Polluting Non-Renewable Resources and Growth

In an endogenous growth model with human capital accumulation, we introduce non-renewable resources which cause flow pollution problems. In this set-up the negative external effect of pollution on productivity does not cause any distortions in the economy: The market economy will achieve the optimal extraction and growth rates. Consequently, emission taxes are unnecessary and, when introduced, will have no effect on the economy. The more important is the negative pollution externality, the larger will be the optimal long-run growth rate (which may be either positive or negative). In the case of a positive human capital externality, consumption in the market economy may approach zero in the long run, although positive consumption growth is socially optimal. Growth-enhancing policies do not necessarily cause a larger drain in the resource stock.     

Climate Change Policy Options for Asian Economies: Findings from an Integrated Assessment Model

This study outlines potential futures for the global economy through the 2050 with a specific focus on the countries of Asia. With underlying assumptions about population and output growth, a baseline scenario assesses the growth of greenhouse gas emissions and the ensuing impacts on the climate. Under the baseline scenario, Asia's high growth leads to a strong rotation in global output and emissions by the year 2050. The analytical framework traces back the changes in temperature to economic damages – limited to the agricultural sectors. Parts of Asia are likely to see much higher dependence on food imports as a consequence of these damages. Various carbon tax scenarios are implemented to assess the potential for reducing carbon emissions. Because of the structure of their economies, Asian countries are likely to bear the greatest burden in reducing emissions in an efficient global tax scheme, but there is significant scope to ease this burden through financial transfers.     

The transition to an oil contraction economy

A normative analysis of the problem of optimal extraction of a nonrenewable resource is considered. The economy depends on the essential nonrenewable resource and the rate of the resource extraction is increasing over time. At some point the government gradually switches to a sustainable (in sense of non-decreasing consumption over time) pattern of the resource extraction. Different approaches are offered for the construction of the paths of switching to decreasing resource use. Some seemingly attractive short-run policies of switching to decreasing extraction can run counter to long-run criteria. If we consider the maximin principle, applied to the negative shock on the output percent change, as the short-run criterion, then the optimal transition path can be consistent with the long-run government goals. It is shown analytically and numerically that there are values of parameters for the transition paths of extraction that consumption along these paths is asymptotically constant or infinitely growing. A new approach to the Rawlsian maximin criterion which allows for growth of consumption is offered.     

低碳转型下的技术发展路径选择

通过建立一个内生技术变化的优化模型,考察了在不确定的技术学习、确定性的技术学习以及不确定的碳税3种情况下,向低碳经济转型的技术发展路径选择问题。研究表明,通过选择适当的技术发展路径,可以有效减少减排成本和碳排放,实现向低碳经济转型。技术学习是产生这种最优技术发展路径的关键因素,技术学习的不确定性会扩大不同技术发展路径之间的差异,而不确定的碳税则缩小了这些技术发展路径的差异。     

Disutility of pollution and endogenous growth

Endogenous growth is generally built on a positive externality hypothesis which is the opposite of a negative externality caused by pollution. We study a linear technology with simple assumption: an aggregate capital stock which represents a learning by doing effect and a pollution flow proportional to production. In this framework, we analyse the precise effects on growth of the disutility of pollution and its interaction with the utility of consumption in an economy without abatement technology. The decentralized equilibrium always leads to unlimited growth, but optimal growth is often limited (the negative effect of pollution dominating the positive effect of learning by doing). In this case, the optimal policy which leads the decentralized economy to follow the optimal growth path is to tax capital; in contrast with the optimal subsidy policy in an economy without pollution. When an abatement technology is introduced, the optimal solution can lead the economy to unlimited growth, whatever the form of the utility function.     

