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Section 3
Section 1
Section 3
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Gigatons of CO2 equivalent per year (GtCO2-eq/yr) 
CO2
GHG
CO2
GHG
CH4
CO2
GHG
CH4
a) While keeping warming to 1.5°C    
(>50%) with no or limited overshoot
b) While keeping warming to  2°C    (>67%)
c) Timing for net zero 
net zero
net zero
Historical
Historical
Policies in place in 2020
Policies in place in 2020
GHGs reach net zero 
later than CO2
not all 
scenarios 
reach net 
zero GHG 
by 2100
Global modelled pathways that limit warming to 1.5°C (>50%) with 
no or limited overshoot reach  net zero  CO2 emissions around 2050
Total  greenhouse gases (GHG)  reach net zero later
Figure 3.6: Total GHG, CO2 and CH4 emissions and timing of reaching net zero in different mitigation pathways. Top row: GHG, CO2 and CH4 emissions over time (in 
GtCO2eq) with historical emissions, projected emissions in line with policies implemented until the end of 2020 (grey), and pathways consistent with temperature goals in colour 
(blue, purple, and brown, respectively). Panel (a) (left) shows pathways that limit warming to 1.5°C (>50%) with no or limited overshoot (C1) and Panel (b) (right) shows 
pathways that limit warming to 2°C (>67%) (C3).