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The USA and China have the world's largest GDP and greenhouse gas emissions, as well as having a significant proportion of the world's total population. These form part of the triumvirate of influencing factors which potentially detrimentally impact upon sustainability. How the triumvirate factors have impacted upon the sustainability of the USA and China has not been adequately determined quantitatively or holistically. Understanding this can strongly indicate how significant levels of population, economic growth, and greenhouse gas emissions impacts and influences the indicated levels, nature, and dynamics of sustainability occurring. Therefore, to contribute towards developing understanding of the issues outlined, the Sustainability Dynamics Framework is applied to conduct a sustainability dynamic assessment for the USA and China 1995-2018. The results indicate both countries are consistently unsustainable due to significant levels of triumvirate-based factors, with differing dynamic trends, characteristics, and potential outcomes. The current static nature of the USA's environment-human system provides the opportunity for a managed co-evolutionary strategy. China's dynamic trends indicate a significant increasingly stressed environment-human system, which is at risk of a potential systemic crisis or collapse unless stringent corrective measures are implemented. In order for both countries to return to sustainability, there needs to be population mitigation to return them to optimum levels, and the use of contractionary policies and rapid decarbonation of their economies and societies. Unless this occurs, then their continued reticence to undertaking the urgent and necessary measures required not only risking their own future, but the world as well., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

US imports of wood and paper products from countries with emerging economies such as China and Brazil have dramatically increased in recent decades, partially displacing US domestic production. Such displacements may have reduced the direct production costs of these products, yet generated indirect economic and environmental impacts that are not well understood or taken into account. This study uses general equilibrium modeling to assess and compare the economy-wide impacts and greenhouse gas (GHG) consequences between US domestic production and imports from China and Brazil. Both the United States and China will benefit from enhancing US production of wood and paper products. In addition, strengthening the US wood products industries can help reduce GHG emissions and conserve tropical natural forests as China and Brazil import or use more tropical logs to produce wood products than the United States. These findings reveal the economic and environmental advantages of increasing US production of forest products, particularly wood products. [ABSTRACT FROM AUTHOR]

To achieve net-zero emissions by 2050, we need economic means of sequestering carbon dioxide (CO 2 ) and reducing greenhouse gas emissions (GHG). We analyze the sequestration potential of the Intermountain West (I-West) region, US, as a primary energy transition hub through analysis of wellbore retrofit potential and emission reduction in both fugitive gas abatement and flare gas. We selected the I-West region due to its abundant energy sources and oil and gas production legacy. Preliminary analysis hints that well retrofits can breathe new life into a well at a fraction of the cost of a new drill. With millions of potential candidates in the US, even a modest fraction (1% or less) suitable for retrofit could accelerate the shift to large-scale CO 2 sequestration. Fugitive gas, the unintentional release of wellbore gases such as methane, is a significant emissions source. Through conservative analysis, it is estimated that wellhead leakage alone may account for 5 million tonnes of carbon dioxide equivalent (CO 2 e) emissions. We conclude by assessing the CO 2 emissions from flaring, which is the burning of associated gas during well operations, conservative analysis indicates flaring contributes another 2 million tonnes of CO 2 emissions to the region. We find that with targeted retrofit and better controls on emissions sources, the I-West region can make a significant impact in the nation's push to become net-zero. This study outlines economic feasibility and actionable items to achieve the critical reductions in emissions and increases in sequestration necessary to attain net zero., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier Ltd.)

Global agricultural systems face one of the greatest sustainability challenges: meeting the growing demand for food without leaving a negative environmental footprint. United States (US) and China are the two largest economies and account for 39 % of total global greenhouse gases (GHG) emissions into the atmosphere. No-till is a promising land management option that allows agriculture to better adapt and mitigate climate change effects compared to traditional tillage. However, the efficacy of no-till for mitigating GHG is still debatable. In this meta-analysis, we comprehensively assess the impact of no-till (relative to traditional tillage) on GHG mitigation potential and crop productivity in different agroecological systems and management regimes in the US and China. Overall, no-till in China did not change crop yields, although soil CO 2 (8 %) and N 2 O (12 %) emissions decreased significantly, while soil CH 4 emissions increased by 12 %. In contrast to Chinese no-till, a significant improvement in crop yields (up to 12 %) was recorded on US cropland under no-till. Moreover, significant decreases in soil N 2 O (21 %) and CH 4 (12 %) emissions were observed. Of the three cropping systems, only wheat showed significant reduction in CO 2 , N 2 O and CH 4 emissions in the Chinese no-till system. In the case of US, no-till soybean-rice and maize cropping systems demonstrated significant emission reductions for N 2 O and CO 2 , respectively. Interestingly, yields of no-till maize in China and rice in US exceeded those of other no-till cereals. In China, no-till on medium-texture soils resulted in significant reductions in GHG emissions and higher crop yields compared to other soil types. In both countries, the relatively higher crop yields under irrigated versus non-irrigated no-till and the significant yield differences on fine textured soils under US no-till are likely due to the substantial N 2 O reductions. In summary, crop yield disparities from no-till between China and the US were related to the insignificant effects on controlling CH 4 emissions and successfully mitigating N 2 O, respectively. This study comprehensively demonstrates how cropping system and pedoclimatic conditions influence the relative effectiveness of no-till in both countries., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

The article reports on the proposal publishing companies to becoming entirely carbon neutral and reduce its carbon emission in the U.S. Hearst Corp. plans to consider the implications for their magazines after the calculation on the amount of carbon dioxide emissions produced in the process of publishing. On the other hand, Time Inc. announced that it had asked their paper suppliers to reduce their greenhouse gas emissions by 20 percent by 2012.

