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This commentary expounds on the obstacles and tensions introduced by Grewal, Guha, and Becker using a neo-colonialist perspective to examine the impact of Artificial Intelligence (AI) development as it related to non-renewable resources, datasets and labeling, and global labor exploitation. [ABSTRACT FROM AUTHOR]

Disruptions in the minerals supply chain play a central role in defining the future stock of minerals; therefore, an in-depth analysis of the outcomes and variables affecting exploration is required. In comparative terms, the exploration of critical minerals and major minerals presents geological and technical differences; thus, exploration budgets for critical minerals should be expected to depart from those observed in other minerals. In this context, the main goal of this paper is to contrast how exploration budgets differ between critical and major minerals when considering a set of key variables. We take a multivariate statistical analysis approach based on firm-level budget exploration data to show four key findings: exploration budgets allocated for critical minerals remain consistently lower than major minerals even when controlling for other factors. Moreover, they present a higher sensitivity to fluctuations in commodity prices. Besides, the investment made by larger companies in critical minerals significantly lags behind those made by junior companies. Additionally, the focus of exploration activity for critical minerals predominantly lies in the earlier stages of the exploration process. We expect these initial results to be used as a step forward to facilitate the discussion about exploration policies and, consequently, the reliability of the supply chain. [ABSTRACT FROM AUTHOR]

We consider single-machine scheduling with a non-renewable resource. In this setting, we are given a set of jobs, each characterized by a processing time, a weight, and a resource requirement. At fixed points in time, certain amounts of the resource are made available to be consumed by the jobs. The goal is to assign the jobs non-preemptively to time slots on the machine, so that each job has enough resource available at the start of its processing. The objective that we consider is the minimization of the sum of weighted completion times. The main contribution of the paper is a PTAS for the case of 0 processing times ( 1 | r m = 1 , p j = 0 | ∑ w j C j ). In addition, we show strong NP-hardness of the case of unit resource requirements and weights ( 1 | r m = 1 , a j = 1 | ∑ C j ), thus answering an open question of Györgyi and Kis. We also prove that the schedule corresponding to the Shortest Processing Time First ordering provides a 3/2-approximation for the latter problem. Finally, we investigate a variant of the problem where processing times are 0 and the resource arrival times are unknown. We present a (4 + ϵ) -approximation algorithm, together with a (4 - ε) -inapproximability result, for any ε > 0 . [ABSTRACT FROM AUTHOR]

In our scientific approach, we aimed to emphasize the significance of sustainability in the research-development-innovation (RDI) activity. This activity should align with other economic activities and prioritize the utilization of renewable resources whenever feasible. In cases where renewable resources are not available, the use of non-renewable resources should be extended over a longer timeframe, allowing for the identification and exploration of renewable alternatives. The transfer of scientific knowledge (TSK) was also addressed, which should lead to an implementation of the results of scientific research in the economy, and the ratification of this transfer can be done both through qualitative and quantitative measures, with a greater emphasis on qualitative measures. This transfer of knowledge must constantly adapt, especially when there are external factors, such as the COVID-19 pandemic and the war in Ukraine in recent years.

The objective of this study is to assess the short and long run effects of renewable and non-renewable resource rents on economic growth in Cameroon. Taking crude oil rents and forest resource rents as proxies for non-renewable and renewable resources respectively for the period 1977–2018, we employed the autoregressive and dynamic autoregressive distributive lag (ARDL/DynARDL) modelling frameworks to achieve the stated objective. Results from the ARDL model indicate that, in the short run, both the renewable and non-renewable resources have a positive and significant effect on economic growth but the point resource is more significant than the diffused. A clear disparity in results is however noticed in the long run. While the point resources show that natural resources are a curse to long run growth, the diffuse resources reveal that natural resources are a blessing to long run growth. From the DynARDL simulation, a negative shock of the point resources leads to a fall in economic growth whereas diffuse resource indicates an increase. This shows that point resources are more prone to the resource-curse thesis and diffuse resources to resource-bless thesis. Contingent on these findings, the Cameroon government should ensure a proper allocation of natural resource revenues especially point resource rents to growth-inducing investment or social overhead capital such as open new markets, transport infrastructures, and power sectors, so as to enhance growth and development.

