To combat climate change effectively, stringent climate policies are essential. Over the past decades, various policy measures have been proposed and implemented, yet national climate policies often fall short in delivering the necessary stringency to effectively reduce emissions. This is due to a complex interplay of political, economic, and social factors. Key determinants shaping policy ambition include institutional, politico-economic, and socio-economic factors. Recent research has examined these determinants, shedding light on what drives policy stringency, public support, and the effectiveness of different climate policy measures.
Predictors of Climate Policy Stringency
Von Dulong & Hagen (2025) apply conditional random forests to analyze the key drivers of climate policy stringency, overcoming some limitations of traditional econometric methods by accounting for strong correlations between predictors. This approach enables them to rank the importance of 22 politico-economic, institutional, and socio-economic factors across 95 countries. The findings reveal that the most influential predictors of stringent climate policies, in decreasing order, are freedom (of the press, media, associations, and elections), governmental effectiveness, control of corruption, GDP, and education. Notably, the relationship between many predictors and policy stringency is highly non-linear. For instance, once freedom or GDP surpasses a certain threshold, climate policies become significantly more stringent. However, below these thresholds, variations in these predictors have little impact on policy stringency. These insights highlight the importance of institutional quality and economic conditions in shaping ambitious climate policies.
Determinants of Public Support for Climate Policies
Dechezleprêtre et al. (2025) analyze global public perceptions of climate change and policy support, drawing on survey data from 40,000 respondents across 20 countries. They find that support for climate policies is primarily shaped by three key factors: their perceived effectiveness in reducing emissions, their impact on lower-income households, and their economic implications for individuals. Policies seen as both effective and fair—such as investments in clean energy and progressive carbon pricing—tend to receive greater public support. Socioeconomic factors influence policy preferences, with higher education levels and left-leaning political views associated with stronger support, while reliance on cars and limited access to public transportation tend to reduce it.
Effectiveness of Climate Policy Measures
Stechemesser et al. (2024) analyze the effectiveness of various climate policy measures in a global, systematic ex post evaluation across economic sectors. Their study evaluates 1,500 policies implemented between 1998 and 2022 across 41 countries, using a machine learning–enhanced difference-in-differences approach. They identify 63 successful interventions that collectively reduced emissions by 0.6 to 1.8 billion metric tonnes of CO₂. The findings highlight the effectiveness of specific, yet understudied, policy combinations, emphasizing the crucial role of price-based instruments within well-structured policy mixes.
The Spread of Carbon Pricing Policies
Linsenmeier et al. (2023) show that carbon pricing policies spread across countries through policy diffusion, with adoption in one nation increasing the likelihood of implementation in neighboring countries. Monte Carlo simulations suggest that emissions reductions from this diffusion effect can often exceed the direct domestic reductions achieved by individual nations. These findings underscore the importance of ambitious climate policies, even in countries with low domestic emissions, as they can drive broader global climate action.