Comprehensive evidence implies a higher social cost of CO2.

The social cost of carbon dioxide (SC-CO2) measures the monetized value of the damages to society caused by an incremental metric tonne of CO2 emissions and is a key metric informing climate policy. Used by governments and other decision-makers in benefit-cost analysis for over a decade, SC-CO2 estimates draw on climate science, economics, demography and other disciplines. However, a 2017 report by the US National Academies of Sciences, Engineering, and Medicine1 (NASEM) highlighted that current SC-CO2 estimates no longer reflect the latest research. The report provided a series of recommendations for improving the scientific basis, transparency and uncertainty characterization of SC-CO2 estimates. Here we show that improved probabilistic socioeconomic projections, climate models, damage functions, and discounting methods that collectively reflect theoretically consistent valuation of risk, substantially increase estimates of the SC-CO2. Our preferred mean SC-CO2 estimate is $185 per tonne of CO2 ($44-$413 per tCO2: 5%-95% range, 2020 US dollars) at a near-term risk-free discount rate of 2%, a value 3.6 times higher than the US government's current value of $51 per tCO2. Our estimates incorporate updated scientific understanding throughout all components of SC-CO2 estimation in the new open-source Greenhouse Gas Impact Value Estimator (GIVE) model, in a manner fully responsive to the near-term NASEM recommendations. Our higher SC-CO2 values, compared with estimates currently used in policy evaluation, substantially increase the estimated benefits of greenhouse gas mitigation and thereby increase the expected net benefits of more stringent climate policies.

Health benefits of decreases in on-road transportation emissions in the United States from 2008 to 2017.

Decades of air pollution regulation have yielded enormous benefits in the United States, but vehicle emissions remain a climate and public health issue. Studies have quantified the vehicle-related fine particulate matter (PM2.5)-attributable mortality but lack the combination of proper counterfactual scenarios, latest epidemiological evidence, and detailed spatial resolution; all needed to assess the benefits of recent emission reductions. We use this combination to assess PM2.5-attributable health benefits and also assess the climate benefits of on-road emission reductions between 2008 and 2017. We estimate total benefits of $270 (190 to 480) billion in 2017. Vehicle-related PM2.5-attributable deaths decreased from 27,700 in 2008 to 19,800 in 2017; however, had per-mile emission factors remained at 2008 levels, 48,200 deaths would have occurred in 2017. The 74% increase from 27,700 to 48,200 PM2.5-attributable deaths with the same emission factors is due to lower baseline PM2.5 concentrations (+26%), more vehicle miles and fleet composition changes (+22%), higher baseline mortality (+13%), and interactions among these (+12%). Climate benefits were small (3 to 19% of the total). The percent reductions in emissions and PM2.5-attributable deaths were similar despite an opportunity to achieve disproportionately large health benefits by reducing high-impact emissions of passenger light-duty vehicles in urban areas. Increasingly large vehicles and an aging population, increasing mortality, suggest large health benefits in urban areas require more stringent policies. Local policies can be effective because high-impact primary PM2.5 and NH3 emissions disperse little outside metropolitan areas. Complementary national-level policies for NOx are merited because of its substantial impacts-with little spatial variability-and dispersion across states and metropolitan areas.

Greenhouse Gas Emission Efficiencies of World Countries.

Greenhouse gas emissions have increased rapidly since the industrial revolution. This has led to an unnatural increase in the global surface temperature, and to other changes in our environment. Acknowledging this observation, the United Nations Framework Convention on Climate Change started an international environmental treaty. This treaty was extended by Kyoto protocol, which was adopted on 11 December 1997. Using the stochastic frontier analysis, we analyze the efficiencies of countries in terms of achieving the lowest greenhouse gas emission levels per GDP output in the years between 1990-2015. We find that the average greenhouse gas emission efficiencies of world countries for the time periods 1990-1997, 1998-2007, 2008-2012, and 2013-2015 are 82.40%, 90.37%, 89.54%, and 84.81%, respectively. Moreover, compared to the 1990-1997 period, 92.50%, 79.51%, and 59.84% of the countries improved their greenhouse gas emission efficiencies in the 1998-2007, 2008-2012, and 2013-2015 periods, respectively. Hence, the Kyoto protocol helped in increasing greenhouse emission efficiency. However, this efficiency-boosting effect faded away over time.