The NP-hard problem Material Consumption Scheduling and related problems have been thoroughly studied since the 1980's. Roughly speaking, the problem deals with scheduling jobs that consume non-renewable resources—each job has individual resource demands. The goal is to minimize the makespan. We focus on the single-machine case without preemption: from time to time, the resources of the machine are (partially) replenished, thus allowing for meeting a necessary precondition for processing further jobs. We initiate a systematic exploration of the parameterized computational complexity landscape of Material Consumption Scheduling, providing parameterized tractability as well as intractability results. Doing so, we mainly investigate how parameters related to the resource supplies influence the problem's computational complexity. This leads to a deepened understanding of this fundamental scheduling problem. [ABSTRACT FROM AUTHOR]

Throughout a long historical period, the natural resources of the world have been managed by different human communities. Living within the boundaries of their own ecosystems forces people to develop a deep knowledge of managing their natural resources. Whether they and their children will survive directly depends on their behavior. People have given the land and natural resources a social and symbolic value that goes beyond their immediate use value. This symbolism is based on ecological principles and supports a system of ethical, social and economic rules that are adaptive. This means that these principles and rules help human communities prevent the overexploitation of natural resources, preserve their connections with the surrounding ecosystems, so that people can live within the limits imposed by the availability of resources and technology. Over the course of the last few generations, however, the world's diversity of cultures, along with their adaptations to local environmental conditions, has been rapidly disintegrating under the influence of a new, global culture characterized by extremely high levels of consumption. Economic growth based on fossil fuel energy led to the rapid development of industry and international trade, and improved lifestyles as well as advances in health care led to rapid growth in human population and consumption. As a consequence, the search for new ways of extracting resources, involving powerful machines and efficient technologies, which absorb the traditions of conservation of nature built by local human communities during their long historical experience of survival, is intensified. Mechanisms developed as adaptations to the environment over hundreds of years are rapidly breaking down as a result of globalization, thereby freeing humans from their traditional environmental constraints. [ABSTRACT FROM AUTHOR]

Energy is an important resource for human society and plays an important role in the development of society. However, due to the growing demand for energy in many countries around the world, the consumption of traditional fossil fuels such as coal is accelerating lead to problems such as resource scarcity, environmental pollution, and energy crisis are becoming increasingly prominent, which greatly restricts the sustainable development of the economy and human society, especially in areas where the utilization rate of new and renewable energy is not high. In order to realize environmental design and reduce pollution and solve problems such as resource shortages, this paper studies the utilization of new energy based on environmental design and realization. The experimental results show that the research on new energy based on environmental design and implementation can improve the utilization efficiency of new energy by 5.31%. This eases the future energy crisis and enables new energy to gradually replace solid resources such as fossil fuels as the main energy consumption. It can also solve the problem of energy shortage, reduce the waste and pollution of old energy in the environment, and improve the protection of the environment.

The green paradox describes an undesirable and socially inefficient phenomenon caused by the expansionary reactions of the supply as a response to the various mechanisms that combat climate change. This article seeks to understand and aggregate the different drivers of this phenomenon portrayed in the literature, as well the empirical evidence associated and the proposed solutions. For this purpose, compilation and systematization of the various scientific contributions up to date in this context have been elaborated and the driver's effective impact on the European scenario was evaluated, using a balanced panel for 28 countries in Europe over 1996–2018 and the generalized method of moments (GMM) econometric procedure. Proxies for all provocateurs identified in the state of the art were incorporated in this study: (i) environmental taxes, (ii) green support, (iii) uncertain property rights, (iv) emissions limit (cap), and (v) temporal lag. The dependent variables used are (1) the ratio between the annual production/extraction of oil and the consumption of primary energy and (2) the carbon dioxide (CO2) intensity. We have obtained evidences that the hiatus in the implementation of the European emission cap mechanism has generated a strong green paradox. Moreover, a robust reflection regarding the economic and environmental adequacy of green supports should be considered due to its questionable net benefits. Lastly, we offer some recommendations of public environmental policies that escape the paradoxical phenomenon, through the enunciation of the conditionalities of these provocateurs. [ABSTRACT FROM AUTHOR]

