International capital markets,oil producers and the Green Paradox

A rapidly rising carbon tax leads to faster extraction of fossil fuels and accelerates global warming. We analyze how general equilibrium effects operating through the international capital market affect this Green Paradox. In a two-region, two-period world with identical homothetic preferences and without investment, the global interest rate falls and the Green Paradox weakens. With investment or a relatively more impatient oil-importing region, the Green Paradox may be strengthened because the future oil demand function shifts downward or because the interest rate rises. If the oil-importing region is very much more patient than the oil-exporting region, the Green Paradox may be reversed but in our calibrated model the effects are tiny. With exploration and endogenous initial oil reserves, a future carbon tax lowers cumulative oil extraction in partial equilibrium. If the boost to current oil extraction is weakened, strengthened or reversed in general equilibrium, so is the fall in cumulative extraction. A partial and general equilibrium welfare analysis of a future carbon tax, both for full and partial exhaustion, is given. The effects of stock-dependent extraction costs are separately discussed in an Appendix.     

Second-Best Renewable Subsidies to De-carbonize the Economy: Commitment and the Green Paradox

Climate change must deal with two market failures: global warming and learning by doing in renewable energy production. The first-best policy consists of an aggressive renewables subsidy in the near term and a gradually rising and falling carbon tax. Given that global carbon taxes remain elusive, policy makers might have to rely on a second-best subsidy only. With credible commitment the second-best subsidy is higher than the social benefit of learning to cut the transition time and peak warming close to first-best levels at the cost of higher fossil fuel use in the short run (weak Green Paradox). Without commitment the second-best subsidy is set to the social benefit of learning. It generates smaller weak Green Paradox effects, but the transition to the carbon-free takes longer and cumulative carbon emissions are higher. Under first best and second best with pre-commitment peak warming is 2.1–2.3 \(^{\circ }\)C, under second best without commitment 3.5 \(^{\circ }\)C, and without any policy 5.1 \(^{\circ }\)C above pre-industrial levels. Not being able to commit yields a welfare loss of 95% of initial GDP compared to first best. Being able to commit brings this figure down to 7%.     

Output‐based rebating of carbon taxes in a neighbour's backyard: Competitiveness,leakage and welfare

We investigate how, in an open economy, carbon taxes combined with output‐based rebating (OBR) perform in interaction with the carbon policies of a large neighbouring trading partner. Analytical results suggest that, whether the purpose of the OBR policy is to compensate firms for carbon tax burdens or to maximize welfare (accounting for global emission reductions), the OBR rate should be positive in policy‐relevant cases. Numerical simulations for Canada, with the US as the neighbouring trading partner, indicate that the impact of US policies on the OBR rate will depend crucially on the purpose of the Canadian OBR policies. If, for a given US carbon policy, Canada's aim is to restore the competitiveness of domestic emission‐intensive and trade‐exposed (EITE) firms to the same level as before the introduction of its own carbon taxation, we find that the necessary domestic OBR rates will be insensitive to the foreign carbon policies. However, if not only the Canadian carbon tax but also an equally high US tax is introduced, compensatory Canadian OBR rates will be up to 50% lower, depending on the sector and on US OBR policy. If the policy objective is to increase economy‐wide allocative efficiency (welfare) of Canadian policies by accounting for carbon leakage, the US policies will have only a minor downward pressure on desirable OBR rates in Canada. Practical choices of OBR rates hardly affect overall domestic economic performance; thus, output‐based rebating qualifies as an instrument for compensating EITE industries without a large sacrifice in terms of economy‐wide allocative efficiency.     

Border carbon adjustments and unilateral incentives to regulate the climate

It is suggested that trade measures should be used to induce exporters to adopt more ambitious climate policy and reduce global emissions. However, a tariff and the exporter's emission tax are likely substitutes, which would undermine the rationale for these trade measures. This paper examines incentives to regulate the climate under border carbon adjustment (BCA), defined as an import duty of a magnitude determined by the difference in emission taxes between trade partners. Unlike a tariff, a BCA can induce the exporter to adopt a higher tax, suggesting that the BCA and tariff are not equally effective at targeting global emission levels and that the features of the border measure matter in assessing the effectiveness of trade policy in targeting global emissions.     