The tail dependence of the carbon markets: The implication of portfolio management.

Emission trading scheme (ETS), the most popular market-based instrument, is widely used to solve carbon emission problems in the world. With the development of carbon market, carbon asset has been a popular financial product to invest and the risk management becomes important for government, regulated enterprises and other investors. As carbon prices have tail characteristics, this paper explores the extremal risks between carbon markets in US, Europe and China using tail dependence correlation coefficients. The empirical analysis demonstrates the tail dependence structure between carbon markets in US. and Europe is the same sign, which indicates that it is unwise to hold these two carbon assets as a portfolio. Moreover, the co-movements between European Union Emission Trade Scheme (EU ETS) and China's carbon markets are partly significant, and the operation mechanisms in China should be improved. In addition, the tail dependence test among the carbon pilots in China shows diversity. Hubei carbon trading pilot, located in central China, has extremal dependence with all other selected pilots for its regulatory program operation. The findings give insight to the carbon market regulars to improve the operation mechanism and are also useful for the investors to manage their portfolios, policymakers to make practically applicable regulations, and relevant organizations to develop procedures.

Financial Leverage, Economic Growth and Environmental Degradation: Evidence from 30 Provinces in China.

This study seeks to investigate the endogenous relationship between financial leverage, economic growth and environmental degradation in China by employing a the generalized moments method (GMM) panel vector autoregressive (PVAR) approach with a panel of data from China's 30 provinces over the period 1997-2016. Three key results arise. First, financial leverage can significantly lessen economic growth, while economic growth decreases financial leverage. Second, economic growth provides an important impetus to boost carbon emissions. Finally, carbon emissions have inversely pushed up financial leverage. These results reflect to some extent China's impressive rate of economic growth, which has been attained via continuously supporting inefficient state-owned enterprises and heavy and polluting industries through bank loans. The results are further supported by the variance decomposition. The findings provide valuable policy implications for deepening financial supply-side structure reform to transform and upgrade China's real economy. These policy implications are conductive to developing a low-carbon economy.

Transparency of Financial Reporting on Greenhouse Gas Emission Allowances: The Influence of Regulation.

This study focuses on the transparency of financial reporting on emission allowances (EA) and greenhouse gas (GHG) emissions within the European Union Emissions Trading Scheme (EU ETS). In particular, the different accounting treatments adopted by standard setters and professionals were analyzed to evaluate the influence of regulation in the transparency of financial reporting on EA and GHG emissions. Based on a sample of 85 companies registered with the Portuguese, Spanish, and French National Plans of Allocation (NPAs), data collected from the annual reports were analyzed for the 2008-2014 period. The results were obtained based on descriptive, logistic regressions and panel data statistical techniques, and they show that better levels of transparency of financial reporting on EA and GHG emissions are conditioned by a variety of accounting policies, which compromises the comparability of the financial information. The adoption of the International Accounting Standards Board (IASB) standards set lead to a greater dispersion in the choice of the accounting approach and a higher probability of not disclosing any information, as well as adopting off-balance sheet policies. Therefore, the regulatory factor is a determinant of the level of transparency of financial reporting on EA and GHG emissions, contributing to reduce strategies of omission.

Addressing climate change through a market mechanism: a comparative study of the pilot emission trading schemes in China.

The questions of how to mitigate climate change and its impact on human health are currently high on the Chinese agenda for future development. The emission trading scheme (ETS) has become one of China's most important instruments to address climate change through a market mechanism. In the wake of the evolution from regional pilots to a nationwide scheme, it is inevitable to be confronted with tremendous political-economic-institutional challenges. To facilitate a smooth start-up of the upcoming nationwide ETS, this study provides a systematic overview of seven ETS pilots, involving the detailed comparison of ETS design and the in-depth evaluation of market performance, both internal and external performance, based on trading data. Then, the achievements and deficiencies of seven ETS pilots are summarized, several challenges for the current time are discussed, and policy proposals for China's national-level ETS are navigated further coupled with international experience. This study finds that China's ETS pilots, from the short-term perspective, are successful, especially in the reinforcement of China's capacity to develop a market-based scheme in an economy that still cherishes many non-market endowments. However, deficiencies lie in both the internal and external market performance, such as the carbon price lacking a signal function, insufficient incentives for compliance, too low market liquidity, and much too high market fragmentation. Moreover, the retrospective examination of China's ETS pilots suggests that a nationwide ETS should at least be based on an extension of the cap duration from single year to several years, uniform rules on monitoring/reporting/verification and allowance allocation, and the improvement of institutional foundation.