Edge-of-field management practices that reduce nutrient pollution from tile drainage while contributing habitat and other ecosystem services are needed to enhance agricultural systems in the US Corn Belt Region. In this review, we identified edge-of-field and catchment scale agricultural conservation practices for intercepting and treating tile drainage. The reviewed conservation practices were (1) controlled drainage, also known as drainage water management (USDA-NRCS Code 554); (2) drainage water recycling (USDA-NRCS Code 447); (3) denitrifying bioreactors (USDA-NRCS Code 605); (4) saturated buffers (USDA-NRCS Code 604); and (5) constructed or restored wetlands designed for water quality improvement (USDA-NRCS Code 656) herein referred to as water quality wetlands. We examined 119 studies that had information on one or more of the following ecosystem services: water retention, water quality improvement (e.g., nitrate, phosphate, sediment, or pesticide retention), wetland habitat (for birds, aquatic organisms, and pollinators), crop yield improvement, and other benefits (e.g., recreation, education, aesthetic appreciation, greenhouse gas retention). We found the five edge-of-field practices were all effective at removing nitrate with varying degrees of other potential benefits and disservices (e.g., greenhouse gas production). Drainage water recycling and water quality wetlands have the potential to provide the most co-benefits as they provide surface water systems for capturing surface flows in addition to tile drainage while also potentially providing habitat and recreation opportunities. However, the following research needs are identified: 1) the disservices and benefits associated with drainage water recycling have not been adequately evaluated; 2) surface flow dynamics are understudied across all reviewed management practices; 3) a complete accounting of phosphorus species and flow pathways for all management practices is needed; 4) field evaluations of the habitat benefit of all management practices are needed; and 5) greenhouse gas dynamics are understudied across all management practices. While all management practices are expected to reduce nitrate loads, addressing these knowledge gaps will help inform holistic management decisions for diverse stakeholders across the US Corn Belt., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Wind energy is widely deployed and will likely grow in service of reducing the world's dependency on fossil fuels. The first generation of wind turbines are now coming to the end of their service lives, and there are limited options for the reuse or recycling of the composite materials they are made of. Current literature has verified that there is no existing recycling pathway (i.e., mechanical, chemical, thermal methods of recovery, etc.) for end-of-life materials in wind blades that can meet cost parity with landfilling in the US. However, to the authors' knowledge there is no study to date that uncovers the cost structures associated with repurposing wind turbine blades in the US. Repurposing could offer a cost-competitive advantage through displacement of higher-value products, rather than materials or chemical constituents alone. This study implements life cycle assessment (LCA) and life cycle cost analysis (LCC) to assess the environmental and financial implications at each stage of repurposing wind turbine blades as the primary load-carrying elements for high-voltage transmission line structures in the United States. This case study contribution to knowledge is based on the successful management of construction waste by analyzing an application for repurposing construction demolition waste. Specifically, this study presents an environmental and financial analysis of repurposing wind turbine blades as transmission line poles. Under this case study, our results show that BladePoles have lower greenhouse gas emissions than steel poles, and we anticipate BladePoles will be less costly than steel poles. Overall emissions are most sensitive to combustion emissions, driven primarily by transportation distance and hours of required crane operations during the installation process. Compared to other evaluated recycling methods, repurposing wind blades as BladePoles has the least overall global warming potential. As renewable energy production grows, managing infrastructure at its end-of-life is increasingly relevant—for example, wind turbine blades. This case study presents a financial and environmental analysis of repurposing decommissioned wind turbine blades as transmission poles, called BladePoles. This paper presents the cost and associated greenhouse gas emissions at each stage of the process. The case study also compares this reuse application to typical steel pole deployment, finding that for the same 60-year life span and 161 kV, 230 kV, and 345 kV transmission line poles, the BladePole cost is lower than the steel pole. Greenhouse gas emissions are most sensitive to transportation distance from the wind farm to the transmission project and the time of crane use for installation are key parameters in this case study and reducing them directly reduces the total greenhouse emissions overall. [ABSTRACT FROM AUTHOR]

The article presents a study which focuses on the use of polar-focused approach to solar radiation management (SRM) to limit the pace of climatic changes in high latitudes. The study used the CAM3.1 atmospheric model coupled to a slab ocean from the National Center for Atmospheric Research. The study shows that green house gas emission is sufficient to limit the warming influence of greenhouse gas concentrations and polar reductions in solar radiation.

The impact of international trade on greenhouse gas (GHG) emissions has primarily been viewed through the lens of emissions embodied in goods, which flow from lower-income to higher-income countries. This trade has been interpreted as allowing the high-income countries to shirk their responsibilities to address the global climate challenge by offshoring emissions. However, international trade may also have an impact on climate through flows from higher-income to lower-income countries, particularly long-lived capital and durable goods that have the potential to avoid future emissions. Given the innovation resources concentrated in higher-income countries and their historic domination of trade in such long-lived goods, this concept may balance the scales to some degree. This paper briefly develops the concept of future avoided emissions and illustrates it with the empirical case of the United States' trade in battery electric vehicles (BEVs) from 2017 to 2020., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Transportation network companies (TNCs), such as Uber and Lyft, have pledged to fully electrify their ridesourcing vehicle fleets by 2030 in the United States. In this paper, we introduce AgentX, a novel agent-based model built in Julia for simulating ridesourcing services with high geospatial and temporal resolution. We then instantiate this model to estimate the life cycle air pollution, greenhouse gas, and traffic externality benefits and costs of serving rides based on Chicago TNC trip data from 2019 to 2022 with fully electric vehicles. We estimate that electrification reduces life cycle greenhouse gas emissions by 40-45% (9-10¢ per trip) but increases life cycle externalities from criteria air pollutants by 6-11% (1-2¢ per trip) on average across our simulations, which represent demand patterns on weekdays and weekends across seasons during prepandemic, pandemic, and post-vaccination periods. A novel finding of our work, enabled by our high resolution simulation, is that electrification may increase deadheading for TNCs due to additional travel to and from charging stations. This extra vehicle travel increases estimated congestion, crash risk, and noise externalities by 2-3% (2-3¢ per trip). Overall, electrification reduces net external costs to society by 3-11% (5-24¢ per trip), depending on the assumed social cost of carbon.

For years, transportation and land use integration has been identified as important approaches for planners, engineers, and designers, but to understand more research is needed to understand how it affects people who live around stations. In response, this research builds on a multi-year analysis quantitative and qualitative study of 2323 transit stations in over 350 corridors throughout the U.S. – one of the largest federally funded studies on livability related to transportation. This effort yielded empirical links to transportation and land use integration and quality of life outcomes. This paper concludes that the intersection between successful transportation and land use integration (TLI) depends on people's ability to equitably access opportunities to improve and/or maintain their desired quality of life. Along these lines this paper (a) identifies important characteristics (metrics) of TLI in 2323 transit station areas in the United States, (b) applies these metrics toward the development of a typology of station types (TOD), and then (c) validates these metrics by geo-locating a variety of quality of life outcomes for station area residents. Put simply, this paper finds that opportunity access can be an organising principle for guiding transportation and land use integration strategies. In turn, providing individuals with equitable access to opportunities measurably shows significant potential for achieving many societal and individual quality of life benefits such as lowering auto-dependency, household budget burdens, greenhouse gas emissions, and even poverty and obesity rates. [ABSTRACT FROM AUTHOR]