In our scientific approach, we aimed to emphasize the significance of sustainability in the research-development-innovation (RDI) activity. This activity should align with other economic activities and prioritize the utilization of renewable resources whenever feasible. In cases where renewable resources are not available, the use of non-renewable resources should be extended over a longer timeframe, allowing for the identification and exploration of renewable alternatives. The transfer of scientific knowledge (TSK) was also addressed, which should lead to an implementation of the results of scientific research in the economy, and the ratification of this transfer can be done both through qualitative and quantitative measures, with a greater emphasis on qualitative measures. This transfer of knowledge must constantly adapt, especially when there are external factors, such as the COVID-19 pandemic and the war in Ukraine in recent years. [ABSTRACT FROM AUTHOR]

Global mine production of copper has risen more than 80 times over the last 135 years. What were the main drivers? I examine this question based on copper market data from 1880 to 2020. I employ a structural time series model with sign restrictions to identify demand and supply shocks. I find that a deterministic trend drives most of the output growth. At the same time, unpredictable demand and supply shocks caused substantial fluctuations around the trend. A global commodity demand shock that is, for example, linked to a 3% unexpected expansion of the global economy due to rapid industrialization causes a 10% rise in the real copper price, incentivizing a 5% increase in global copper production. This provides empirical evidence for the feedback control cycle of mineral supply. [ABSTRACT FROM AUTHOR]

Based on the goal of maximizing input and output of resources development department and final product supply department, a regularized decision is made for the development of non-renewable resources. The Lagrange relaxation algorithm based on asynchronous subgradient method is used to solve the growth rate of price and output of non-renewable resources under steady state, and the numerical simulation and sensitivity analysis are carried out.Technological innovation plays a decisive role in the regularization development of non-renewable resources. The constraints of resource development priority, production constraints and net present value of production in the final product supply department and resource development department will significantly affect the growth rate of non-renewable resources output. Accordingly, a management strategy for developing regularization and rational allocation of non-renewable resources is put forward. [ABSTRACT FROM AUTHOR]

The study sought to test the applicability of Hotelling's rule to gold extraction in South Africa. In environmental economics, Hotelling's rule has come to be a pillar of the exhaustible resources framework and in addition to this, it has presented essential insights into the consumption and extraction of non-renewable resources. According to Hotelling's Rule, the extraction path in competitive market economies will, under certain circumstances, be socially optimal. An extraction path that is not socially optimal compromises the welfare of future generations. The welfare of South Africa's present population, particularly in the future, will be greatly determined by the stock of natural resources available. Currently, the production processes deplete natural resources in a way that is not sustainable. For instance, South Africa's gold reserves are becoming depleted at a rate that, within 25 to 33 years, will mean the end of the industry on which South Africa's economy has been built. This raises questions regarding how much of these non-renewable resources (gold) should be extracted today, and how much should be saved for future use or for future generations. Is gold being depleted more rapidly than the optimisation level suggested by Hotelling's Rule? In order to empirically test Hotelling's Rule, the study was guided by previous literature that had sought to test it, namely, the previously used graphical analysis and autoregressive distributed lag (ARDL) approach to assess the applicability of Hotelling's Rule. The results showed that there seems to be no significant relationship between interest rates and gold processes. This shows that Hotelling's Rule does not hold in South Africa. The results of the study suggested that the gold extraction in South Africa is not following a social optimal path. The study recommended that the government come up with measures that prolong the lifespan of the gold reserves. These included research and development to promote technological innovations in the mining sector. [ABSTRACT FROM AUTHOR]

We consider single machine scheduling problems with additional non-renewable resource constraints. Examples for non-renewable resources include raw materials, energy, or money. Usually they have an initial stock and replenishments arrive over time at a-priori known time points and quantities. The jobs have some requirements from the resources and a job can only be started if the available quantity from each of the required resources exceeds the requirements of the job. Upon starting a job, it consumes its requirements which decreases the available quantities of the respective non-renewable resources. There is a broad background for this class of problems. Most of the literature concentrate on the makespan, and the maximum lateness objectives. This paper focuses on the total weighted completion time objective for which the list of the approximation algorithms is very short. We extend that list by considering new special cases and obtain new complexity results and approximation algorithms. [ABSTRACT FROM AUTHOR]

