Imma Perfetto
Cosmos science journalist
Analysis of 1,500 global climate policies has revealed new insights into the policy combinations that are effective in reducing emissions.
The new research finds only 63 policy interventions successfully reduced total emissions between 0.6 billion and 1.8 billion tons of CO2.
Effective national climate policies are crucial to achieve the Paris Agreement’s goal to limit average global warming to well below 2 °C above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5 °C.
However, modelling suggests current efforts fall short of the required emission reductions.
“Our results provide a clear yet sobering perspective on the policy effort necessary for closing the remaining emissions gap of 23 billion tons carbon dioxide (CO2) by 2023,” the authors write in the paper, which is published in Science.
To determine the climate policy measures that result in meaningful emission reductions, researchers evaluated 1,500 policy interventions implemented across 41 countries between 1998 and 2022.
“Our findings demonstrate that more policies do not necessarily equate to better outcomes,” says lead author Dr Nicolas Koch from the Potsdam Institute for Climate Impact Research (PIK) and the Mercator Research Institute on Global Commons and Climate Change (MCC), Germany.
“Instead, the right mix of measures is crucial. For example, subsidies or regulations alone are insufficient; only in combination with price-based instruments, such as carbon and energy taxes, can they deliver substantial emission reductions.”
The findings also highlight how successful policy mixes vary across sectors. For example, pricing mechanisms are particularly effective in industry and electricity sectors, whereas building and transport sectors benefit from a combination of incentives and regulations.
“While it remains challenging to precisely disentangle the effects of individual measures within a policy mix, our 63 success cases provide systematic insights into effective policy combinations and show how well-designed policy mixes depend on sectors and the development level of countries,” says lead author Dr Annika Stechemesser of PIK.
In contrast to developed economies, they found no successful pricing interventions with large emission reductions in the electricity sector of developing economies.
“This knowledge is vital for supporting policymakers and society in the transition to climate neutrality,” says Stechemesser.
The researchers used data from the climate policy database from the Organization for Economic Cooperation and Development (OECD) and machine learning to arrive at the results.
An overview of the results, analysis and methods is presented in an interactive website, Climate Policy Explorer.