Several EU countries import wood pellets from the south-eastern United States. The imported wood pellets are (co-)fired in power plants with the aim of reducing overall greenhouse gas ( GHG) emissions from electricity and meeting EU renewable energy targets. To assess whether GHG emissions are reduced and on what timescale, we construct the GHG balance of wood-pellet electricity. This GHG balance consists of supply chain and combustion GHG emissions, carbon sequestration during biomass growth and avoided GHG emissions through replacing fossil electricity. We investigate wood pellets from four softwood feedstock types: small roundwood, commercial thinnings, harvest residues and mill residues. Per feedstock, the GHG balance of wood-pellet electricity is compared against those of alternative scenarios. Alternative scenarios are combinations of alternative fates of the feedstock materials, such as in-forest decomposition, or the production of paper or wood panels like oriented strand board ( OSB). Alternative scenario composition depends on feedstock type and local demand for this feedstock. Results indicate that the GHG balance of wood-pellet electricity equals that of alternative scenarios within 0-21 years (the GHG parity time), after which wood-pellet electricity has sustained climate benefits. Parity times increase by a maximum of 12 years when varying key variables (emissions associated with paper and panels, soil carbon increase via feedstock decomposition, wood-pellet electricity supply chain emissions) within maximum plausible ranges. Using commercial thinnings, harvest residues or mill residues as feedstock leads to the shortest GHG parity times (0-6 years) and fastest GHG benefits from wood-pellet electricity. We find shorter GHG parity times than previous studies, for we use a novel approach that differentiates feedstocks and considers alternative scenarios based on (combinations of) alternative feedstock fates, rather than on alternative land uses. This novel approach is relevant for bioenergy derived from low-value feedstocks. [ABSTRACT FROM AUTHOR]

Recently, many studies have assessed the carbon footprint of bovine milk production. However, due to the complexity of life cycle assessment, most studies have analyzed research farms or "representative" farms, which do not capture farm variability. Furthermore, the lack of consistency in most studies means that we can seldom compare the footprint between different countries. To address this issue, we performed a systematic review of the literature, removing inconsistencies in life cycle assessment papers, namely the functional unit, allocation to milk, and global warming potential. We analyzed papers that accounted for many farms to address the variability of production systems within the countries. We found 21 papers from 19 countries; footprint recalculations were necessary for 16 papers. New Zealand, Uruguay, the United Kingdom, Australia, and the United States had a footprint <1 kg of carbon dioxide equivalents (CO 2 e) per kilogram of fat- and protein-corrected milk, whereas 5 countries had a footprint >2 kg CO 2 e·kg -1 fat- and protein-corrected milk. The change in functional unit resulted in a small effect on the final footprint, whereas the global warming potential change was dependent in on the greenhouse gas profile for each country. Countries where milk is produced mainly as a pasture-based system had most of their footprint (>50%) associated with the emission of methane from enteric fermentation, whereas other countries (especially from Europe and North America) had a significant share of emissions from manure management, feed production, and fertilizer use. This different greenhouse gas profile allow decision makers to tailor mitigation options specific for each country. The choice of the allocation method had a strong influence in the final footprint. We suggest that for future studies, authors adhere to the International Dairy Federation guidelines. When this is not possible, we suggest a set of extra information to be reported, allowing recalculations as done in this review., (The Authors. Published by Elsevier Inc. and Fass Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).)

The article reports that the plastic industry and the American Chemistry Council (ACC) are under pressure in the U.S. government's ban of plastic bags. According to ACC senior director of packaging Keith Christman, paper bags create 50% more greenhouse gas emissions than plastic bags and plastic bags generate 80% less waste than paper bags. He adds that most grocery stores in the country oppose the legislation because paper bags cost more.

The widespread demand for animal-sourced foods poses challenges in addressing climate change due to their significant greenhouse gas emissions. Alternative proteins like cultured meat show promise with lower greenhouse gas emissions, but have faced public resistance, posing substantial barriers to their broad development and adoption. This paper reports a survey that examined the perceived naturalness of protein sources as an important factor that predicts perceived risks, benefits, and support for consumption. A diverse sample from the United States considered six different protein technologies, including three newer alternative proteins such as cultured meat and three more conventional proteins. Newer alternative proteins were perceived as less natural and were less supported than conventional proteins. Additionally, the more participants perceived protein sources as natural, the less risky and more beneficial they perceived them to be, contributing to their support. These results suggest that perceived naturalness, and associated risks and benefits, could be an important factor in shaping public support for or opposition to new proteins. These findings have theoretical and broader implications for the development and adoption of sustainability technologies. [ABSTRACT FROM AUTHOR]

The recently enacted Inflation Reduction Act (IRA) includes a number of incentive-based programs (e.g., tax credits) designed to motivate firms to develop new clean technologies for fighting climate change. However, the IRA also includes a fee firms incur for excessive methane emissions. This represents the first time the United States government has ever levied a fee on greenhouse gas emissions, and it raises an interesting research question—how should a budget-constrained regulator balance the use of both incentive and penalty-based levers for stimulating investment in clean technology development? In this paper, we examine a regulator's optimal penalty and subsidy decisions for motivating firms to invest in clean technology development. We illustrate how the level of competitive intensity in the market can influence a budget-constrained regulator with multiple competing objectives—the environment, firm profits, and consumer welfare. We find that a subsidy is always beneficial, irrespective of the regulator's objective. While imposing a firm penalty always benefits the environment, it always negatively impacts the sum of firm profits and consumer welfare. However, depending on the level of competition in the market, instances can occur where imposing a high penalty actually benefits total firm profits or consumer welfare (separately). Interestingly, a regulator that cares about all three dimensions of its objective equally, should always set the penalty to either its minimum or maximum value, depending on whether the environmental cost of the harmful product is high or low. [ABSTRACT FROM AUTHOR]

