Editing Global warming potential (section)

=== Use in Kyoto Protocol and for reporting to UNFCCC ===
Under the [[Kyoto Protocol]], in 1997 the Conference of the Parties standardized international reporting, by deciding (see decision number 2/CP.3) that the values of GWP calculated for the [[IPCC Second Assessment Report]] were to be used for converting the various greenhouse gas emissions into comparable {{CO2}} equivalents.<ref>
{{cite book |author=Conference of the Parties |url=http://unfccc.int/resource/docs/cop3/07a01.pdf |title=Report of the Conference of the Parties on its third session, held at Kyoto from 1 to 11 December 1997 Addendum Part Two: Action taken by the Conference of the Parties at its third session |date=25 March 1998 |publisher=[[UNFCCC]] |contribution=Methodological issues related to the Kyoto Protocol |access-date=17 January 2011 |archive-url=https://web.archive.org/web/20000823193833/http://www.unfccc.int/resource/docs/cop3/07a01.pdf |archive-date=2000-08-23 |url-status=live}}</ref><ref>{{cite journal |last1=Godal |first1=Odd |last2=Fuglestvedt |first2=Jan |date=2002 |title=Testing 100-year global warming potentials: Impacts on compliance costs and abatement profile |journal=Climatic Change |volume=52 |issue=1/2 |pages=93–127 |doi=10.1023/A:1013086803762 |s2cid=150488348 |id={{ProQuest|198550594}}}}</ref>

After some intermediate updates, in 2013 this standard was updated by the Warsaw meeting of the [[United Nations Framework Convention on Climate Change|UN Framework Convention on Climate Change]] (UNFCCC, decision number 24/CP.19) to require using a new set of 100-year GWP values. They published these values in Annex III, and they took them from the [[IPCC Fourth Assessment Report]], which had been published in 2007.<ref name="unfccc19" /> Those 2007 estimates are still used for international comparisons through 2020,<ref name="epa20" /> although the latest research on warming effects has found other values, as shown in the tables above.

Though recent reports reflect more scientific accuracy, countries and companies continue to use the [[IPCC Second Assessment Report]] (SAR)<ref name="sar" /> and IPCC Fourth Assessment Report values for reasons of comparison in their emission reports. The [[IPCC Fifth Assessment Report]] has skipped the 500-year values but introduced GWP estimations including the climate-carbon feedback (f) with a large amount of uncertainty.<ref name="ar5" />