Climate Policy under Technology Spillovers

We study climate policy when there are technology spillovers between countries, as there is no instrument that (directly) corrects for these externalities. Without an international climate agreement, the (non-cooperative) equilibrium depends on whether countries use tradable quotas or carbon taxes as their environmental policy instruments. All countries are better-off in the tax case than in the quota case. Two types of international climate agreements are then studied: One is a Kyoto type of agreement where each country is assigned a specific number of internationally tradable quotas. In the second type of agreement, a common carbon tax is used domestically in all countries. None of the cases satisfy the conditions for the social optimum. Even if the quota price is equal to the Pigovian level, R&D investments will be lower than what is socially optimal in the quota case. It is also argued that the quota agreement gives higher R&D expenditures and more abatement than the tax agreement.     

When does a carbon tax on fossil fuels stimulate biofuels?

A carbon tax is an efficient economic instrument to reduce emissions of carbon dioxide released from fossil fuel burning. If designed properly, it could also help significantly to promote renewable energy. Using a multi-sector, multi-country computable general equilibrium model this study investigates under what circumstances a carbon tax would help stimulate penetration of biofuels into the energy supply mix for road transportation in various countries and regions around the world. This study shows that a carbon tax cum biofuel subsidy policy, where a carbon tax is introduced to fossil fuels and part of the tax revenue is used to finance the biofuel subsidy, would significantly help stimulate market penetration of biofuels. On the other hand, a carbon tax alone policy, where the entire tax revenue is recycled to households through a lump-sum transfer, does not help stimulate biofuels significantly even at higher tax rates. Although the carbon tax cum subsidy policy would cause higher loss in economic output at the global level as compared to the carbon tax alone policy, the incremental loss is relatively small. The key policy insight drawn from the study is that if a carbon tax were to be implemented in an economy for the purpose of climate change mitigation, recycling part of its revenue to finance biofuel subsidies would significantly help stimulate biofuels.     

Radiative forcing and the optimal rotation age

Forests help mitigate climate change by sequestering atmospheric carbon. However, boreal and high-latitude temperate forests may also contribute to global warming due to the albedo effect. The relative effects of carbon sequestration and albedo can be quantified in terms of radiative forcing. We present a stylized, stand-level analysis to determine the optimal rotation age when considering a tax/subsidy scheme based on radiative forcing and the notion of equivalent carbon emissions. Additional management decision variables considered include species choice and regeneration effort, since these can impact the albedo effect. We demonstrate analytically that the optimal rotation length is likely shortened when albedo-related equivalent emissions are incorporated, relative to a policy based only on carbon. Empirical results indicate that rotation ages do decrease relative to a “carbon only” policy, and approach the traditional (timber only) Faustmann rotation age as equivalent emission rates increase. Our results suggest that forestation does not necessarily provide climatic benefits in all circumstances, and that, at the margin, other opportunities for carbon reduction (e.g. abatement), or pursuing forestation in other locations, become more attractive.     

Corporate social responsibility,stock prices,and tax policy

We model a market in which some investors get utility from owning shares of firms that engage in corporate social responsibility (CSR). In equilibrium, investors' CSR considerations influence portfolio choices, stock prices, and CSR spending. We study tax policy designed to maximize total giving (individual and corporate) net of government tax breaks and find that its effectiveness is non‐monotonic in the proportion of altruistic investors: with few or many altruistic investors, it has little impact on giving, but, at intermediate levels, effective tax policy intuitively relates the corporate tax rebate rate on giving and the cap on allowable tax savings.     

Climate Policy Under Fat-Tailed Risk: An Application of Dice

Uncertainty plays a significant role in evaluating climate policy, and fat-tailed uncertainty may dominate policy advice. Should we make our utmost effort to prevent the arbitrarily large impacts of climate change under deep uncertainty? In order to answer to this question, we propose a new way of investigating the impact of (fat-tailed) uncertainty on optimal climate policy: the curvature of the optimal carbon tax against the uncertainty. We find that the optimal carbon tax increases as the uncertainty about climate sensitivity increases, but it does not accelerate as implied by Weitzman’s Dismal Theorem. We find the same result in a wide variety of sensitivity analyses. These results emphasize the importance of balancing the costs of climate change against its benefits, also under deep uncertainty.     

