Weight Factors in Cost-Benefit Analysis of Climate Change

Equity considerations may justify the use of weight factors when estimating the costs of climate change. This paper reviews different weight factors that have been used in the climate economics literature. Based on a simple model, it is shown that although the different weight factors imply substantially different cost-damage estimates, they actually yield the same optimal emission reductions. This paradox is explained by the fact that some of the approaches require that also the abatement costs are weighted – and this offsets the effect of the diverging cost-damage estimates. The model is then used to analyse the importance weighting may have on the overall cost-benefit analysis. At present, when most of the global emissions of (fossil) CO2 originate from the industrialised countries, the global optimal emissions are considerably lower if costs are weighted. However, the more the emissions in developing countries grow, the less important becomes the introduction of weight factors in cost-benefit analysis of climate change for the global emission reductions, in the model developed here. On a regional level, the introduction of weight factors continues to play an important role, implying substantially lower emissions in the rich region and slightly higher (!) in the poor.     

Climate Policy,Learning, and Technology Adoption in Small Countries

A significant reduction in global greenhouse gas emissions requires international cooperation in emission abatement as well as individual countries’ investment in the adoption of abatement technology. The existing literature on climate policy pays insufficient attention to small countries, which account for a substantial proportion of global emission. In this study, we investigate how climate policy and learning about climate damage affect investment in abatement technology in small countries. We consider three alternative climate policy instruments: emission standards, harmonized taxes and auctioned permits. We say that learning is feasible if an international environmental agreement (IEA) is formed after the resolution of uncertainty about climate damage. We find that, either with learning and quadratic abatement costs or without learning, harmonized taxes outperform emission standards and auctioned permits in terms of investment efficiency. Without learning, a large cost of nonparticipation (that a country incurs) in the IEA can be beneficial to the country. Whether learning improves investment efficiency depends on the size of this nonparticipation cost.     

The Impact of Equity-preferences on the Stability of International Environmental Agreements

This paper uses a coalition formation model to explore how equity considerations affect countries’ cooperation on global environmental issues, e.g. on climate change. When developing countries are exempted from obligations to reduce their emissions, I find that opening them for abatement projects financed by industrialized countries changes the incentives to cooperate in a way which can increase emissions and decrease welfare. Equity- concerns in industrialized countries regarding the difference between their per capita emission levels and those of developing countries lead to increased abatement but do not qualitatively change the incentives to cooperate. Inequality-aversion with respect to differences to abatement targets across industrialized countries generally induces larger coalition sizes and stricter abatement. Here, the inclusion of developing countries improves upon the prospects of cooperation.     

Endogenous technology and tradable emission quotas

We study an international climate agreement that assigns emission quotas to each participating country. Unlike the simplest models in the literature, we assume that abatement costs are affected by R&D activities undertaken in all firms in all countries, i.e. abatement technologies are endogenous. In line with the Kyoto agreement we assume that the international climate agreement does not include R&D policies. We show that for a second-best agreement with heterogeneous countries, marginal costs of abatement differ across countries. In other words, the second-best outcome cannot be achieved if emission quotas are tradable.     

Strategic Investment in Climate Friendly Technologies: The Impact of Global Emissions Trading

Our point of departure is that a group of industrialized countries invest in research and development (R&D) of greenhouse gas (GHG) abatement technologies. R&D investments influence the future GHG abatement choices of both industrialized and developing countries. We distinguish between investments that reduce industrialized countries’ abatement costs and investments that reduce developing countries’ abatement costs. Unlike earlier contributions, we include global trading in emission permits. This changes the nature of the game. With global permit trading, industrialized countries should in many cases invest strategically in technologies that only reduce abatement costs at home. This comes in addition to investments abroad. Second, we show that R&D investments always decrease total emissions. Finally, we find that the developing region receiving investments always benefits.     

Who Should Abate Carbon Emissions? A Note

Economists commonly believe that failure to equalize the marginal cost of carbon abatement across countries implies a loss of global efficiency. Chichilnisky and Heal [(1994), Economic Letters 44, 444] first challenged this consensus a decade ago, demonstrating that, in general, efficiency does not require equalizing marginal abatement costs. This note revisits that important debate. It provides the missing intuition behind Chichilnisky and Heal’s surprising result, explains what critical assumption gives rise to their result, and clarifies the role a social welfare function plays in their model. The implications of Chichilnisky and Heal’s result are increasingly important, given international debate over the preferential role given to developing countries in the Kyoto Protocol and the role those countries will play in future climate negotiations.     

On the fair division of greenhouse gas abatement cost

This paper introduces a solution for the fair division of emission reduction costs in the climate change regime. Our primary focus is on the fair division of efficiency gains that arise from exchanging the initial allocation of emission entitlements, rather than the initial allocation itself. We propose to complement the competitive Walrasian solution with welfare bounds, the ethical justification of which rests on commonality of ownership. Simulations with an intertemporal computable general equilibrium model illustrate the relevance of such welfare bounds. For a wide range of initial allocations of emission entitlements – including an equal per capita allocation – we find that developing countries should be fully compensated for their emission abatement efforts, but should not receive any further transfers.     