A comparative analysis of Chinese regional climate regulation policy: ETS as an example.

An effective and powerful regulation is indispensable for the development and smooth operation of a cap-and-trade emission trading scheme (ETS). Seven regional pilot ETSs have been established and gradually improved in China, from which the experiences and lessons learned may provide useful references to facilitate China's national ETS regulation. This article systematically reviews and compares the practices and policies of carbon trading regulation in China's seven pilot schemes from three major aspects of regulatory institutions and subjects, regulatory objects and content, and regulatory means and techniques, and covering both internal and external regulatory architectures. The comparative analysis has demonstrated that the regional pilot schemes have made notable achievements in developing ETS regulatory systems with Chinese characteristics, but they still have considerable deficiencies. Referencing both international and domestic pilot experiences, this study recommends that China's national ETS improve regulatory institutional basis, foster an extensive participation of pluralistic regulatory subjects with a clear division of powers and responsibilities, establish effective regulatory systems on carbon finance, and continuously enrich regulatory techniques and platforms.

Costs of switching to low global warming potential inhalers. An economic and carbon footprint analysis of NHS prescription data in England.

OBJECTIVES: Metered-dose inhalers (MDIs) contain propellants which are potent greenhouse gases. Many agencies propose a switch to alternative, low global warming potential (GWP) inhalers, such as dry powder inhalers (DPIs). We aimed to analyse the impact on greenhouse gas emissions and drug costs of making this switch. SETTING: We studied National Health Service prescription data from England in 2017 and collated carbon footprint data on inhalers commonly used in England. DESIGN: Inhalers were separated into different categories according to their mechanisms of action (eg, short-acting beta-agonist). Within each category we identified low and high GWP inhalers and calculated the cost and carbon impact of changing to low GWP inhalers. We modelled scenarios for swapping proportionally according to the current market share of each equivalent DPI (model 1) and switching to the lowest cost pharmaceutically equivalent DPI (model 2). We also reviewed available data on the carbon footprint of inhalers from scientific publications, independently certified reports and patents to provide more accurate carbon footprint information on different types of inhalers. RESULTS: If MDIs using HFA propellant are replaced with the cheapest equivalent DPI, then for every 10% of MDIs changed to DPIs, drug costs decrease by £8.2M annually. However if the brands of DPIs stay the same as 2017 prescribing patterns, for every 10% of MDIs changed to DPIs, drug costs increase by £12.7M annually. Most potential savings are due to less expensive long-acting beta-agonist (LABA)/inhaled corticosteroids (ICS) inhalers. Some reliever inhalers (eg, Ventolin) have a carbon footprint over 25 kg CO2e per inhaler, while others use far less 1,1,1,2-tetrafluoroethane (HFA134a) (eg, Salamol) with a carbon footprint of <10 kg CO2e per inhaler. 1,1,1,2,3,3,3-Heptafluoropropane (HFA227ea) LABA/ICS inhalers (eg, Flutiform) have a carbon footprint over 36 kg CO2e, compared with an equivalent HFA134a combination inhaler (eg, Fostair) at <20 kg CO2e. For every 10% of MDIs changed to DPIs, 58 kt CO2e could be saved annually in England. CONCLUSIONS: Switching to DPIs would result in large carbon savings and can be achieved alongside reduced drug costs by using less expensive brands. Substantial carbon savings can be made by using small volume HFA134a MDIs, in preference to large volume HFA134a MDIs, or those containing HFA227ea as a propellant.

Triangular nexus between foreign direct investment, international tourism, and energy consumption in the Chinese economy: accounting for environmental quality.