Higher fuel economy standards and more stringent limitations on greenhouse gas emissions for ground vehicles have been made due to public concerns about energy crisis and environmental issues. By organizing a group of automated vehicles into a platoon at a short intervehicular distance, the overall fuel consumption and greenhouse gas emissions of vehicle platoon can be decreased due to reduced aerodynamic drag, which is called the platooning technology. In addition, the eco-driving technology can help further increase the fuel efficiency of vehicle platoon by optimizing speed trajectories of vehicles. However, little research has been done into the combination of the eco-driving and platooning technologies. Based on distributed model predictive control (DMPC), this paper proposes an ecological cooperative look-ahead control strategy for a platoon of automated vehicles travelling on a freeway with varying slopes, where both the eco-driving and platooning technologies are used. To maximize the fuel efficiency of vehicle platoon, an ecological cooperative look-ahead control problem (Eco-CLC) is first formulated based on DMPC, where rotational inertia coefficient related to reduction ratio of gear box, aerodynamic drag related to spacing and model constraints are considered. Since the Eco-CLC problem is a nonconvex and nonlinear optimization problem with hard state constraints, it is very difficult to quickly obtain its optimal solution. To enhance real-time control performance, after the hard state constraints of the Eco-CLC problem are transformed into parts of the multi-objective function using the band-stop function, the improved ecological cooperative look-ahead control (iEco-CLC) based on DMPC is given. A particle swarm optimization algorithm with multiple dynamic populations is further presented to quickly solve the iEco-CLC problem online. Simulation results demonstrate, compared with benchmarks, the proposed strategy can save more than 21% of fuel for vehicle platoon. [ABSTRACT FROM AUTHOR]

A critical examination of the US Environmental Protection Agency's (US EPA's) Greenhouse Gas Reporting Program (GHGRP) database provided an opportunity for the largest evaluation to date of landfilled waste decomposition kinetics with respect to different US climate regimes. In this paper, 5-8 years of annual methane collection data from 114 closed landfills located in 29 states were used to estimate site-specific waste decay rates (k) and methane collection potentials (Lc). These sites account for approximately 9% of all landfills required to report GHG emissions to the US EPA annually. The mean methane collection potential (Lc) for the sites located in regions with less than 635 mm (25 in) annual rainfall was significantly (p<0.002) lower than the mean methane collection potential of the sites located in regions with more than 635 mm (25 in) annual precipitation (49 and 73 m3 methane Mg-1 waste, respectively). This finding suggests that a fraction of the in-place biodegradable waste may not be decomposing, potentially due to a lack of adequate moisture content of landfills located in arid regions. The results of this evaluation offer insight that challenges assumptions of the traditional landfill methane estimation approach, especially in arid climates, that all methane corresponding to the total methane generation potential of the buried solid waste will be produced. Decay rates showed a significant correlation with annual precipitation, with an average k of 0.043 year-1 for arid regions (< 508 mm (20 in) year-1), 0.074 year-1 for regions with 508-1,016 mm (20-40 in) annual precipitation, and 0.09 year-1 in wet regions (> 1,016 mm (40 in) year-1). The data suggest that waste is decaying faster than the model default values, which in turn suggests that a larger fraction of methane is produced during a landfill's operating life (relative to post-closure)., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The employment of Pradeep Jain and James Wally with Innovative Waste Consulting Services LLC does not alter our adherence to PLOS ONE policies on sharing data and materials.

Residential energy demand can be greatly influenced by the types of housing structures that households live in, but few studies have assessed changes in the composition of housing stocks as a strategy for reducing residential energy demand or greenhouse gas (GHG) emissions. In this paper we examine the effects of three sequenced federal policies on the share of new housing construction by type in the U.S., and estimate the cumulative influence of those policies on the composition of the 2015 housing stock. In a counterfactual 2015 housing stock without the policy effects, 14 million housing units exist as multifamily rather than single-family, equal to 14.1% of urban housing. Accompanied by floor area reductions of 0-50%, the switch from single- to multifamily housing reduces energy demand by 27-47% per household, and total urban residential energy by 4.6-8.3%. This paper is the first to link federal policies to housing outcomes by type and estimate associated effects on residential energy and GHG emissions. Removing policy barriers and disincentives to multifamily housing can unlock a large potential for reducing residential energy demand and GHG emissions in the coming decades.

Increasing energy consumption in the transportation sector results in challenging greenhouse gas (GHG) emissions and environmental problems. This paper involved integrated assessments on GHG emissions and emergy of the life cycle for the internal combustion engine (ICE) and electric automobiles in the USA over the entire assumed fifteen-year lifetime. The hotspots of GHG emissions as well as emergy indices for the major processes of automobile life cycle within the defined system boundaries have been investigated. The potential strategies for reducing GHG emissions and emergy in the life cycle of both ICE and electric automobiles were further proposed. Based on the current results, the total GHG emissions from the life cycle of ICE automobiles are 4.48E + 07 kg CO 2 -e which is 320 times higher than that of the electric automobiles. The hotspot area of the GHG emissions from ICE and electric automobiles are operation phase and manufacturing process, respectively. Interesting results were observed that comparable total emergy of the ICE automobiles and electric automobiles have been calculated which were 1.54E + 17 and 2.20E + 17 sej, respectively. Analysis on emergy index evidenced a better environmental sustainability of electric automobiles than ICE automobiles over the life cycle due to its higher ESI. To the authors' knowledge, it is the first time to integrate the analysis of GHG emissions together with emergy in industrial area of automobile engineering. It is expected that the integration of emergy and GHG emissions analysis may provide a comprehensive perspective on eco-industrial sustainability of automobile engineering., (Copyright © 2020. Published by Elsevier B.V.)

Construction of commercial buildings has an environmental impact because of emissions from nonroad equipment. Construction produces 7% of the U.S. greenhouse gas emissions, of which 76% originates from engines. However, there has not been an established methodology for estimating construction activity emissions at the project level for buildings and other constructed facilities. Therefore, determining where and when construction produces emissions is important, necessitating that emissions inventories (i.e., databases of project emissions by type, cost, etc.) be developed to quantify these emissions. The pollutants addressed in this paper include carbon dioxide (CO2), nitrogen oxides (NOx), total hydrocarbons (THC), carbon monoxide (CO), particulate matter (PM), and sulfur dioxide (SO2). This paper presents a methodology that provides a direct link between building construction activities and emissions. The use of this methodology is demonstrated for a commercial building case study, thereby providing quantified emissions predictions for various levels of detail (i.e., construction activity, construction cost division, and overall project). Using this methodology, both fuel use and emissions can be determined at any stage of the planning, designing, and building process with increasing levels of precision being obtained as the project progresses. The methodology demonstrates the ability to link key quantitative indicators of specific building construction activities to emission rates for specific types of equipment used in construction. The case study results illustrate that emissions during construction are highly episodic, with site work activities and equipment contributing large proportions of overall project emissions. [ABSTRACT FROM AUTHOR]