The impact of financial development,income, energy and trade on carbon emissions: Evidence from the Indian economy

This paper examines the long-run equilibrium and the existence and direction of a causal relationship between carbon emissions, financial development, economic growth, energy consumption and trade openness for India. Our main contribution to the literature on Indian studies lies in the investigation of the causes of carbon emissions by taking into account the role of financial development and using single country data. The results suggest that there is evidence on the long-run and causal relationships between carbon emissions, financial development, income, energy use and trade openness. Financial development has a long-run positive impact on carbon emissions, implying that financial development improves environmental degradation. Moreover, Granger causality test indicates a long-run unidirectional causality running from financial development to carbon emissions and energy use. The evidence suggests that financial system should take into account the environment aspect in their current operations. The results of this study may be of great importance for policy and decision-makers in order to develop energy policies for India that contribute to the curbing of carbon emissions while preserving economic growth.     

Optimal emission-extraction policy in a world of scarcity and irreversibility

This paper extends the classical exhaustible-resource/stock-pollution model with irreversibility of pollution decay, meaning that after reaching some threshold there is no decay of the pollution stock. Within this framework, we answer the question how the potential irreversibility of pollution affects the extraction path. We investigate the conditions under which the economy will optimally adopt a reversible policy, and when it is optimal to enter the irreversible region. In the case of irreversibility it may be optimal to leave a positive amount of resource in the ground forever. As far as the optimal extraction/emission policy is concerned, several types of solutions may arise, including solutions where the economy stays at the threshold for a while. Given that different programs may satisfy the first order conditions for optimality, we further investigate when each of these is optimal. We show that it is never optimal for the economy to stay at the threshold for a while before entering the irreversible region. The optimality analysis is then illustrated by means of a calibrated example. To sum up, for any pollution level, we can identify a critical resource stock such that there exist multiple optima i.e. a reversible and an irreversible policy that yield exactly the same present value. For any resource stock below this critical value, the optimal policy is reversible whereas with large enough resources, irreversible policies outperform reversible programs.     

Optimal emission-extraction policy in a world of scarcity and irreversibility

This paper extends the classical exhaustible-resource/stock-pollution model with irreversibility of pollution decay, meaning that after reaching some threshold there is no decay of the pollution stock. Within this framework, we answer the question how the potential irreversibility of pollution affects the extraction path. We investigate the conditions under which the economy will optimally adopt a reversible policy, and when it is optimal to enter the irreversible region. In the case of irreversibility it may be optimal to leave a positive amount of resource in the ground forever. As far as the optimal extraction/emission policy is concerned, several types of solutions may arise, including solutions where the economy stays at the threshold for a while. Given that different programs may satisfy the first order conditions for optimality, we further investigate when each of these is optimal. We show that it is never optimal for the economy to stay at the threshold for a while before entering the irreversible region. The optimality analysis is then illustrated by means of a calibrated example. To sum up, for any pollution level, we can identify a critical resource stock such that there exist multiple optima i.e. a reversible and an irreversible policy that yield exactly the same present value. For any resource stock below this critical value, the optimal policy is reversible whereas with large enough resources, irreversible policies outperform reversible programs.     

Fertility and climate change*

A quarter of the total increase in emissions is attributable to the growth of emissions per capita, whereas three-quarters are due to population growth. This evidence notwithstanding, demography in climate–economy models typically follows exogenous trends. We develop a climate–economy integrated model with endogenous fertility through a quality–quantity trade-off. The decentralization of the social optimum requires two complementary instruments: a carbon pricing policy and family planning interventions. Global population increases and reaches a peak, depending on the scenario, between 11.6 billion in the social optimum and 14.6 billion if only carbon prices are implemented. Fertility costs (i.e., the net present value of the climate-related costs per child) are in 2020 estimated to be about 22,000 euros in the “social optimum” scenario, and about 88,000 euros in the “second-best with fertility taxes” scenario. Carbon pricing tends to have a rebound effect as it increases population growth leading to higher future emissions. Our results highlight the effects of fertility choices and global population on climate change, quantifying the cost of neglecting the interaction.     

The optimal control of emissions and renewable resource harvesting under uncertainty

A model of a renewable resource is developed where the growth and quality of the resource are reduced by pollution. Ambient pollution concentrations and the renewable resource stock are modeled as stochastic processes. Conditions for the optimal harvest plan and the optimal emissions rate are derived. The effect of stochastic variations on the optimal management of the resource is analyzed. The steady-state joint probability distribution of the resource and pollution stocks is shown to exist under certain conditions.     