Recently, China is named among the most carbon dioxide (CO2)-emitting countries in the world after the United State of America (USA). A major part of Chinese carbon dioxide emissions is as a result of offshore industrial activities which come into the economy as foreign direct investment (FDI). Following this, the present study seeks to investigate the nexus between CO2 emissions, FDI, energy use, and tourism arrivals, and possibly to advise on who will bear the responsibility of offshore CO2 emissions. Utilizing ARDL-bound testing and Granger causality approaches for both short- and long-run effects the author found that economic growth (GDP) has a positive relationship with both tourism arrivals, energy use, FDI, and CO2.This contributes to heavy CO2 emissions which the author classified as the outsourced/offshore CO2emissions in China's FDI. Tourism arrivals have a bi-directional (feedback) causal relationship with energy use and a uni-directional causal relationship with CO2(transmitting from tourism to CO2). Both FDI and energy use have a bi-directional (feedback) causal relationship; CO2, energy use, and tourism arrivals have a unidirectional relationship with GDP which established the triangular nexus causality among the variables and the impact on GDP. Hence, the policy implication should be geared towards implementing the policies and regulations that will checkmate and reduce the excesses of foreign firms to the environment quality of China and promote environmentally friendly economic activities.

Turning the tide: The shift to climate change mitigation.

In the United States, a growing number of companies are taking progressive steps to reduce greenhouse gas (GHG) emissions. Already, more than half of all Fortune 100 companies have announced clean energy targets, signaling climate change risk reduction is becoming a top priority. Climate change is not without controversy, yet it is a real business concern among corporate executives and health care leaders alike. From fears stoked by devastating wildfires in California to a rising tide of financial hardships due to hurricane flooding in the Southeast, it seems no region is immune to Mother Nature's growing cost to business. This report addresses how health care leaders are approaching climate change initiatives across the country by examining research articles, key opinion leaders, and health care organizations on the bleeding edge of climate change reduction. In an already complex industry, health care leaders have a special responsibility to do no harm to the patients they serve and a financial responsibility to drive monetary returns for invested stakeholders. Significant cost savings, long-term risk reduction, and improved population health are a few of the benefits health care organizations around the country can gain from building a sound climate change mitigation strategy.

The causal nexus between energy consumption, carbon emissions and economic growth: New evidence from China, India and G7 countries using convergent cross mapping.

Understanding the causality between energy consumption, carbon emissions and economic growth is helpful for policymakers to formulate energy, environmental and economic policies. For the first time, based on nonlinear dynamics, this paper employs multispatial convergent cross mapping (CCM) to revisit the energy-carbon-economy causation for China, India and the G7 countries using both aggregate data and per capita data. The findings indicate that there are significant differences between developing countries and developed countries. A bidirectional nexus between energy consumption, carbon emissions and economic growth is found in China and India, but various causal relationships are identified in the G7 countries, including bidirectional, unidirectional and neutral nexus. The results confirm that the decoupling phenomenon is common in most G7 countries. By leveraging a variety of samples and a new approach, this study provides new evidence for policy authorities to formulate country-specific policies to obtain better environmental quality while achieving sustainable economic growth.

Estimation of marginal abatement costs of CO2 in Chinese provinces under 2020 carbon emission rights allocation: 2005-2020.

The calculation of marginal abatement costs of CO2 plays a vital role in meeting China's 2020 emission reduction targets by providing reference for determining carbon tax and carbon trading pricing. However, most existing researches only used one method to discuss regional and industrial marginal abatement costs, and almost no studies predicted future marginal abatement costs from the perspective of CO2 emission efficiency. To make up for the gaps, this paper first estimates marginal abatement costs of CO2 in three major industries of 30 provinces in China from 2005 to 2015 based on three assumptions. Second, based on the principle of fairness and efficiency, China's 2020 emission reduction targets are decomposed by province. Based on the ZSG-C-DDF model, the marginal abatement costs of CO2 in all provinces in China in 2020 are estimated and compared with the marginal abatement costs of 2005 to 2015. The results show that (1) from 2005 to 2015, marginal abatement costs of CO2 in all provinces show a fluctuating upward trend; (2) compared with the marginal abatement costs of primary industry or tertiary industry, most provinces have lower marginal abatement costs for secondary industry; and (3) the average marginal abatement costs of CO2 for China in 2020 are 2766.882 Yuan/tonne for the 40% carbon intensity reduction target and 3334.836 Yuan/tonne for the 45% target, showing that the higher the emission reduction target, the higher the marginal abatement costs of CO2. (4) Overall, the average marginal abatement costs of CO2 in China by 2020 are higher than those in 2005-2015. The empirical analysis in this paper can provide multiple references for environmental policy makers.

