{WGI SPM C.2, WGI SPM C.2.1, 
WGI SPM C.2.3; WGII SPM B.6, WGII SPM B.6.1, WGII SPM B.6.2; SR1.5 3.6}
The larger the overshoot, the more net negative CO2 emissions needed 
to return to a given warming level (high conﬁdence). Reducing global 
temperature by removing CO2 would require net negative emissions of 
220 GtCO2 (best estimate, with a likely range of 160 to 370 GtCO2) 
for every tenth of a degree (medium conﬁdence). Modelled pathways 
that limit warming to 1.5°C (>50%) with no or limited overshoot reach 
median values of cumulative net negative emissions of 220 GtCO2 
by 2100, pathways that return warming to 1.5°C (>50%) after high 
overshoot reach median values of 360 GtCO2 (high conﬁdence).137 
More rapid reduction in CO2 and non-CO2 emissions, particularly 
methane, limits peak warming levels and reduces the requirement 
for net negative CO2 emissions and CDR, thereby reducing feasibility 
and sustainability concerns, and social and environmental risks (high 
confidence). {WGI SPM D.1.1; WGIII SPM B.6.4, WGIII SPM C.2, 
WGIII SPM C.2.2, WGIII Table SPM.2}