Sustainable Development implies slowing the rate of utilization and eventual depletion of non-renewable resources such as oil and metals. Non-renewable resources are now commonly traded, often as derivatives, through electronic trading exchanges and studies the impact of that trading on sustainable development are underrepresented. Commodity-currency research since 2003 to some extent has focused on the relationship between commodity prices – including non-renewable resources – and the exchange rates of the currencies of the nations that are extracting those commodities. To a lesser extent, other research on non-renewable resource development has focused on technology and innovation. Here we address one issue at the core of non-renewable sustainable development: the question of commodity-currency linkages and spillovers and their effects on price stability. Our research tool is an economic interpretation of the Lotka-Volterra equations. Using Lotka-Volterra parameters from the fit to actual CAD XCT data, we find that carrying out the currency-commodity dynamics over several centuries demonstrates the possibility for cyclical unsustainable hyperinflation. Devaluing or inflating the currencies or commodities is not a solution to hyperinflation. The solution to hyperinflation is to increase β (the effect of the commodity on the currency) and/or δ (the price decrease rate of the commodity when the currency is absent) and/or decrease γ (the inflation rate of the commodity in the presence of the currency).

The purpose of this study is to investigate how the long‐run growth rate of per capita output is determined when an economy is subject to non‐renewable resource constraints and the population growth is negative by using a theoretical model. From this, we can examine the effect of population decline and the effect of depletion of natural resources on economic growth. Our results show that irrespective of whether the population growth rate is positive or negative, the long‐run growth rate of per capita output can be positive depending on conditions. This result suggests that even an economy with non‐renewable resources and declining population can obtain sustainable economic growth. [ABSTRACT FROM AUTHOR]

In this paper, we investigate an open problem by Györgyi and Kis for a single-machine scheduling problem with a non-renewable resource (NR-SSP) and total weighted completion time criterion. The problem is NP-hard, even if every job has the same processing time, and each weight is equal to its required amount of the resource. Györgyi and Kis prove that a simple list scheduling algorithm for this special case is a 3-approximation algorithm and conjecture that the algorithm for the case is a 2-approximation algorithm. We prove their conjecture. More strongly, we show that the approximation ratio is strictly less than 2 for any instance, and for any ϵ > 0 , there exists an instance for which the approximation ratio is more than 2 - ϵ . [ABSTRACT FROM AUTHOR]

This paper empirically analyzes the existence of market power in the global iron ore market during the period from 1993 to 2012. Using an innovative stochastic frontier analysis approach, we investigate the relationship between individual firm characteristics, macroeconomic conditions and the individual ability of firms to generate markups in the global iron ore market. Our findings indicate that the markups on average amount to 20%. Moreover, location of the main production site and experience measured in years of production are identified to be the most important determinants of the magnitude of firm-specific markups. [ABSTRACT FROM AUTHOR]

Carbon capture and storage in salt domes or in inactive fields is seen as an appealing option to meet the ambitious objectives of the Paris Agreement. Captured CO 2 emissions can also be injected in active fields to enhance gas or oil recovery. We examine the optimal scale and timing of these different capturing and storage options in a dynamic model of an economy subject to a carbon budget. We consider the socially optimal outcome as well as the outcome under laissez-faire. The social optimum can have different forms depending on the initial carbon budget, the fossil fuel resource stock and the stock of already injected CO 2 in active fields. The level and convexity of the costs of capturing, storing and producing renewable energy plays a role as well. We specify the conditions under which each possible sequence of regimes – no capturing, only enhanced recovery, only storage without enhanced recovery, a combination of both or only renewables – occurs. We quantify our analytical results by calibrating the model and running simulations. [ABSTRACT FROM AUTHOR]

The possibility of non-constant discounting is important in environmental and resource management problems where current decisions affect welfare in the far-distant future, as with climate change. The difficulty of analyzing models with non-constant discounting limits their application. We describe and provide software to implement an algorithm to numerically obtain a Markov Perfect Equilibrium for an optimal control problem with non-constant discounting. The software is available online. We illustrate the approach by studying welfare and observational equivalence for a particular renewable resource management problem.

This paper considers the complementarity and substitutability of natural resources and physical capital. Unlike existing empirical research, concentrated on the estimation of the elasticity of substitution between energy and capital, the author focuses on macro data and the growth theory approach. The author considers the standard economic long-run growth models with substitutability or complementarity among natural resource use and physical capital in the production process. He derives from these models empirically verifiable theoretical relationships between their rates of growth. The author also uses cross-country long-run data to obtain an empirical correlation between these growth rates and finds evidence in favour of gross complementarity between the examined factors of production on the macro level in the long run. [ABSTRACT FROM AUTHOR]