Decoupling emissions of greenhouse gas, urbanization, energy and income: analysis from the economy of China.

The adoption and ratification of relevant policies, particularly the household enrolment system metamorphosis in China, led to rising urbanization growth. As the leading developing economy, China has experienced a drastic and rapid increase in the rate of urbanization, energy use, economic growth and greenhouse gas (GHG) pollution for the past 30 years. The knowledge of the dynamic interrelationships among these trends has a plethora of implications ranging from demographic, energy, and environmental and sustainable development policies. This study analyzes the role of urbanization in decoupling GHG emissions, energy, and income in China while considering the critical contribution of energy use. As a contribution to the extant body of literature, the present research introduces a new phenomenon called "the environmental urbanization Kuznets curve" (EUKC), which shows that at the early stage of urbanization, the environment degrades however, after a threshold point the technique effects surface and environmental degradation reduces with rise in urbanization. Applying the autoregressive distributed lag model and the vector error correction model, the paper finds the presence of inverted U-shaped curve between urbanization and GHG emission of CO2, while the same hypothesis cannot be found between income and GHG emission of CO2. Energy use in all the models contributes to GHG emission of CO2. In decoupling greenhouse gas emissions, urbanization, energy, and income, articulated and well-implemented energy and urbanization policies should be considered.

The Impacts of Regulations and Financial Development on the Operations of Supply Chains with Greenhouse Gas Emissions.

To establish a micro foundation to understand the impacts of greenhouse gas (GHG) emission regulations and financial development levels on firms' GHG emissions, we build a two-stage dynamic game model to incorporate GHG emission regulations (in terms of an emission tax) and financial development (represented by the corresponding financing cost) into a two-echelon supply chain. With the subgame perfect equilibrium, we identify the conditions to determine whether an emission regulatory policy and/or financial development can affect GHG emissions in the supply chain. We also reveal the impacts of the strictness of GHG emission regulation, the financial development level, and the unit GHG emission rate on the operations of the supply chain and the corresponding profitability implications. Managerial insights are also discussed.

Pricing, Carbon Emission Reduction, Low-Carbon Promotion and Returning Decision in a Closed-Loop Supply Chain under Vertical and Horizontal Cooperation.

In this paper, we examine the influences of vertical and horizontal cooperation models on the optimal decisions and performance of a low-carbon closed-loop supply chain (CLSC) with a manufacturer and two retailers, and study optimal operation in the competitive pricing, competitive the low-carbon promotion, the carbon emission reduction, the used-products collection and the profits. We consider the completely decentralized model, M-R vertical cooperation model, R-R horizontal cooperation model, M-R-R vertical and horizontal cooperation model and completely centralized model, and also identify the optimal decision results and profits. It can be observed from a systematic comparison and numerical analysis that the completely centralized model is best in all optimal decision results among all models. In semi-cooperation, the M-R vertical cooperation model is positive, the R-R horizontal cooperation model is passive, and the positivity of the M-R-R vertical and horizontal cooperation model decreases with competitive intensity increasing in the used-products returning, carbon emissions reduction level, low-carbon promotion effort and the profits of the manufacturer and the entire supply chain.

Nutritional and greenhouse gas impacts of removing animals from US agriculture.

As a major contributor to agricultural greenhouse gas (GHG) emissions, it has been suggested that reducing animal agriculture or consumption of animal-derived foods may reduce GHGs and enhance food security. Because the total removal of animals provides the extreme boundary to potential mitigation options and requires the fewest assumptions to model, the yearly nutritional and GHG impacts of eliminating animals from US agriculture were quantified. Animal-derived foods currently provide energy (24% of total), protein (48%), essential fatty acids (23-100%), and essential amino acids (34-67%) available for human consumption in the United States. The US livestock industry employs 1.6 × 106 people and accounts for $31.8 billion in exports. Livestock recycle more than 43.2 × 109 kg of human-inedible food and fiber processing byproducts, converting them into human-edible food, pet food, industrial products, and 4 × 109 kg of N fertilizer. Although modeled plants-only agriculture produced 23% more food, it met fewer of the US population's requirements for essential nutrients. When nutritional adequacy was evaluated by using least-cost diets produced from foods available, more nutrient deficiencies, a greater excess of energy, and a need to consume a greater amount of food solids were encountered in plants-only diets. In the simulated system with no animals, estimated agricultural GHG decreased (28%), but did not fully counterbalance the animal contribution of GHG (49% in this model). This assessment suggests that removing animals from US agriculture would reduce agricultural GHG emissions, but would also create a food supply incapable of supporting the US population's nutritional requirements.