“More is less”: the tax effects of ignoring flow externalities

Using a model of non-linear, non-monotone decay of the stock pollutant, and starting from the same initial conditions, the paper shows that an optimal tax that corrects for both stock and flow externalities may result in a lower tax, fewer cumulative emissions (less decay in emissions) and higher output at the steady state than a corrective tax that ignores the flow externality. This “more is less” result emphasizes that setting a corrective tax that ignores the flow externality, or imposing a corrective tax at too low a level where there exists only a stock externality, may affect both transitory and steady-state output, tax payments and cumulative emissions. The result has important policy implications for decision makers setting optimal corrective taxes and targeted emission limits whenever stock externalities exist.     

Oil shocks,policy uncertainty and stock returns in China

This paper examines the interdependence of China's policy uncertainty, the global oil market and stock market returns in China. A structural VAR model is estimated that shows that a positive shock to economic policy uncertainty in China has a delayed negative effect on global oil production, real oil prices and real stock market returns. Shocks to oil market‐specific demand significantly raise China's economic policy uncertainty and reduce the real stock market returns. As measured by a spillover index, the interdependence between these variables has been rising since 2003 as China's influence in the oil market has increased. An equivalent spillover index calculated for the US is smaller and has been largely flat over time.     

Using a Real‐Options Approach to Model Technology Adoption Under Carbon Price Uncertainty: An Application to the Australian Electricity Generation Sector*

The present climate for investment in electricity generation assets in Australia is uncertain. We develop a real‐options model to contrast the timing of the uptake of various electricity generation technologies under two carbon tax simulations: when a carbon tax of known size commences at a certain date in the future; and a carbon tax of known size commences at an uncertain date in the future. We find that uptake in the future varies significantly depending upon an investor's view of uncertainty and whether the technology is primarily designed to be viable in a market with or without carbon taxes.     

欧盟碳税政策的经验与启示

随着全球气候变化带来的恶劣影响进一步加剧,减缓和适应气候变化已成为世界各国所关心的重要议题。越来越多的国家采取了各种温室气体减排措施,征收碳税就是其中之一。目前欧盟一些国家已实行碳税,并取得了一定的效果。以芬兰、丹麦、瑞典和英国为例,对这四个国家的碳税情况进行比较分析,以期对中国有所启示。     

Who Pays a Price on Carbon?

We use the 2003 Consumer Expenditure Survey and emissions estimates from an input-output model based on the 1997 US economy to estimate the incidence of a price on carbon induced by a cap-and-trade program or carbon tax in the context of the US. We present results on how much different income deciles pay for a carbon tax as well as which industries see the largest increase in costs due to a carbon tax. We illustrate the main determinant of the regressivity: consumption patterns for energy-intensive goods. Furthermore, on a per-capita basis a carbon price is much more regressive than calculations at the household level. We discuss policy options to offset the adverse distributional effects of a carbon emissions policy.     

How should the use of nonrenewables be taxed under a public budget constraint?

Most developed countries will be facing severe public budget constraints. We examine how extraction or use of nonrenewable resources should be taxed when governments need to collect commodity tax revenues. Moreover, we show how our results can be directly used to indicate how carbon taxation of nonrenewable energy sources should be increased in the presence of public-revenue needs. The obtained tax formula is an augmented, dynamic version of the standard Ramsey taxation rule. It distorts developed reserves, which are reduced, and their depletion, which is slowed down, going further in the direction prescribed for the resolution of the climate externality. We present a simple calibrated application of our results to illustrate how carbon taxation of oil should be strongly augmented, and the incidence of this adjustment on oil use and tax revenues.     

