Query: Study finds low probability of both very low and very high climate sensitivities, and its lower estimate (as compared to the IPCC) is based on a new temperature reconstruction of the Last Glacial Maximum that may or may not withstand the test of time.

Relevant passages:
Kyoto Protocol <=SEP=> The Kyoto Protocol is an international treaty which extends the 1992 United Nations Framework Convention on Climate Change ( UNFCCC ) that commits State Parties to reduce greenhouse gas emissions , based on the fact that ( a ) global warming exists and ( b ) human-made CO2 emissions have caused it . The Kyoto Protocol was adopted in Kyoto , Japan , on 11 December 1997 and entered into force on 16 February 2005 . There are currently 192 parties ( Canada withdrew effective December 2012 ) to the Protocol .   The Kyoto Protocol implemented the objective of the UNFCCC to fight global warming by reducing greenhouse gas concentrations in the atmosphere to `` a level that would prevent dangerous anthropogenic interference with the climate system '' ( Art. 2 ) . The Protocol is based on the principle of common but differentiated responsibilities : it puts the obligation to reduce current emissions on developed countries on the basis that they are historically responsible for the current levels of greenhouse gases in the atmosphere .   The Protocol 's first commitment period started in 2008 and ended in 2012 . A second commitment period was agreed on in 2012 , known as the Doha Amendment to the protocol , in which 37 countries have binding targets : Australia , the European Union ( and its 28 member states ) , Belarus , Iceland , Kazakhstan , Liechtenstein , Norway , Switzerland , and Ukraine . Belarus , Kazakhstan and Ukraine have stated that they may withdraw from the Protocol or not put into legal force the Amendment with second round targets . Japan , New Zealand and Russia have participated in Kyoto 's first-round but have not taken on new targets in the second commitment period . Other developed countries without second-round targets are Canada ( which withdrew from the Kyoto Protocol in 2012 ) and the United States ( which has not ratified the Protocol ) . As of July 2016 , 66 states have accepted the Doha Amendment , while entry into force requires the acceptances of 144 states . Of the 37 countries with binding commitments , 7 have ratified .   Negotiations were held in the framework of the yearly UNFCCC Climate Change Conferences on measures to be taken after the second commitment period ends in 2020 . This resulted in the 2015 adoption of the Paris Agreement , which is a separate instrument under the UNFCCC rather than an amendment of the Kyoto protocol .

IPCC Fifth Assessment Report <=SEP=> The Fifth Assessment Report ( AR5 ) of the United Nations Intergovernmental Panel on Climate Change ( IPCC ) is the fifth in a series of such reports . The IPCC was established in 1988 by the World Meteorological Organization ( WMO ) and the United Nations Environment Programme ( UNEP ) to assess scientific , technical and socio-economic information concerning climate change , its potential effects and options for adaptation and mitigation .   The Fifth Assessment Report was finalized in 2014 . As had been the case in the past , the outline of the AR5 was developed through a scoping process which involved climate change experts from all relevant disciplines and users of IPCC reports ; in particular representatives from governments . Governments and organizations involved in the Fourth Report were asked to submit comments and observations in writing with the submissions analysed by the panel . The report was delivered in stages , starting with Working Group I 's report on the physical science basis , based on 9,200 peer-reviewed studies . The summaries for policy makers were released on 27 September 2013 for the first report , on 31 March 2014 for the second report entitled `` Impacts , Adaptation , and Vulnerability '' , and on 14 April 2014 for the third report entitled `` Mitigation of Climate Change '' . The Synthesis Report was released on 2 November 2014 , in time to pave the way for negotiations on reducing carbon emissions at the UN Climate Change Conference in Paris during late 2015 .

IPCC Third Assessment Report <=SEP=> The IPCC Third Assessment Report , Climate Change 2001 , is an assessment of available scientific and socio-economic information on climate change by the IPCC . The IPCC was established in 1988 by the United Nations Environment Programme ( UNEP ) and the UN 's World Meteorological Organization ( WMO ) '' ... to assess scientific , technical and socio-economic information relevant for the understanding of climate change , its potential impacts and options for adaptation and mitigation . '' -LSB- IPCC website -RSB- The Third Assessment Report ( TAR ) is the third of a series of assessments ; it has been superseded by the IPCC Fourth Assessment Report ( AR4 ) , released in 2007 .   Statements of the IPCC or information from the TAR are often used as a reference showing a scientific consensus on the subject of global warming , although a small minority of scientists take issue with the UN assessments ( see also Global warming controversy and Politics of global warming ) .

Climate sensitivity <=SEP=> Climate sensitivity is the equilibrium temperature change in response to changes of the radiative forcing . Therefore , climate sensitivity depends on the initial climate state , but potentially can be accurately inferred from precise palaeoclimate data . Slow climate feedbacks , especially changes of ice sheet size and atmospheric CO2 , amplify the total Earth system sensitivity by an amount that depends on the time scale considered .   Although climate sensitivity is usually used in the context of radiative forcing by carbon dioxide ( CO2 ) , it is thought of as a general property of the climate system : the change in surface air temperature ( ΔTs ) following a unit change in radiative forcing ( RF ) , and thus is expressed in units of ° C / ( W/m2 ) . For this to be useful , the measure must be independent of the nature of the forcing ( e.g. from greenhouse gases or solar variation ) ; to first order this is indeed found to be so .   The climate sensitivity specifically due to is often expressed as the temperature change in ° C associated with a doubling of the concentration of carbon dioxide in Earth 's atmosphere .   For coupled atmosphere-ocean global climate models ( e.g. CMIP5 ) the climate sensitivity is an emergent property : it is not a model parameter , but rather a result of a combination of model physics and parameters . By contrast , simpler energy-balance models may have climate sensitivity as an explicit parameter .   The terms represented in the equation relate radiative forcing ( RF ) to linear changes in global surface temperature change ( ΔTs ) via the climate sensitivity λ .   It is also possible to estimate climate sensitivity from observations ; however , this is difficult due to uncertainties in the forcing and temperature histories .