Integrating livestock health measures into marginal abatement cost curves.

Improving livestock health offers both private and social benefits. Among the potential social benefits is a reduction in the greenhouse gas (GHG) emissions arising from livestock production. Reductions in emissions intensity (the amount of GHG produced per kilogram of meat, milk or eggs) may occur, as improving health can lead to improvements in the parameters that emissions intensity is sensitive to, such as (for ruminants): maternal fertility and abortion rates, calf and lamb mortality rates and growth rates, milk yields and feed conversion rates. However, improved health is not yet widely recognised as a GHG mitigation measure due, in part, to difficulties in reliably quantifying the financial and GHG effects of disease control options. This paper discusses how the GHG effects of disease control can be quantified and included in a marginal abatement cost curve (MACC). To illustrate some of the challenges, it draws on the experience of including health measures in the most recent (2015) agricultural MACCs in the United Kingdom.

L'amélioration de la santé des animaux d'élevage apporte des bénéfices non seulement aux personnes et entreprises privées mais aussi à la société en général. La réduction des émissions de gaz à effet de serre est l'un des bénéfices potentiels apportés à la société par les élevages. Il est ainsi possible de réduire l'intensité des émissions (c'est-à-dire la quantité de gaz à effet de serre générée par kilogramme de viande, de lait ou d'oeufs), dans la mesure où l'amélioration de la santé animale s'accompagne d'une amélioration des paramètres qui influent sur l'intensité de ces émissions ; par exemple, chez les ruminants, le taux de fécondité, le taux d'avortements, le taux de mortalité néonatale et le taux de croissance chez les ovins et les caprins, la production de lait et le taux de conversion des aliments donnés aux animaux. Or, l'amélioration de la santé n'est pas toujours reconnue comme étant une mesure de réduction des gaz à effet de serre, en raison notamment de la difficulté de quantifier de manière fiable les effets des différentes stratégies zoosanitaires en termes financiers et d'émissions de gaz à effet de serre. Les auteurs proposent une méthode permettant de quantifier les effets des mesures de lutte contre les maladies animales sur les émissions de gaz à effet de serre et de les intégrer dans une courbe de coût marginal d'abattement. Afin d'illustrer certains enjeux en la matière, les auteurs présentent l'expérience conduite récemment (2015) au Royaume-Uni pour intégrer les mesures sanitaires dans les courbes de coût marginal d'abattement du secteur agricole.

El hecho de mejorar el estado de salud del ganado reporta beneficios de índole tanto privada como social. Entre los posibles beneficios sociales figura una reducción de las emisiones de gases de efecto invernadero resultantes de la producción pecuaria. Esas emisiones también pueden ser menos intensas (volumen de gases generados por kilogramo de carne, leche o huevos), pues la intensidad de las emisiones es sensible a una serie de parámetros cuyo valor mejora al hacerlo el estado de salud, tales como (en el caso de los rumiantes): tasas de fertilidad materna y de abortos; tasas de mortalidad y crecimiento en terneros y corderos; y tasas de producción de leche y de conversión alimenticia. Sin embargo, todavía no ha arraigado la idea de que la mejora del estado de salud es una medida de lucha contra los gases de efecto invernadero, debido en parte a las dificultades existentes para cuantificar con fiabilidad los efectos de los métodos de lucha zoosanitaria sobre parámetros económicos o sobre las emisiones. Los autores explican cómo cuantificar los efectos del control de enfermedades sobre los gases de efecto invernadero y a partir de ahí incluirlos en una curva del costo marginal de reducción. Para ilustrar algunos de los problemas que pueden surgir se refieren a la experiencia británica destinada a incluir parámetros que miden el estado de salud en las más recientes (2015) curvas del costo marginal de reducción en el ámbito agropecuario.