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.     

Comparative assessment and essential analysis on new international GHG emission reduction proposals

Since Kyoto Protocol came into force on February 16, 2005, the endeavor by international society to combat the climate change has stepped into a new milestone. The greenhouse gas （GHG） abatement mechanisms in Kyoto Protocol have served a remarkable function but also been questioned during the practices of past three years about its environmental effectiveness. A lot of new international GHG emission reduction proposals are proposed from many new a.spects, some of which especially impose pressure on developing countries. So it is of great importance to research on these new proposals in time for negotiation beyond Kyoto and institution of Chinese relevant climate policies. As this paper focutses on the way of commitment distribution of mechanisms, the mechanisms here are categorized in one of two types： those distribute commitment based on countries and those based on sectors. Some of the typical mechanisms are selected to be analyzed comparatively, especially about their influence on developing countries,E-mail address： jiangdongmei@tsinghua.edu.cn     

Climate Policy,Uncertainty, and the Role of Technological Innovation

We study how uncertainty about climate change severity affects the relative benefits of early abatement and a portfolio of research and development (R&D) in lowering future abatement costs. Optimal early abatement depends on the curvature of the marginal benefit and marginal abatement cost (MAC) functions and how the uncertain parameter affects marginal benefits. R&D in a particular technology depends on whether uncertainty increases early abatement; whether investment lowers marginal costs for that technology; whether R&D lowers the slope of that technology's MAC function; and the shape of that technology's MAC function. We illustrate, focusing on the role of backstop technologies.     

Games of Climate Change with International Trade

We analyse games of greenhouse gas emission reduction in which the emissions and the emission reduction costs of one country depend on other countries' emission abatement. In an analytically tractable model, we show that international trade effects on costs and emissions can either increase or decrease incentives to reduce emissions and to cooperate on emission abatement; in some specifications, optimal emission reduction is unaffected by trade. We therefore specify the model further, calibrating it to larger models that estimate the costs of emission reduction, trade effects, and impacts of climate change. If trade effects are driven by total emission reduction costs of other countries cooperation is slightly more difficult than in the case without trade effects. If trade effects are determined by relative emission reduction efforts in other countries, cooperation becomes easier. Carbon leakage does not affect our qualitative insights, although it does change the numbers.     

Long-Run Implications for Developing Countries of Joint Implementation of Greenhouse Gas Mitigation

Joint Implementation (JI) calls for cooperation between industrialized and developing countries in the mitigation of greenhouse gas (GHG) emissions. However, a major concern of potential host countries is that, if they utilize their low-cost options for JI now, they will be left with only high cost options in the future, thereby penalizing them at a time when they may be obligated to mitigate GHGs themselves. This paper formalizes this hypothesis by utilizing an optimal control framework analogous to the Hotelling model of non-renewable resource extraction. The results are that cumulative abatement effects can impose costs on the future, but that they can be offset by technological change, market power, or compensation.     

Using Non Market Valuation to Inform the Choice Between Permits and Fees in Environmental Regulation

The purpose of this short note is to open an exploration regarding the use of non market valuation to help guide the selection of economically efficient pollution control instruments. As long as non market valuation techniques can correctly estimate the slope of the marginal benefit of abatement curve, this information along with engineering cost estimates of the unit costs or slope of the marginal abatement cost will provide useful information to policy makers in choosing between fees and permits. An illustrative review of the literature suggests that both stated and revealed preference methods have estimated slopes of marginal benefit functions for reducing several pollutants. To investigate the efficiency of permits versus fees, an illustrative review of corresponding marginal abatement costs is also made. For air pollutants affecting visibility, the slope of the marginal benefit curve is far greater than the slope of the marginal abatement costs, suggesting permits as the efficient instrument. For nitrates in groundwater used for drinking, the marginal benefit curve is flatter than the rather steep marginal abatement cost, suggesting fees/taxes would be a more efficient economic instrument. We hope this note stimulates more emphasis in non market valuation on estimating the slope of the marginal benefit function to enhance environmental economists ability to make policy recommendations regarding the choice of pollution instruments for specific pollutants.      

Shadow prices, environmental stringency, and international competitiveness

Empirical tests of the relationship between international competitiveness and the severity of environmental regulations are hampered by the lack of pollution abatement cost data for non-U.S. countries. The theory of the firm suggests that environmental stringency can be measured by the difference between a polluting input's shadow price and its market price. We make a first attempt at quantifying such a measure for two industries located in nine European OECD countries. Overall, we provide (i) a new approach to measure cross-country regulatory differences in that we use a theoretically attractive measure of industry-specific private compliance cost, and (ii) empirical estimates that are an attractive tool for researchers and policymakers who are interested in examining how economic activity is influenced by compliance costs.     