Estimates of the marginal value of carbon dioxide-the social cost of carbon (SCC)-were recently adopted by both the U.S. and U.K. Governments in order to satisfy requirements to value estimated greenhouse gas (GHG) changes of new federal regulations. However, the development and use of SCC estimates comes with significant challenges and controversial decisions. This paper summarizes the key issues and then derives guidance for developing, selecting, and applying the estimates that follows from the fundamental scientific nature and economic principles associated with GHGs and climate change, as well as an understanding of the state of the art for estimating the SCC. The paper evaluates recent estimates in light of the guidance and finds the estimates inconsistent with the guidance in a number of significant areas. The paper also differentiates SCC policy applications in terms of policies with incremental versus nonincremental implications for global GHGs, and identifies serious issues for application of the SCC in setting and evaluating climate policy targets. WIREs Clim Change 2012, 3:163-195. doi: 10.1002/wcc.163 For further resources related to this article, please visit the . [ABSTRACT FROM AUTHOR]

This paper quantifies and compares the life cycle GHG emissions and costs of production of diesel and jet fuel derived from municipal solid waste (MSW) in the United States via three thermochemical conversion pathways: conventional gasification and Fischer-Tropsch (FT middle distillate, MD), plasma gasification and Fischer-Tropsch (Plasma FT MD), and conventional gasification, catalytic alcohol synthesis, and alcohol-to-jet upgrading (ATJ MD). We use expanded system boundaries to capture the change in existing MSW use and disposal, and account for parameter uncertainty with Monte Carlo simulations. We estimate median life cycle GHG emissions of 32.9, 62.3, and 52.7 gCO 2 e/MJ for FT, Plasma FT and ATJ MD fuels, respectively, compared to a baseline of 90 gCO 2 e/MJ for conventional MD fuels. Median minimum selling prices are estimated at 0.99, 1.78, and 1.20 $ per liter with the probability of achieving a positive net present value of fuel production at market prices of 14%, 0.1% and 7% for FT, Plasma FT and ATJ MD fuels, respectively. If the societal perspective rather than an investor's perspective is evaluated, then the probability of positive net present value of fuel production increases to 93%, 67%, and 92.5% for the FT, Plasma FT, and ATJ MD fuels, respectively.

This paper examines hydrological variability and its changes in two different versions of a coupled ocean–atmosphere general circulation model developed at the National Oceanic and Atmospheric Administration/Geophysical Fluid Dynamics Laboratory and forced with estimates of future increases of greenhouse gas and aerosol concentrations. This paper is the second part, documenting potential changes in variability as greenhouse gases increase. The variance changes are examined using an ensemble of 8 transient integrations for an older model version and 10 transient integrations for a newer model. Monthly and annual data are used to compute the mean and variance changes. Emphasis is placed on computing and analyzing the variance changes for the middle of the twenty-first century and compared with those found in the respective control integrations. The hydrologic cycle intensifies because of the increase of greenhouse gases. In general, precipitation variance increases in most places. This is the case virtually everywhere the mean precipitation rate increases and many places where the precipitation decreases. The precipitation rate variance decreases in the subtropics, where the mean precipitation rate also decreases. The increased precipitation rate and variance, in middle to higher latitudes during late fall, winter, and early spring leads to increased runoff and its variance during that period. On the other hand, the variance changes of soil moisture are more complicated, because soil moisture has both a lower and upper bound that tends to reduce its fluctuations. This is particularly true in middle to higher latitudes during winter and spring, when the soil moisture is close to its saturation value at many locations. Therefore, changes in its variance are limited. Soil moisture variance change is positive during the summer, when the mean soil moisture decreases and is close to the middle of its allowable range. In middle to high northern latitudes, an increase in runoff and its variance during late winter and spring plus the decrease in soil moisture and its variance during summer lend support to the hypothesis stated in other publications that a warmer climate can cause an increasing frequency of both excessive discharge and drier events, depending on season and latitude. [ABSTRACT FROM AUTHOR]

The challenge of reducing emissions of greenhouse gases (GHG) has stimulated great attention among policymakers and scholars in recent past, and a number of STIRPAT (Stochastic Impacts by Regression on Population, Affluence, and Technology) studies on carbon emissions have been conducted. This paper contributes to that literature by: (i) studying per capita GHG emissions in the United States (US) adopting STIRPAT modeling framework; (ii) employing new explanatory factors like cattle population density, political willingness to address environmental problems, and educational attainment; and (iii) investigating whether emissions elasticities of various factors vary within the US or not. State-level panel data over the period 1990–2014 are used, and partitioning of the sample is done with respect to two controlling factors: an indicator of political support to environmentalism and educational attainment. Results of heterogeneous slope parameters panel data models indicate that cattle density and affluence are major drivers of per capita GHG emissions in the continental US. We find strong evidence of heterogeneity in emissions elasticities across partitioned samples. Our grouping analysis suggests that in a diverse country like US, policymakers should not focus on the average relationships dictated by a single STIRPAT equation, but should account for regional differences if they want accuracy and higher effectiveness in climate policymaking. [ABSTRACT FROM AUTHOR]

This article reflects on the article "A Robust Strategy for Sustainable Energy," by Klaus S. Lackner and Jeffrey D. Sachs. The author agrees with the conclusion of the article which states that there is no shortage of energy on the horizon. It points out that the debate over the exhaustion of liquid fuels is mostly based on false premises. But the author feels a more complete discussion of the making of liquid fuel from biomass was missing from the article. Biomass, which would compete for land with food producers, and biomass such as corn stalks which can be used to create fuel. Lackner's and Sach's article constructs a baseline scenario for greenhouse gas emissions over the next century on the basis of an assumed convergence of income per capita around the world on income per capita in the United States.