CO2 Emissions and Income Dynamics: What Does the Global Evidence Tell Us?

This paper analyzes the co-evolution of two major determinants of social welfare, namely, income and carbon emissions. In particular, by using a distribution dynamics approach based on Markov chains, we investigate the shape and behavior of the joint distribution of per-capita income and carbon dioxide emissions. We arrive at several interesting conclusions, especially in the context of international negotiations on climate change. First, evidence does not support theoretical models predicting the existence of a poverty-environment trap. Specifically, in the long-run two main groups of countries will emerge: poor versus polluting countries. Second, the typical development path leads initially to high emission levels and, subsequently, to high income. Third, the convergence process towards the stationary distribution is very slow. Finally, for carbon emissions, whenever it is observed, the environmental Kuznets curve seems to be only a transitory phenomenon.     

The trade-off between environmental care and long-term growth—Pollution in three prototype growth models

The effects of increased environmental care on optimal technology choice and long-term growth are studied for an economy in which pollution is a side-product of physical capital used in production. First, it is shown that in case of a standard neoclassical production structure, the result is a less capital-intensive production process whereas the long-run growth rate is not affected. Next, we introduce assumptions of the endogenous growth literature. When there are constant returns to physical capital, an increase in abatement activities crowds out investment and lowers the endogenous growth rate. When human capital accumulation is the engine of growth, physical capital intensity declines and the endogenous optimal growth rate is unaffected by increased environmental care or is even higher, depending on whether or not pollution influences agents' ability to learn.The authors are grateful to an anonymous referee, to Lans Bovenberg, Noud Gruijters, Theo van de Klundert, Lex Meijdam, and Sweder van Wijnbergen for helpful and stimulating comments. The views expressed in this paper are the authors' own and should not be attributed to the Ministry of Finance.     

Optimal unemployment insurance: transitional dynamics vs. steady state

In this study, we ask whether the presence of precautionary savings substantially reduces the optimal replacement rate in an European economy type characterized by high unemployment benefits and moral hazard. We build a simple job search model calibrated on French data and, in line with previous studies, find that the optimality criterion based on comparisons of steady states leads to a low optimal ratio. Yet, this result ignores potential transitional costs due to the necessity for agents to increase their savings and reduce their consumption whenever the ratio is cut. We therefore build a dynamic model taking full account of the transition, and show that a reduction in benefits reduces welfare. Even though the long-run optimal replacement rate is lower than the current one, transitional costs dominate long-run gains.     

How should environmental policy respond to business cycles? Optimal policy under persistent productivity shocks

How should environmental policy respond to economic fluctuations caused by persistent productivity shocks? This paper answers that question using a dynamic stochastic general equilibrium real business cycle model that includes a pollution externality. I first estimate the relationship between the cyclical components of carbon dioxide emissions and US GDP and find it to be inelastic. Using this result to calibrate the model, I find that optimal policy allows carbon emissions to be procyclical: increasing during expansions and decreasing during recessions. However, optimal policy dampens the procyclicality of emissions compared to the unregulated case. A price effect from costlier abatement during booms outweighs an income effect of greater demand for clean air. I also model a decentralized economy, where government chooses an emissions tax or quantity restriction and firms and consumers respond. The optimal emissions tax rate and the optimal emissions quota are both procyclical: during recessions, the tax rate and the emissions quota both decrease.     

Optimal Investment in Clean Production Capacity

For the mitigation of long-term pollution threats, one must consider that both the process of environmental degradation and the switchover to new and cleaner technologies are dynamic. We develop a model of a uniform good that can be produced by either a polluting technology or a clean one; the latter is more expensive and requires investment in capacity. We derive the socially optimal pollution stock accumulation and creation of nonpolluting production capacity, weighing the tradeoffs among consumption, investment and djustment costs, and environmental damages. We consider the effects of changes in the pollution decay rate, the capacity depreciation rate, and the initial state of the environment on both the steady state and the transition period. The optimal transition path looks quite different with a clean or dirty initial environment. With the former, investment is slow and the price of pollution may overshoot the long-run optimum before converging. With the latter, capacity may overshoot.     