Climate change,fossil fuel prices and depletion: The rationale for a falling export tax

This paper examines how world prices affect depletion of exhaustible fossil fuels for export and the role of an export revenue tax in curbing depletion. Both effects are studied for a small open economy affected by climate change. We find that setting an export revenue tax rate to fall over time at the marginal social cost of depletion due to lower productivity from climate change encourages a resource exporter to leave an optimal stock in the ground – unextracted and unburnable. Growing prices during the past decade similarly curb depletion. Falling prices bring forward extraction. Because production is independent of consumption, the marginal social cost is independent of utility parameters which are difficult to estimate. Slowing fossil fuel extraction and the effective export of emissions is a contemporary challenge for climate policy. Our findings identify both why an export revenue tax should decline over time and an estimable target rate of decline to help meet this challenge amid changing world prices.     

Climate policy vs. agricultural productivity shocks in a dynamic computable general equilibrium (CGE) modeling framework: The case of a developing economy

The main objective of this paper is to compare the cost of climate policy consistent with the 2 °C global warming target (Paris Agreement target) with the cost of climate change induced agricultural productivity shocks, using a recursive dynamic CGE model for India. The social cost of carbon, in terms of loss in agriculture sector, is estimated to be about 2 percent of GDP, at zero rate of discount, under conservative forecasts of fall in agricultural productivity. In comparison, the cost of climate policy consistent with the Paris Agreement target of 2 °C is about 1 percent of GDP. Thus, there is a strong case for the adoption of ambitious climate policy in India, provided other countries also adhere to the same. Besides, revenues generated from the carbon tax and emission allowance could be a means to support the development and adoption of new energy and agricultural technologies, to increase social sector expenditure and to reduce abatement costs.     

Globalization, Asymmetric Tax Competition, and Fiscal Equalization

Trade integration and the increasing mobility of firms have raised the need for international coordination in corporate tax. In this paper, we study the ability of fiscal equalization to avoid the misallocation of capital across asymmetric countries arising from tax competition. Such a reform respects the principle according to which the tax decision is entirely left up to the nation and links nations engaged in strategic tax policy by transfers. We use a model of trade and location where firms produce under imperfect competition. Our analysis suggests that falling trade costs increase the distortion created by tax competition in the international allocation of production. However, we show that fiscal equalization based on differences in tax revenues or tax base can implement a more efficient tax wedge and spatial allocation of the tax base.     

Tax on emissions or subsidy to renewables? Evaluating the effects on the economy and on the environment

We examine the relationship between the economy and the environment in a model where production uses nonpolluting renewable and polluting nonrenewable resources. There is policy intervention through a tax on emissions and a subsidy to renewables extraction/production. Results show that both instruments are able to decrease emissions intensity of output. However, when used together, the desired effect is higher. Empirically it is shown that the subsidy achieves higher renewables intensity and although present emissions per output are similar for both instruments, the subsidy achieves lower future levels.     

Beyond Kyoto, plan B: A climate policy master plan based on transparent metrics

Many scholars analyze the Kyoto–Copenhagen process, and offer corrective suggestions for identified flaws in the present design. Based on various proposals in the literature, this article adopts a global master-plan perspective, leaving executive architecture to sovereign participants. Transparent, flexible and fair top-down rules must synchronize the numerous bottom-up initiatives while addressing the diversity of national circumstances in the drastic transformation of the world's energy economies.Plan B refutes absolute emission reduction targets on old or speculative baselines. It criticizes global tax and permit trade instruments for being ineffective, inefficient and unfair when uniformly applied on a tremendous differentiated world. Plan B is built on three annually observed variables measuring percentage progress against rolling baselines (the variables' values in the previous year): the ratio of net climate tax revenues to GDP, the commercial energy intensity of GDP, and the carbon intensity of commercial energy use. The three variables together indicate countries' progress affecting emissions per person, a metric that must converge to lower bands when climate change is addressed seriously. Long-term scenarios of global convergence “funnels” serve as guidance to frame near-term actions rich and poor countries individually propose to take. The global regime is common for all countries, and is ranked by GDP per person to determine whether a nation is a donor or a beneficiary in a Global Climate Transfer Fund. Fund payments and drawing rights depend on that ranking but also on the performances of the countries in realizing committed progress. The transparent mechanisms of the design and of the fund persuasively invite countries to participate in a fair, self-enforcing agreement.