Small modular reactors (SMRs) provide a unique opportunity for future nuclear development with reduced financial risks, allowing the United States to meet growing energy demands through safe, reliable, clean air electricity generation while reducing greenhouse gas emissions and the reliance on unstable fossil fuel prices. A nuclear power plant is comprised of several complex subsystems which utilize materials from other subsystems and their surroundings. The economic utility of resources, or thermoeconomics, is extremely difficult to analyze, particularly when trying to optimize resources and costs among individual subsystems and determine prices for products. Economics and thermodynamics cannot provide this information individually. Thermoeconomics, however, provides a method of coupling the quality of energy available based on exergy and the value of this available energy - "exergetic costs". For an SMR exergy analysis, both the physical and economic environments must be considered. The physical environment incorporates the energy, raw materials, and reference environment, where the reference environment refers to natural resources available without limit and without cost, such as air input to a boiler. The economic environment includes market influences and prices in addition to installation, operation, and maintenance costs required for production to occur. The exergetic cost or the required exergy for production may be determined by analyzing the physical environment alone. However, to optimize the system economics, this environment must be coupled with the economic environment. A balance exists between enhancing systems to improve efficiency and optimizing costs. Prior research into SMR thermodynamics has not detailed methods on improving exergetic costs for an SMR coupled with storage technologies and renewable energy such as wind or solar in a hybrid energy system. This process requires balancing technological efficiencies and economics to demonstrate financially competitive systems. This paper aims to explore the use of exergy analysis methods to estimate and optimize SMR resources and costs for individual subsystems, based on thermodynamic principles - resource utilization and efficiency. The paper will present background information on exergy theory; identify the core subsystems in an SMR plant coupled with storage systems in support of renewable energy and hydrogen production; perform a thermodynamic exergy analysis; determine the cost allocation among these subsystems; and calculate unit exergetic costs, unit exergoeconomic costs, and first and second law efficiencies. Exergetic and exergoeconomic costs ultimately determine how individual subsystems contribute to overall profitability and how efficiencies and consumption may be optimized to improve profitability, making SMRs more competitive with other generation technologies. [ABSTRACT FROM AUTHOR]

Climate change, originating from greenhouse gas emissions, yields profound implications such as escalated temperatures, severe storms, disruptions in food supply chains, and amplified seismic activity, particularly impacting arid regions. As the world's largest economy and the second-largest CO2 emitter, the United States actively leads initiatives aimed at addressing environmental challenges and aligning with the United Nations' Sustainable Development Goals (SDGs) 7 and 13. This study delves into the determinants shaping renewable energy consumption and CO2 emissions within the United States, aiming to elucidate their pivotal role in advancing carbon neutrality efforts. Using quarterly data spanning from 1990 to 2020, this investigation employs the time-varying TVP-SV-VAR model to dissect the dynamic interplay among these variables. The findings reveal intricate connections across short, medium, and long-term periods: renewable energy adoption, eco-innovations, and uncertainties in climate policy were observed to mitigate CO2 emissions. Conversely, financial development exhibited a consistent association with increased CO2 emissions across all timeframes. Additionally, the progression of renewable energy sources showcased responsiveness to climate policy uncertainties, eco-innovations, and financial development across each timeframe. These outcomes hold substantial implications for the United States' pursuit of carbon neutrality goals, emphasizing the pivotal role of promoting renewable energy initiatives. [ABSTRACT FROM AUTHOR]

Despite global efforts to harmonize international trade statistics, our understanding of digital trade and its implications remains limited. Here, we introduce a method to estimate bilateral exports and imports for dozens of sectors starting from the corporate revenue data of large digital firms. This method allows us to provide estimates for digitally ordered and delivered trade involving digital goods (e.g. video games), productized services (e.g. digital advertising), and digital intermediation fees (e.g. hotel rental), which together we call digital products. We use these estimates to study five key aspects of digital trade. We find that, compared to trade in physical goods, digital product exports are more spatially concentrated, have been growing faster, and can offset trade balance estimates, like the United States trade deficit on physical goods. We also find that countries that have decoupled economic growth from greenhouse gas emissions tend to have larger digital exports and that digital exports contribute positively to the complexity of economies. This method, dataset, and findings provide a new lens to understand the impact of international trade in digital products. This study introduces a method to quantify trade in digital products, like cloud computing and mobile games. It finds that this trade grows rapidly, may impact trade balances, support economic decoupling, and enhance economic complexity measures. [ABSTRACT FROM AUTHOR]

Planetary Health emphasises the sustainability of natural systems for human well-being, linking human health directly with environmental health. This interdisciplinary concept has gained importance as anthropogenic activities have led to climate changes and health impacts. Despite efforts, a cohesive approach to planetary health from local to global levels remains lacking. The present review analysed 24 sources, including grey literature and published studies, identifying 40 interventions aimed at improving planetary health. The majority of research, primarily from the United States, focuses on reducing air pollution and greenhouse gas emissions. Effective strategies highlighted include promoting active transportation, improving diets, increasing physical activity, and engaging with indigenous communities to protect both environmental and human health. However, a significant gap exists in integrating these interventions through a unified informatics tool, which could enhance coordination and implementation of planetary health measures globally. The review underscores the necessity for a more integrated approach and the development of a global database to consolidate and manage planetary health interventions effectively. [ABSTRACT FROM AUTHOR]

Purpose: Fuel economy and emissions of heavy-duty trucks greatly vary based on vehicular/environmental conditions. Large-scale infrastructure construction projects require a large amount of material/equipment transportation. Single-parameter generic hauling models may not be the best option for an accurate estimation of hauling contribution in life cycle assessment (LCA) involving construction projects; therefore, more precise data and parameterized models are required to represent this contribution. This paper discusses key environmental/operational variables and their impact on transportation of materials and equipment; a variable-impact transportation (VIT) model accounting for these variables was developed to predict environmental impacts of hauling. Methods: The VIT model in the form of multi-nonlinear regression equations was developed based on simulations using the U.S. Environmental Protection Agency (EPA)'s Motor Vehicle Emission Simulator (MOVES) to compute all the impact categories in EPA's TRACI 2.1 and energy consumption of transportation. Considering actual driving cycles of hauling trucks recorded during a pavement rehabilitation project, the corresponding environmental impacts were calculated, and sensitivity analyses were performed. In addition, an LCA case study based on historical pavement reconstruction projects in Illinois was conducted to analyze the contribution of transportation and variability of its impacts during the pavements' life cycle. Results and discussion: The importance of vehicle driving cycles was realized from simulation results. The case study results showed that considering driving cycles using the VIT model could increase the contribution of hauling in total life cycle Global Warming Potential (GWP) and total life cycle GWP itself by 2–4 and 3–5%, respectively. In addition to GWP, ranges of other hauling-related impact categories including Smog, Ozone Depletion, Acidification, and Primary Energy Demand from fuel were presented based on the case study. Ozone Depletion ranged from 9 to 45%, and Smog ranged from 11 to 48% of the total relevant life cycle impacts. The GWP contribution of hauling in pavement LCA ranged between 5 and 32%. The results indicate that the contribution of hauling transportation can be significant in pavement LCA. Conclusions: For large-scale roadway infrastructure construction projects that need a massive amount of material transportation, high fidelity models and data should be used especially for comparative LCAs that can be used as part of decision making between alternatives. The VIT model provides a simple analytical platform to include the critical vehicular/operational variables without any dependence on an external software; the model can also be incorporated in those studies where some of the transportation activity data are available. [ABSTRACT FROM AUTHOR]

