Climate policies that achieved major emission reductions: Global evidence from two decades
Science, 2024
Abstract: Meeting the Paris Agreement’s climate targets necessitates better knowledge about which climate policies work in reducing emissions at the necessary scale. We provide a global, systematic ex post evaluation to identify policy combinations that have led to large emission reductions out of 1500 climate policies implemented between 1998 and 2022 across 41 countries from six continents. Our approach integrates a comprehensive climate policy database with a machine learning–based extension of the common difference-in-differences approach. We identified 63 successful policy interventions with total emission reductions between 0.6 billion and 1.8 billion metric tonnes CO2. Our insights on effective but rarely studied policy combinations highlight the important role of price-based instruments in well-designed policy mixes and the policy efforts necessary for closing the emissions gap.
As part of an international research team, we have published the first global assessment of climate policies in the four most critical emission sectors in the journal Science.
We unveiled the first comprehensive global evaluation of 1,500 climate policy measures from 41 countries across six continents. We identified ‘emission breaks’ and assigned them policy interventions, pinpointing where policies may have had a large impact. The break detection methodology, called indicator saturation estimation, developed at Climate Econometrics, allows break indicators for all possible dates to be examined objectively using a variant of machine learning. This unprecedented study provides a detailed impact analysis of the wide range of climate policy measures implemented across the planet over the last two decades.
We have identified 63 cases of successful climate policies with large emission reductions with the key characteristic of these successful cases being the inclusion of tax and price incentives in well-designed policy mixes. Our study also shows that if more countries relied on policies like these ones, the remaining emissions gap for 2030 could be closed by as much as 26% to 41%. The identified successful policies have led to an average emission reduction of 19 percent. In total, the 63 policy interventions reduced emissions between 0.6 and 1.8 billion tonnes of CO2.
For more detail on the identified policies, check out our Climate Policy Exporer where you can dive deeper into our results and findings.
[Data and code][Interactive web dashboard]
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