Manuel Linsenmeier, Mr. Adil Mohommad, and Gregor Schwerhoff
In this paper, we study the international diffusion of carbon pricing policies. In the first part, we empirically examine to what extent the adoption of carbon pricing in a given country can explain the subsequent adoption of the same policy in other countries. In the second part, we quantify the global benefits of policy diffusion in terms of greenhouse gas emission reductions elsewhere. To do so, we combine a large international dataset on carbon pricing with several other datasets. For causal identification, we estimate semi-parametric Cox proportional hazard models. We find robust and statistically significant evidence for policy diffusion.
Mr. Tobias Adrian, Mr. Patrick Bolton, and Alissa M. Kleinnijenhuis
We measure the gains from phasing out coal as the social cost of carbon times the quantity of avoided emissions. By comparing the present value of the benefits from avoided emissions against the present value of costs of ending coal plus the costs of replacing it with renewable energy, our baseline estimate is that the world can realize a net gain of 77.89 trillion USD. This represents around 1.2% of current world GDP every year until 2100. The net benefits from ending coal are so large that renewed efforts, carbon pricing, and other financing policies we discuss, should be pursued.
Maria Borga, Achille Pegoue, Mr. Gregory M Legoff, Alberto Sanchez Rodelgo, Dmitrii Entaltsev, and Kenneth Egesa
This paper presents estimates of the carbon emissions of FDI from capital formation funded by FDI and the production of foreign-controlled firms. The carbon intensity of capital formation financed by FDI has trended down, driven by reductions in the carbon intensity of electricity generation. Carbon emissions from the operations of foreign-controlled firms are greater than those from their capital formation. High emission intensities were accompanied by high export intensities in mining, transport, and manufacturing. Home country policies to incentivize firms to meet strict emissions standards in both their domestic and foreign operations could be important to reducing emissions globally.
Manuel Linsenmeier, Mr. Adil Mohommad, and Gregor Schwerhoff
Carbon pricing is considered the most efficient policy to reduce greenhouse gas emissions but it has also been conjectured that other policies need to be implemented first to remove certain economic and political barriers to stringent climate policy. Here, we examine empirical evidence on the the sequence of policy adoption and climate policy portfolios of G20 economies and other major emitters that eventually implemented a national carbon price. We find that all countries adopted carbon pricing late in their instrument sequence after the adoption of (almost) all other instrument types. Furthermore, we find that countries that adopted carbon pricing in a given year had significantly larger climate policy portfolios than those that did not. In the last part of the paper, we examine heterogeneity among countries that eventually adopted a carbon price. We find large variation in the size of policy portfolios of adopters of carbon pricing, with more recent adopters appearing to have introduced carbon pricing with smaller portfolios. Furthermore, countries that adopted carbon pricing with larger policy portfolios tended to implement a higher carbon price. Overall, our results thus suggest that policy sequencing played an important role in climate policy, specifically the adoption of carbon pricing, over the last 20 years.
Fragile states in sub-Saharan Africa (SSA) face challenges to respond to the effects of climate shocks and rising temperatures. Fragility is linked to structural weaknesses, government failure, and lack of institutional basic functions. Against this setup, climate change could add to risks. A panel fixed effects model (1980 to 2019) found that the effect of a 1◦C rise in temperature decreases income per capita growth in fragile states in SSA by 1.8 percentage points. Panel quantile regression models that account for unobserved individual heterogeneity and distributional heterogeneity, corroborate that the effects of higher temperature on income per capita growth are negative while the impact of income per capita growth on carbon emissions growth is heterogeneous, indicating that higher income per capita growth could help reduce carbon emissions growth for high-emitter countries. These findings tend to support the hypothesis behind the Environmental Kuznets Curve and the energy consumption growth literature, which postulates that as income increases, emissions increase pari passu until a threshold level of income where emissions start to decline.
To reach the global net-zero goal, the level of carbon emissions has to fall substantially at speed rarely seen in history, highlighting the need to identify structural breaks in carbon emission patterns and understand forces that could bring about such breaks. In this paper, we identify and analyze structural breaks using machine learning methodologies. We find that downward trend shifts in carbon emissions since 1965 are rare, and most trend shifts are associated with non-climate structural factors (such as a change in the economic structure) rather than with climate policies. While we do not explicitly analyze the optimal mix between climate and non-climate policies, our findings highlight the importance of the nonclimate policies in reducing carbon emissions. On the methodology front, our paper contributes to the climate toolbox by identifying country-specific structural breaks in emissions for top 20 emitters based on a user-friendly machine-learning tool and interpreting the results using a decomposition of carbon emission ( Kaya Identity).
Mr. Philip Barrett, Katharina Bergant, Jean Chateau, and Rui Mano
The run up to the 26th Climate Change Conference has brought tackling climate change to the fore of global policy making. In this context, the U.S. administration has recently unveiled new climate targets. This paper elaborates on the administration’s plans and uses two models developed at the IMF to illustrate key macro-climate trade-offs. First, a model with endogenous fuel-specific technological change shows that subsidies cannot substitute for explicit carbon pricing and that even a moderate carbon tax can greatly economize on the overall fiscal cost of the package. Second, a rich sectoral model shows that there are only very marginal economic costs from front-loading the decarbonization of the power sector but there are large accompanying environmental benefits. Regulations can be effective in the power sector because they provide an appropriate shadow cost to carbon. However, a carbon tax would still be more efficient and easier to administer. Finally, as the economy transitions away from fossil-fueled power generation, there would be a significant reallocation of labor across sectors and locations that would need to be handled carefully to limit the social costs of the transition.
Climate financing and compensation have emerged as key themes in the international climate mitigation debate. According to one argument in support of compensation, advanced economies (AEs) have used up much of the atmosphere’s absorptive capacity, thus causing global warming and blocking a similar, fossil-fuel driven development path for emerging markets and developing economies (EMDEs). This paper develops a simple model of a sequential, fossil-fuel driven development process to discuss these issues systematically. The results suggest: (i) AEs have typically a stronger interest in climate change mitigation than EMDEs, (ii) from an equity perspective, compensation is called for only if EMDEs are relatively small; (iii) there can also be an efficiency case for compensation, however, with AEs buying EMDEs out of some of their GHG emissions; (iv) ultimately, a superior option—for both the world’s climate and growth prospects—is the development of clean energy technologies by AEs and their transfer to EMDEs. The latter requires strong mitigation efforts by AEs even if EMDEs fail to play along initially.