold at which temperatures could rise to 4 or 5 degrees through
self-reinforcing feedbacks in the climate system, suggesting the threshold (or 'tipping point') is below the 2 degree temperature target.
Objectives

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
The United Nations Framework Convention on Climate Change (UNFCCC) established an international environmental treaty to combat "dangerous human interference with the climate system", in part by stabilizing greenhouse gas concentrations in th ...
:
:to achieve, in accordance with the relevant provisions of the Convention, stabilization of
greenhouse gas
A greenhouse gas (GHG or GhG) is a gas that absorbs and emits radiant energy within the thermal infrared range, causing the greenhouse effect. The primary greenhouse gases in Earth's atmosphere are water vapor (), carbon dioxide (), met ...
concentrations in the atmosphere at a level that would prevent dangerous
anthropogenic
Anthropogenic ("human" + "generating") is an adjective that may refer to:
* Anthropogeny, the study of the origins of humanity
Counterintuitively, anthropogenic may also refer to things that have been generated by humans, as follows:
* Human i ...
interference with the climate system.
It was also intended to encourage further research in the area. In the 2001
IPCC Third Assessment Report
The IPCC Third Assessment Report (TAR), ''Climate Change 2001'', is an assessment of available scientific and socio-economic information on climate change by the IPCC. Statements of the IPCC or information from the TAR are often used as a referen ...
, an initial assessment of the subject had been included; however, the topic had received relatively little international discussion.
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
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to ...
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?
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
Pre-industrial society refers to social attributes and forums of political and cultural organization that were prevalent before the advent of the Industrial Revolution, which occurred from 1750 to 1850. ''Pre-industrial'' refers to a time before ...
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
Global warming potential (GWP) is the heat absorbed by any greenhouse gas in the atmosphere, as a multiple of the heat that would be absorbed by the same mass of carbon dioxide (). GWP is 1 for . For other gases it depends on the gas and the time ...
by volume. This concentration was, for example, informing government in certain countries, including the
European Union
The European Union (EU) is a supranational political and economic union of member states that are located primarily in Europe. The union has a total area of and an estimated total population of about 447million. The EU has often been ...
.
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 model
Numerical climate models use quantitative methods to simulate the interactions of the important drivers of climate, including atmosphere, oceans, land surface and ice. They are used for a variety of purposes from study of the dynamics of the ...
s. Stabilising
greenhouse gas
A greenhouse gas (GHG or GhG) is a gas that absorbs and emits radiant energy within the thermal infrared range, causing the greenhouse effect. The primary greenhouse gases in Earth's atmosphere are water vapor (), carbon dioxide (), met ...
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.
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.
[
]
Reaction
As a result of changing opinion on the 'safe' atmospheric concentration of greenhouse gases, to which this conference contributed, the UK government
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changed the target in the Climate Change Act from 60% to 80% by 2050.
See also
*4 Degrees and Beyond International Climate Conference
The 4 Degrees and Beyond International Climate Conference, subtitled ''Implications of a Global Climate Change of 4+ Degrees for People, Ecosystems and the Earth-system'', was held 28–30 September 2009 at Oxford, United Kingdom. The three-day c ...
*Action on climate change
Climate change mitigation is action to limit climate change by reducing emissions of greenhouse gases or removing those gases from the atmosphere. The recent rise in global average temperature is mostly caused by emissions from fossil fuels bur ...
* Climate change mitigation scenarios
*Environmental impact of aviation
Like other emissions resulting from fossil fuel combustion, aircraft engines produce gases, noise, and particulates, raising environmental concerns over their global effects and their effects on local air quality.
Jet airliners contribute ...
* Hypermobility (travel)
* Index of climate change articles
References
Further reading
*Related book: ''Avoiding Dangerous Climate Change'', Editors: Hans Joachim Schellnhuber, Wolfgang Cramer, Nebojsa Nakicenovic, Tom Wigley, and Gary Yohe, Cambridge University Press, February 2006, .
**
External links
*
* Tyndall Centre
A strategic assessment of scientific and behavioural perspectives on 'dangerous' climate change
* WWF-UK
2°C Is Too Much! Evidence and Implications of Dangerous Climate Change in the Arctic
*Netherlands Environmental Assessment Agency
*
;News
*April 19, 2007, ''Reuters''
World needs to axe greenhouse gases by 80 pct: report
*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''
*January 1, 2006, ''Times online''
World has only 20 years to stop climate disaster
*February 3, 2005, ''Guardian Unlimited''
Climate conference hears degree of danger
{{Global warming
Climate change conferences
2005 in the environment