Title page

Contents

1. Executive summary 4

2. Introduction 7

3. Methodology 11

3.1. Scenario definitions 11

3.2. Pathway development and temperature estimates 12

3.2.1. Constructing emissions pathways to 2100 12

3.2.2. Assessment of global warming levels and emissions gaps for each scenario 13

3.3. Net zero targets 13

3.4. 1.5℃ aligned 2030 targets 14

3.5. Uncertainties in our analysis 14

4. Results and discussion 15

4.1. Progress in narrowing the gap 16

4.2. Stronger ambition by all G20 members could keep 1.5℃ within reach 18

4.3. Closing the G20 ambition gap to 1.5℃ 19

4.4. What more needs to be done to keep 1.5℃ alive? 21

5. Conclusion: a growing urgency for G20 governments to act 23

6. Appendix 24

7. References 28

8. Endnotes 31

Table 1. Summary of G20 climate commitments (as of August 2021) 9

Figure 1. Mapping the current G20 climate commitments 8

Figure 2. The impact of different G20 ambition levels on limiting global temperature rise 15

Figure 3. Most of the 2030 emissions gap can be closed by enhanced G20 ambition 16

Figure 4. Emissions gaps in 2030 between G20 targets and 1.5℃ domestic pathways 20

Boxes

Box 1. Vulnerable countries lead the world on climate ambition 22

Table 1. 2030 and mid-century emissions assumptions under thec urrent commitments scenario 24

Table 2. 2030 and mid-century emissions assumptions under the announced commitments scenario 25

Table 3. Net zero assumptions under the enhanced ambition scenario 26

Table 4. LULUCF assumptions for estimating the impact of net zero targets on emissions 26

Table 5. Ambition gap between G20 current targets and 1.5 ℃ compatible emissions level for 2030 27