Industry-level emission trading between power producers in the EU

This paper investigates how restrictions for emission trading to the energy-intensive power sector will affect the magnitude and distribution of abatement costs across EU countries vis-à-vis a comprehensive EU emission trading regime. It is found that emission trading between European power sectors allows the harvest of a major part of the efficiency gains provided by full trade as compared to strictly domestic action. However, trade restrictions may create a more unequal distribution of abatement costs across member states than is the case for a comprehensive trade regime. The reason for this is that restricted permit trade enhances secondary terms-of-trade benefits to EU member countries with low marginal abatement costs at the expense of the other EU member states.     

Time Preference, Stock Externalities and Strategic Reactions

This paper examines the relationship between the rateof time preference and strategic reactions in dealing with climate change caused by anthropogenic greenhouse gas (GHG) emissions. Treating climate change as stock externalities, the RICE model (Nordhaus and Yang [1996]) is employed in this paper for simulation studies. The simulation results show that when regions' rate of time preference in evaluating climatechange is sufficiently low, the paths of efficient GHGemission reduction measurement and the inefficient Nash equilibrium outcome are close. The paper also provides general interpretations of such phenomena. Finally, the implications of a low rate of time preference on GHG emission reduction policies are discussed.     

Environmental Funds,Public Abatement,and Welfare

This paper addresses some features of environmental funds that the government uses to finance public abatement with pollution tax revenue or tariff revenue. I find that when the pollution tax rate and the tariff rate are jointly chosen optimally, then the optimal pollution tax rate is higher than the Pigouvian tax rate under public abatement financed by tariff revenue, and lower when public abatement is financed by pollution tax revenue. Furthermore, I show that the optimal tariff rate is positive regardless of which tax revenue is used to finance public abatement. These results are relevant for countries where the government seeks revenues earmarked for the financing of environmental funds.     

The Replacement Value of Wetlands in Sweden

Wetlands, in Sweden and elsewhere, have been suggestedas effective and low-cost sinks for agriculturalpollution. This paper estimates the value of usingwetlands for abatement of agricultural nitrogen loadon the Baltic Sea. A replacement value of wetlands isestimated for Sweden. The replacement value is definedand estimated as the difference between twocost-effective reductions of agricultural nitrogenpollution: one that uses wetlands for nitrogenabatement, and one that does not. It is shown that theuse of wetlands as nitrogen sinks can reduce the totalabatement costs of nitrogen emissions by 30% forSwedish agricultural sources of nitrogen pollution.     

Epstein–Zin Utility in DICE: Is Risk Aversion Irrelevant to Climate Policy?

Climate change involves uncertain probabilities of catastrophic risks, and very longterm consequences of current actions. Climate economics, therefore, is centrally concerned with the treatment of risk and time. Yet conventional assumptions about utility and optimal economic growth create a perverse connection between risk aversion and time preference, such that more aversion to current risks implies less concern for future outcomes, and vice versa. The same conflation of risk aversion and time preference leads to the equity premium puzzle in finance. A promising response to the equity premium puzzle, the recursive utility of Epstein and Zin, allows separation of risk aversion and time preference—at the cost of considerable analytic complexity. We introduce an accessible implementation of Epstein–Zin utility into the DICE model of climate economics, creating a hybrid “EZ-DICE” model. Using Epstein–Zin parameters from the finance literature and climate uncertainty parameters from the science literature, we find that the optimal climate policy in EZ-DICE calls for rapid abatement of carbon emissions; it is similar to standard DICE results with the discount rate set to equal the risk-free rate of return. EZ-DICE solutions are sensitive to the intertemporal elasticity of substitution, but remarkably insensitive to risk aversion. Insensitivity to risk aversion may reflect the difficulty of modeling catastrophic risks within DICE. Implicit in DICE are strong assumptions about the cost of climate stabilization and the certainty and speed of success; under these assumptions, risk aversion would in fact be unimportant. A more realistic analysis will require a subtler treatment of catastrophic climate risk.     

OMITTED VARIABLES, CONFIDENCE INTERVALS, AND THE PRODUCTIVITY OF EXCHANGE RATES

Abstract.  A new analytical technique, named 'Bi-Directional Reiterative Truncated Projected Least Squares' (BD-RTPLS), produces reduced form estimations and less than half the error of OLS when there are omitted variables that interact with included variables. This paper develops confidence intervals for BD-RTPLS and uses BD-RTPLS to estimate the relationship between the exchange rate (e) and gross domestic product (GDP) using annual data from 1984 to 2000 for 23 developing Asian and Pacific countries. BD-RTPLS produces estimates for the exchange rate multiplier ( d GDP/ d e) for these countries and shows how omitted variables affected these multipliers across countries and over time.