Editing IPCC Second Assessment Report (section)

==Conclusions==
Working Group I, dealing with the scientific aspects of climate, stated that
{{quote|  carbon dioxide remains the most important contributor to anthropogenic forcing of climate change; projections of future global mean temperature change and sea level rise confirm the potential for human activities to alter the Earth's climate to an extent unprecedented in human history; and the long time-scales governing both the accumulation of greenhouse gases in the atmosphere and the response of the climate system to those accumulations, means that many important aspects of climate change are effectively irreversible.<ref>{{Harvnb|IPCC SAR SYR|1995}}, Preface, [http://www.ipcc.ch/ipccreports/sar/wg_I/ipcc_sar_wg_I_full_report.pdf p. xi] {{Webarchive|url=https://web.archive.org/web/20111015170030/http://ipcc.ch/ipccreports/sar/wg_I/ipcc_sar_wg_I_full_report.pdf |date=2011-10-15 }}.</ref>
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Working Group I subsequently characterized its reports in the First and Second Assessments as progressing from an understanding that the [[greenhouse effect]] is well understood, greenhouse gases are increasing (due largely to human activity), and therefore should lead to significant [[global warming]] (though lack of understanding limited specific regional predictions), to a greater understanding (despite continuing uncertainties) that global warming continues and is most likely due to human activity, and that very substantial cuts in emissions would be required to stabilize greenhouse gas concentrations.<ref>{{Harvnb|IPCC TAR WG1|2001}}, Technical Summary, Section A.2, [http://www.ipcc.ch/ipccreports/sar/wg_I/ipcc_sar_wg_I_full_report.pdf pp. 22–3] {{Webarchive|url=https://web.archive.org/web/20111015170030/http://ipcc.ch/ipccreports/sar/wg_I/ipcc_sar_wg_I_full_report.pdf |date=2011-10-15 }}</ref>

<!-- From earliar version.  Undecided whether to track them down and retain them.
# Greenhouse gas concentrations have continued to increase
# Anthropogenic aerosols tend to produce negative radiative forcings
# Climate has changed over the past century
# The balance of evidence suggests a discernible human influence on global climate
# Climate is expected to continue to change in the future
# There are still many uncertainties

Its eighth chapter noted "these results indicate that the observed trend in global mean temperature over the past 100 years is unlikely to be entirely natural in origin. More importantly, there is evidence of an emerging pattern of climate response to forcings by greenhouse gases and sulphate aerosols in the observed climate record. Taken together, these results point towards a human influence on global climate." [ch 8, summary, p 412].
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Working Group II assessed whether the range of plausible impacts of global warming constitutes dangerous anthropogenic interference with the climate system,<ref>{{Harvnb|IPCC SAR SYR|1995}}, [http://www.ipcc.ch/pdf/climate-changes-1995/ipcc-2nd-assessment/2nd-assessment-en.pdf p. 27] {{Webarchive|url=https://web.archive.org/web/20180913173945/http://www.ipcc.ch/pdf/climate-changes-1995/ipcc-2nd-assessment/2nd-assessment-en.pdf |date=2018-09-13 }}.</ref> while Working Group III provided information to help countries "take decisions they believe are most appropriate for their specific circumstances".<ref>{{Harvnb|IPCC SAR SYR|1995}}, [http://www.ipcc.ch/pdf/climate-changes-1995/ipcc-2nd-assessment/2nd-assessment-en.pdf p. 45] {{Webarchive|url=https://web.archive.org/web/20180913173945/http://www.ipcc.ch/pdf/climate-changes-1995/ipcc-2nd-assessment/2nd-assessment-en.pdf |date=2018-09-13 }}.</ref>