In this paper, we describe new complexity results and approximation algorithms for single-machine scheduling problems with non-renewable resource constraints and the total weighted completion time objective. This problem is hardly studied in the literature. Beyond some complexity results, only a fully polynomial-time approximation scheme (FPTAS) is known for a special case. In this paper, we discuss some polynomially solvable special cases and also show that under very strong assumptions, such as the processing time, the resource consumption and the weight is the same for each job; minimizing the total weighted completion time is still NP-hard. In addition, we also propose a 2-approximation algorithm for this variant and a polynomial-time approximation scheme (PTAS) for the case when the processing time equals the weight for each job, while the resource consumptions are arbitrary. [ABSTRACT FROM AUTHOR]

We study the transition to a carbon-free economy in a model with a polluting non-renewable resource and a clean renewable resource. Transforming primary energy into ready-to-use energy services is costly and more efficient energy transformation rates are more costly to achieve. Renewable energy competes with food production for land and the food productivity of land can be improved at some cost. To avoid catastrophic climate damages, the pollution stock is mandated to stay below a given cap. When the economy is not constrained by the cap, the efficiency of energy transformation increases steadily until the transition toward the ultimate green economy; when renewable energy is exploited, its land use rises at the expense of food production; food productivity increases together with the land rent but food production drops; the food and energy prices increase and renewables substitute for non-renewable energy. During the constrained phase, the economy follows a constant path of prices, quantities, efficiency rates, food productivity and land rent, a phenomenon we call the 'ceiling efficiency paradox'. [ABSTRACT FROM AUTHOR]

This paper explores whether climate policy justifies developing more shale gas and addresses the question of a potential arbitrage between shale gas development and the transition to clean energy. We construct a Hotelling-like model where electricity may be produced by three perfectly substitutable sources: an abundant dirty resource (coal), a non-renewable less polluting resource (shale gas), and an abundant clean resource (solar). The resources differ by their carbon contents and their unit costs. Shale gas extraction's technology (fracking) generates local damages. Fixed costs must be paid to develop shale gas and to deploy the clean resource on a large scale. Climate policy takes the form of a carbon budget. We show that, at the optimum, a more stringent climate policy does not always go together with an increase of the quantity of shale gas extracted, and that banning shale gas extraction most often leads to bring forward the development of the clean resource, but not always. We calibrate the model for Europe in order to determine whether shale gas should be extracted and in which amount, and to evaluate the effects of a moratorium on shale gas use. [ABSTRACT FROM AUTHOR]

Most environmental damage can be reduced through investments in the management of the pollutants that cause this damage. In the case of climate change, for instance, the harmful effects of the accumulated stock of greenhouse gases depend on the adaptation effort. Our aim is to analyze which economic policy schemes can restore the social optimum in such contexts. We consider a simple endogenous growth model with a polluting non-renewable resource and directed technical change, in which the environmental damage (and unique externality) depends on the accumulated stock of pollutant as well as on a stock of green knowledge dedicated to its management. Here, the socially optimal policy consists in a tax on the environmental damage, which provides the right incentives to (a) invest in green knowledge and (b) mitigate pollutant flows. More usual—and more easily implementable—environmental policies like taxes on pollution flows (e.g., carbon tax) cannot yield first-best outcomes in this context since they do not provide the right incentives to invest in the management of the emitted pollutants. We nevertheless show how coupling such a type of policy tool with a subsidy to green R&D can restore the social optimum. [ABSTRACT FROM AUTHOR]

The concept of sustainable development, resulted from the reconsideration of the report between development and pollution in the light of the interdependencies among the components of development, defines the profound change in which the exploitation of resources, direction of investments, the development of technologies takes a new path in the sense that, by their judicious harmonization, provides significant increase of the present and future potential to meet the requirements of society. Such a development is based on economic growth, which is, in fact, its spring, but also on new concepts and values that provide a superior framework of transposing the growth coordinates. Such a framework should provide incentives to accelerate economic growth, whose objectives, ways and tools are defined in a long-term perspective, able to provide large openings to the real progress of society at all levels and provide solutions for the effective and continuous support for this progress. Therefore, in this article, we identify and explain the three dimensions of sustainable development: economic, social and environmental.

The extractive industry is unanimously acknowledged as being a vital sector of any country which owns workable natural resources. The experts claim that this industry is a source of foreign income, of direct foreign investments and it is also the main and sometimes the only energy provider of a country. The activities carried out within the extractive industry of any country provide employment to population and contribute to the public budget by taxes and dues, while the incomes resulted from these activities can be directed towards charity; however, at the same time, there is a certain environmental risk related to each initiative that is being carried out in this industry.

