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Section 2
Section 1
Section 2
Global Warming Levels (GWLs)
For many climate and risk variables, the geographical patterns of changes in climatic impact-drivers110 and climate impacts for a level of global 
warming111 are common to all scenarios considered and independent of timing when that level is reached. This motivates the use of GWLs as a 
dimension of integration. {WGI Box SPM.1.4, WGI TS.1.3.2; WGII Box SPM.1} (Figure 3.1, Figure 3.2)
Risks
Dynamic interactions between climate-related hazards, exposure and vulnerability of the affected human society, species, or ecosystems result 
in risks arising from climate change. AR6 assesses key risks across sectors and regions as well as providing an updated assessment of the 
Reasons for Concern (RFCs) – ﬁve globally aggregated categories of risk that evaluate risk accrual with increasing global surface temperature. 
Risks can also arise from climate change mitigation or adaptation responses when the response does not achieve its intended objective, or when 
it results in adverse effects for other societal objectives. {WGII SPM A, WGII Figure SPM.3, WGII Box TS.1, WGII Figure TS.4; SR1.5 Figure SPM.2; 
SROCC Errata Figure SPM.3; SRCCL Figure SPM.2} (3.1.2, Cross-Section Box.2 Figure 1, Figure 3.3)
110 See Annex I: Glossary
111 See Annex I: Glossary. Here, global warming is the 20-year average global surface temperature relative to 1850–1900. The assessed time of when a certain global warming level 
is reached under a particular scenario is deﬁned here as the mid-point of the ﬁrst 20-year running average period during which the assessed average global surface temperature 
change exceeds the level of global warming. {WGI SPM footnote 26, Cross-Section Box TS.1}