Heavy-duty vehicles contribute a significant and increasing portion of global greenhouse gas emissions. The objective of this study is to provide an overview of heavy-duty vehicle efficiency policies in major markets to better inform the global evolution of climate mitigation measures. The paper compiles information from those four nations that have adopted some form of heavy-duty vehicle fuel economy standards-China Japan, United States of America (USA), and Canada-plus the European Union. Despite widespread differences, the study finds that each jurisdiction used simulation modeling to some extent to minimize the cost of chassis-based compliance testing. Further, the study identified several common elements under development for the next round of policies, including (1) how to incorporate trailer manufacturers into existing regulatory structures, (2) how to add new test procedures to fully account for potential benefits from hybrids and advanced transmissions, and (3) how to address the tension between separate test procedures for fuel economy and conventional pollutants. The paper concludes with a discussion of opportunities and challenges for aligning national policies in the future. [ABSTRACT FROM AUTHOR]

Available estimates of the land use changes and greenhouse gas emissions of biofuels differ significantly across economic models. This paper focuses on the impacts of price-induced yield assumptions on U.S. corn ethanol results. These assumptions have dramatic impacts within the FAPRI modeling framework, but limited ones within the GTAP-BIO model. I show that these sensitivity to yield assumption results are not comparable because the ex ante land and production elasticities assumed in these two models are not comparable. The analysis reveals that the current focus solely on the value of the price-induced yield elasticity can be misleading. [ABSTRACT FROM AUTHOR]

The theory that we shall seek to elaborate here puts considerable emphasis on maintenance of biodiversity in agricultural landscapes, conventionalization of organic food systems, and the agricultural sector as both a source of GHG emissions and a potential tool for mitigation. This paper discusses the major trends in scholarship about the development of organic agriculture, the mitigation and adaptation potential of organic agricultural systems, and the practice of organic agriculture on a large scale. [ABSTRACT FROM AUTHOR]

We study 944 shareholder proposals submitted to 343 U.S. firms on climate change issues during 2009–2022. We use logistic and two-stage regression to estimate the propensity for a firm to be targeted or subjected to a vote at the annual general meeting and, for voted proposals, the determinants of that vote. We also examine whether climate-related proposals affect investor returns and how they relate to firms' future environmental performance and greenhouse gas emissions. Compared to a matched sample, we first find that activists target larger, more carbon-intensive, and less R&D-active firms. Second, voting likelihood is higher for firms with repeated and operations-related proposals and lower pre-proposal environmental ratings. By contrast, disclosure-related proposals are likelier to be negotiated and withdrawn. Third, repeated and operations-related proposals receive higher votes in favor, whereas votes on carbon-intensive firms do not. Fourth, building on the theory that investors act as if they distinguish among the different shareholder proposals based on the expected cost to the firm, we find evidence to support this idea. We find that investors respond negatively to ex-ante costlier proposals, such as those that relate to emissions reduction and target carbon-intensive firms. Fifth, targets' future environmental performance rating is almost twenty percent higher after a proposal than before compared to the matched sample, whereas emissions do not budge appreciably. [ABSTRACT FROM AUTHOR]

Background: The Planetary Health Diet Index (PHDI) measures adherence to the dietary pattern presented by the EAT-Lancet Commission, which aligns health and sustainability targets. There is a need to understand how PHDI scores correlate with dietary greenhouse gas emissions (GHGE) and how this differs from the carbon footprints of scores on established dietary recommendations. The objectives of this study were to compare how the PHDI, Healthy Eating Index-2015 (HEI-2015) and Dietary Approaches to Stop Hypertension (DASH) relate to (a) dietary GHGE and (b) to examine the influence of PHDI food components on dietary GHGE. Methods: We used life cycle assessment data from the Database of Food Recall Impacts on the Environment for Nutrition and Dietary Studies to calculate the mean dietary GHGE of 8,128 adult participants in the 2015–2016 and 2017–2018 cycles of the National Health and Nutrition Examination Survey (NHANES). Poisson regression was used to estimate the association of (a) quintiles of diet score and (b) standardized dietary index Z-scores with dietary GHGE for PHDI, HEI-2015, and DASH scores. In secondary analyses, we used Poisson regression to assess the influence of individual PHDI component scores on dietary GHGE. Results: We found that higher dietary quality on all three indices was correlated with lower dietary GHGE. The magnitude of the dietary quality-dietary GHGE relationship was larger for PHDI [-0.4, 95% CI (-0.5, -0.3) kg CO2 equivalents per one standard deviation change] and for DASH [-0.5, (-0.4, -0.6) kg CO2-equivalents] than for HEI-2015 [-0.2, (-0.2, -0.3) kg CO2-equivalents]. When examining PHDI component scores, we found that diet-related GHGE were driven largely by red and processed meat intake. Conclusions: Improved dietary quality has the potential to lower the emissions impacts of US diets. Future efforts to promote healthy, sustainable diets could apply the recommendations of the established DASH guidelines as well as the new guidance provided by the PHDI to increase their environmental benefits. [ABSTRACT FROM AUTHOR]

In preparing inventories of ozone-depleting substance (ODS) substitutes, primarily hydrofluorocarbons, the US employs models consistent with Tier 2 methodologies from the 2006 IPCC Guidelines for National Greenhouse Gas Inventories. The model calculates chemical consumption and emissions for 60 sub-applications, which are aggregated to five application levels. So-called “bottom-up” models require data and assumptions regarding the sub-application industries, including number of products introduced and retired each year, the type and amount of chemicals initially used, the emission pattern of the chemicals and if any released chemical is replaced. Once developed, the bottom-up model's estimates of chemical demand can be compared to “top-down” chemical consumption or sales. Combining these types of data gives a partial picture of the amount of ODS and substitutes introduced to the US economy. This paper examines the top-down data in comparison to the bottom-up estimates derived from the inventory models and discusses possible explanations for the differences noted. [ABSTRACT FROM AUTHOR]