This paper considers the distributional impact of optimal carbon taxation on fossil-fuel owners. A carbon-emitting exhaustible resource competes with a dirtier abundant resource and a clean backstop. A time-dependent carbon tax is set to optimally use these resources under a cap constraint over CO 2 atmospheric concentration. As the cap is tightened, the dirtier resource becomes less competitive compared to the exhaustible resource (the “competition effect”), but the timing and duration of extraction of the exhaustible resource is modified (the “timing effect”). We provide analytical expressions of these effects, and determine conditions over size of reserves, pollution contents, extraction costs and demand elasticity such that the exhaustible-resource owners’ profits increase as the ceiling is tightened. Calibrations for the transport and power sectors suggest that the profits of conventional-oil and natural-gas owners increase compared to a baseline without regulation for plausible carbon-ceiling values. [ABSTRACT FROM AUTHOR]

Non-renewable resources include a large variety of deposits that have been formed by geological processes over millions of years. Although extraction of such resources provides benefits as employment and economic revenues, it also contributes to negative environmental externalities and it increases resource scarcity. An important policy question is how to optimally extract non-renewable resource stocks over time while taking possible substitutes and recycling into account. The present paper adds to the literature by developing a generic numerical optimisation model that can be used to simulate non-renewable resource management regimes and the effects of different policy instruments deployed at different stages of the resource’s life cycle. By including recycling and substitution, the model extends the seminal cake-eating Hotelling model that dominates the non-renewable resource economics literature. In addition to being generically designed, the model can accommodate for non-competitive market settings, interacting policy instruments and environmental externalities at different stages of the material’s life cycle. The model’s possibilities are illustrated by means of a numerical simulation example for the extraction of sand. [ABSTRACT FROM AUTHOR]

Water footprint is an indicator of freshwater use that looks not only at direct water use of a consumer or producer, but also at indirect water use; it can be regarded as a comprehensive indicator of freshwater resources appropriation, next to the traditional and restricted measure of water withdrawal. It could be counted in terms of the sum of direct and indirect water costs in all processes and input-output analysis to detailed water used in all plant. In this paper, the application of the water footprint in a construction business located in Eastern Sicily is presented, its main activity is represented by the production of aggregates, bituminous and concrete mixes. In order to identify the economic, social and environmental advantages, we quantify this multi-dimensional indicator and we analyse the water incorporation into products, evaporation, abstracted from ground-or surface water and returned to another catchments or sea, with unavailable degradation in quality. It consists of two main components: the operational (or direct) water footprint of a business is the volume of freshwater consumed or polluted due to the business's own operations. Thanks to the calculation of the Water Footprint the amount of water resources that a company of this size really requires was understood and greatly exploits the opportunity and the strategies to reduce its water consumption, such as installation of a system for collecting rainwater, continuous recycling system and new sleeve filters. The costs of these investments were calculated by choosing different alternatives to safe non-renewable water. [ABSTRACT FROM AUTHOR]

The article addresses the complexities of modelling and forecasting of non-renewable resources production (oil, gas, coal, etc.), by means of combining five production trend models with “custom” asymmetry, as well as with six models of fluctuation components: harmonic, independent from the trend; harmonic, proportional to the trend; simultaneous presence of the first and second models of fluctuation components; harmonic with “weighted amplitude”; “frequency-weighted” harmonics. The purpose of this research is to increase the production forecasting accuracy, by considering the fluctuation components models and by monitoring the models' evolution and fluctuation. The offered methods provide a production forecasting accuracy increase for oil in the U.S. - by 3.2%, for coal in Germany - by 5%, and gas in the Volgograd region (Russia) - by 25%. [ABSTRACT FROM AUTHOR]

In the presence of implementation lags, announced Pigouvian taxation leads to fossil fuel prices that are too low from society's perspective. This results in excessive emissions and reduced incentives for green innovation. Such effects are compounded by the presence of pre-existing subsidies to fossil fuel use. We show that the intertemporal resource tax path may need to be modified to optimally take into account the perverse incentives from policy lags and pre-existing policies. We find that it might be optimal to subsidize, rather than tax resource extraction at the instant of implementation. [ABSTRACT FROM AUTHOR]