2012年-IMF国际货币组织全球_Coordinating_Climate_and_Trade_Policies_Pareto_Efficiency_and_the_Role_of_Border_Tax_Adjustments_26页_890kb

Summary of "Coordinating Climate and Trade Policies: Pareto Efficiency and the Role of Border Tax Adjustments"

Core Content

This paper examines the role of border tax adjustments (BTAs) in achieving Pareto-efficient climate and trade policies when carbon prices differ across countries. It uses a general equilibrium model with international trade and a climate-like production externality to explore the conditions under which BTAs are necessary or beneficial for global efficiency.

Main Viewpoints

• Carbon leakage is a major concern for countries implementing carbon pricing, as it may lead to a loss of competitiveness due to production shifting to countries with lower carbon prices.
• Pareto efficiency is central to the analysis. It implies that no country should be made worse off by a policy change, and that the policy should be efficient in terms of both climate outcomes and distributional concerns.
• The efficiency of BTA depends on whether carbon taxation or cap-and-trade is used for climate policy. The paper emphasizes that the case for BTA is stronger under carbon taxation than under cap-and-trade.
• Tariffs play a role in addressing distributional issues when carbon prices are not uniform globally. In particular, BTA can help internalize the international distribution of carbon pricing impacts.

Key Information

I. Introduction

• Countries concerned about carbon leakage are increasingly considering border tax adjustments (BTAs) to protect their competitive position.
• The paper argues that the efficiency case for BTA is not well understood in policy debates, and that it is crucial to assess it in the context of cooperative policy design.
• The focus is on Pareto efficiency, which requires that carbon taxes and tariffs be set in a way that no country is worse off while achieving global climate goals.

II. Modeling Climate and Trade Policies

• The model is based on Keen and Wildasin (2004), extended to include climate-related production externalities.
• There are J countries, each with a representative consumer and a private sector producing N tradeable commodities.
• Commodity prices in each country are given by the world prices plus tariffs.
• Carbon taxes and tariffs are used to internalize externalities and adjust for distributional concerns.
• International transfers are allowed and used to equalize welfare across countries.

III. The Benchmark: Unconstrained Carbon Tax and Tariff Policies

• Proposition 1 outlines the conditions for Pareto efficiency when carbon taxes and tariffs are unconstrained.
  • (a) Carbon taxes in each country are proportional to the sum of marginal environmental benefits across all countries.
  • (b) Tariff vectors are collinear across countries, meaning that the tariff rate in one country is a multiple of the tariff rate in another.
• Pareto efficiency requires equalizing carbon taxes and tariffs across countries if international transfers are unrestricted.
• In such a case, tariffs are redundant as they do not affect production efficiency or climate outcomes.
• Carbon taxes are set at the first-best Pigovian level, which internalizes the external cost of emissions.

IV. Pareto Efficiency and the Role of Border Tax Adjustments

• Proposition 3 considers the case where carbon taxes and tariffs are fixed in one country (country 2), and unconstrained in another (country 1).
  • (a) The carbon tax in the unconstrained country is set to reflect the global marginal environmental benefits.
  • (b) The tariff in the unconstrained country is set to adjust for the difference in carbon prices between the two countries, acting as a form of BTA.
• The BTA in this context is a tariff on imports and a refund on exports, which reflects the difference in carbon taxes between countries.
• The efficiency of BTA depends on the impact of carbon prices on emissions and the price elasticity of net imports in the constrained country.
• If carbon prices in the constrained country have no effect on emissions, the case for BTA disappears.

V. Further Discussion

• The paper compares the cooperative and non-cooperative policy frameworks, showing that Pareto efficiency requires different policy instruments than non-cooperative outcomes.
• The role of BTA is more pronounced when carbon taxation is used rather than cap-and-trade.
• International transfers can be used to equalize welfare, but they are not always necessary if tariffs can be adjusted to achieve the same effect.

Conclusion

• The paper concludes that BTA is necessary in situations where carbon taxes are constrained and tariffs are the only available instrument to achieve Pareto efficiency.
• The efficiency of BTA depends on the structure of carbon pricing and the distribution of welfare weights across countries.
• The results are unified and extended from previous literature on the link between climate and trade policies.
• The simple BTA structure, as commonly discussed in policy debates, is justified under certain conditions and is likely the only practicable form of BTA.

Key Terms

• Pareto efficiency: A state where no individual or country can be made better off without making someone else worse off.
• Border tax adjustment (BTA): A policy that adjusts tariffs based on differences in carbon prices between countries.
• Carbon taxation: A policy that imposes taxes on carbon emissions to internalize the climate externality.
• Cap-and-trade: A market-based policy that sets a limit on total emissions and allows trading of emission permits.
• International transfers: Financial transfers between countries to equalize welfare.

Implications

• BTAs can be an effective tool in coordinating climate and trade policies when carbon taxes are constrained.
• Tariffs may be necessary to address distributional concerns and ensure Pareto efficiency.
• Carbon taxation is more aligned with the efficiency case for BTA than cap-and-trade.
• The analysis highlights the complex interplay between climate policy, trade policy, and international equity.