Much of the attention surrounding local climate protection in the United States is associated with two networks: ICLEI Local Governments for Sustainability's Cities for Climate Protection and the U. S. Conference of Mayors' Climate Protection Agreement ( MCPA). However, the impact of these networks on member-city actions has not been clearly established. This paper examines whether, and to what extent, participation in climate networks leads to the implementation of greenhouse gas ( GHG)-reducing policies, above and beyond what would have been done in their absence. To account for the possibility that cities which join climate networks are systematically different from those that do not and control for self-selection induced bias, three statistical techniques-propensity score matching, Heckman full information maximum likelihood, and instrumental variables-are employed to estimate the 'treatment effect' of participation. Results suggest that impact is network specific: ICLEI membership causes small to moderate increases in cities' GHG-relevant activity, whereas the MCPA has no such effect. The characteristics of each network are evaluated in light of these findings. [ABSTRACT FROM AUTHOR]

It is essential to maintain global measurements of the earth radiation budget (ERB) from space, the scattered solar and emitted thermal radiative fluxes leaving the planet. These are required for the purpose of validating current climate model predictions of the planet’s future response to anthropogenic greenhouse gas forcing. The measurement accuracy and calibration stability required to resolve the magnitude of model-suggested cloud–climate feedbacks on the ERB have recently been estimated. The suggestion is for ERB data to strive for a calibration stability of ±0.3% decade-1 for scattered solar, ±0.5% decade-1 for emitted thermal, and an overall absolute accuracy of 1 W m-2. The Clouds and the Earth’s Radiant Energy System (CERES) is currently the only satellite program to make global ERB measurements, beginning in January 1998. However, the new climate calibration standards are beyond those originally specified by the NASA CERES program for its edition 2 data release. Furthermore, the CERES instrument optics have been discovered to undergo substantial in-flight degradation because of contaminant issues. This is not directly detectable by using established calibration methods. Hence, user-applied revisions for edition 2 shortwave (SW) data were derived to compensate for this effect, which is described as “spectral darkening.” Also, an entirely new in-flight calibration protocol has been developed for CERES that uses deep convective cloud albedo as a primary solar wavelength stability metric. This is then combined with a sophisticated contamination mobilization/polymerization model. The intention is to assign spectral coloration to any optical degradation occurring to the different CERES Earth observing telescopes. This paper quantifies the stability of revised edition 2 data. It also calculates stability, which the new protocols could give CERES measurements if used. The conclusion is that the edition 2 revisions restore the originally specified stability of CERES SW data. It is also determined that the climate calibration stability goals are reachable by using the new in-flight methodologies presented in this paper. However, this will require datasets of longer than approximately 10 yr. It will also require obtaining regular raster scans of the Moon by all operational CERES instruments. [ABSTRACT FROM AUTHOR]

Abstract: The likely centerpiece of U.S. legislation to address climate change will be a cap-and-trade program that creates a market for greenhouse gases (GHGs). Whether the onset of a cap-and-trade system and additional complementary policies would provide a benefit or a cost to our economy has been the subject of much modeling and debate. This paper argues that while climate policy does not come without cost, modeling of the Lieberman–Warner Climate Security Act demonstrates that these costs are not substantial and can be mitigated by appropriate policy design. Finally, while a well-designed carbon market will be a large factor in lowering costs and driving innovation, complementary policies will be necessary to induce the technological change required to transition the United States to a low-carbon economy. [Copyright &y& Elsevier]

Commercial windmill-driven power turbines (wind turbines') are expanding in popularity and use in the commercial power industry, since they can generate significant electricity without using fuel or emitting carbon-dioxide "greenhouse gas." In- country and near-off-shore wind turbines are becoming more common on the European continent. The United States has recently set long-term goals to generate 10% of national electric power using renewable sources. In order to make such turbines efficient, current 1.5 MW wind-turbine towers and rotors are very large, with blades exceeding 67 m in diameter, and tower heights exceeding 55 m. Newer 4.5 MW designs are expected to be even larger. The problem with such large, moving, metallic devices is the potential interference such structures present to an array of civilian air-traffic-control radars. A recent study by the Undersecretary of Defense for Space and Sensor Technology acknowledged the potential performance impact wind turbines introduce when located within line of site of air-traffic-control or air-route radars [1]. In the spring of 2006, the Air Force Research Laboratory embarked on a rigorous measurement and prediction program to provide credible data to national decision makers on the magnitude of the signatures, so that the interference issues could be credibly studied. This paper, the first of two parts, will discuss the calibrated RCS measurement of the turbines, and compare this data (with its uncertainty) to modeled data. [ABSTRACT FROM AUTHOR]

In this paper, we study empirically whether uncertainty has an influence on trade in the US sulfur dioxide allowances market. In particular, we investigate the role of uncertainty on banking behavior. To do this, we introduce a tractable, structural model of trading permits under uncertainty. The model establishes a relation between banking behavior and risk preferences, especially prudence in the Kimball () sense. We then test this model using data on allowances, for utilities submitted to the US Environmental Protection Agency’s Acid Rain Program, carried over from one year to the next. Evidence is found of imprudence, namely, utilities bank permits in order to favor higher profits. Another finding is that larger utilities do not adopt behavior significantly different from that of smaller ones. [ABSTRACT FROM AUTHOR]

This paper provides comparisons of a variety of time-series methods for short-run forecasts of the main greenhouse gas, carbon dioxide, for the United States, using a recently released state-level data set from 1960–2001. We test the out-of-sample performance of univariate and multivariate forecasting models by aggregating state-level forecasts versus forecasting the aggregate directly. We find evidence that forecasting the disaggregate series and accounting for spatial effects drastically improves forecasting performance under root mean squared forecast error loss. Based on the in-sample observations we attempt to explain the emergence of voluntary efforts by states to reduce greenhouse gas emissions. We find evidence that states with decreasing per capita emissions and a “greener” median voter are more likely to push toward voluntary cutbacks in emissions. [ABSTRACT FROM AUTHOR]

The Kyoto agreement as originally drafted sought to mitigate anthropogenic greenhouse gas emissions through policy measures by most industrialized countries. It now seems likely that the agreement will be ratified and implemented without the participation of the United States. Any emissions abatement policies which have a measurable reduction in global emissions will induce changes in the terms of trade and comparative advantage and competitiveness To the extent that aggressive policies are undertaken to reduce CO2 emissions, there are likely to be strong calls in the Kyoto coalition for greenhouse-gas related border adjustment measures. This paper uses a multi-region, multi-commodity static general equilibrium model to quantify and assess the implications of such policies. [ABSTRACT FROM AUTHOR]