黑龙江省碳排放与经济增长——基于协整分析和格兰杰因果检验

采用协整分析、格兰杰(Granger)因果关系检验,利用黑龙江省1990～2009年GDP和碳排放总量的时间序列数据,对黑龙江省碳排放与经济增长的关系进行了实证分析,得出黑龙江省碳排放与经济增长存在长期均衡关系,且碳排放是经济增长的格兰杰原因。     

Fiscal Policy, Congestion, and Endogenous Growth

We devise an endogenous growth model with private and public physical capital, and human capital, which allows for relative and absolute congestion. According to empirical evidence, long-run growth is invariant to fiscal policy. Despite its complexity, the dynamics of the market economy and the centralized economy are analyzed in detail. We show that an increase in absolute congestion reduces the long-run growth rate of output. In contrast, relative congestion does not affect long-run growth. In the absence of congestion, it is optimal to use lump-sum taxation, and with congestion it is optimal to also tax income.     

Gradual Product Replacement,Intangible-Asset Prices and Schumpeterian Growth

The paper develops a general-equilibrium model of scale-invariant Schumpeterian (R&D-based) growth. New higher-quality products are discovered through stochastic and sequential R&D races in each industry. The market share of an R&D race winner increases gradually and is governed by an exponential deterministic process. The introduction of gradual (as opposed to instantaneous) product replacement sheds more light on the effects of the rate of technology diffusion on long-run growth and on long-run dynamics of intangible asset prices. An economy with faster product diffusion rates experiences higher long-run innovation rates, faster transitional growth, and is populated by younger firms. As the typical firm becomes older, the earnings yield (i.e., the inverse of the price earnings (P/E) ratio) increases and expected earnings growth declines. Younger firms have lower earnings, lower market shares, but higher P/E ratios and higher expected earnings growth associated with their higher potential market growth.An electronic version of the paper is available at http://bear.cba.ufl.edu/dinopoulos/research.html.     

How do market reforms affect China's responsiveness to environmental policy?

A large percentage of total investment in China is allocated by the central government at below-market interest rates in pursuit of non-economic objectives. This has resulted in low rates of return and a high number of non-performing loans, threatening the future health of the Chinese economy. As a result, reform of capital markets is a high priority of the Chinese government. At the same time, the country is implementing various environmental policies to deal with serious pollution issues. In this paper we ask how reforms of the capital market will affect the functioning of a carbon tax. This allows us to assess how China's willingness to join global efforts to reduce carbon emissions is influenced by China's current efforts to reduce investment subsidies. We compare the costs of a carbon tax in a reformed economy with the costs of a carbon tax in the current subsidized economy. We find that in the subsidized economy the tax-interaction effect dampens the effect of a carbon tax resulting in smaller reductions in emissions than what would result in a reformed economy. Importantly, we also find that the effect on economic welfare from a carbon tax is lower in the subsidized economy; in fact, for lower levels of reductions, the carbon tax is actually welfare improving. These results have important implications for an economy undergoing economic transition. The carbon tax rate required to achieve a certain level of emission reductions will be higher in an economy with capital subsidies. However, the welfare implications of the tax indicate that the current system with capital subsidies is highly distorting implying that there is a high efficiency cost for the non-economic objectives the government is pursuing by maintaining this system of subsidies.     

Reconsidering the Impact of the Environment on Long-run Growth when Pollution Influences Health and Agents have a Finite-lifetime

Using an overlapping generation model à la Blanchard (1985, J Polit Econ 93:223–247) with human capital accumulation, we demonstrate that the influence of the environment on optimal growth in the long-run may be explained by the detrimental effect of pollution on life expectancy. We also show that, in such a case, greener preferences are growth- and welfare-improving in the long-run even if the ability of the agents to learn is independent of pollution and utility is additively separable. Finally, we establish that a minimum environmental policy is required to obtain a sustainable equilibrium in the market economy and that it is possible to implement a win–win environmental policy.