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Electric ships are becoming a promising way in shipping decarbonization. Nevertheless, the promotion of electric ships encounters obstacles related to indirect emissions, energy and costs. This paper proposes the Shipping Emission-Energy-Economic Impact Assessment Model (SE3IAM) to assess the decarbonization potential of electric ships. China is selected for the case study. This paper also analyzes the impact of climate policies and other factors on CO 2 emissions. Results indicate that as the market share of electric ships gradually reaches 1%, 20%, and 35% by 2050, accompanied by advancements in other technological aspects, the total emissions to 2050 are estimated to be around 2, 1.5, and 1 billion tons, respectively. There is a positive correlation between energy demand and decarbonization costs with the level of economic development. Technological progress can alleviate pressures on energy and costs. It is recommended to advance decarbonization at a fundamental level by enhancing energy efficiency and fostering electrification. [ABSTRACT FROM AUTHOR]

Traffic oscillation, a traffic phenomenon that generates many carbon emissions, originates from the amplification of traffic disturbance. The connected and automated vehicle (CAV) technology may help to weaken oscillations and reduce carbon emissions from mixed traffic. This paper explores the effects of various characteristics of disturbances and mixed platoons on CO 2 emissions under different disturbance types. The results indicate that the addition of even only one CAV reduces carbon emissions under some disturbances. The disturbance types that make mixed traffic increase carbon emissions have also been identified. Diverse disturbance characteristics play different essential roles in ecological impacts of CAVs. The platoon characteristics such as CAV's position in a platoon and the heterogeneity of human factors, affect the extent of carbon emission reduction. Based on these findings, this paper proposes optimization recommendations for CAV cooperative eco-driving and green traffic management. [ABSTRACT FROM AUTHOR]

Reverse logistics plays a critical role in sustainable development and circular economy by transforming waste into value. However, transporting large volumes of waste and recyclables generates significant carbon emissions. This paper explores an industry-led strategy for charging infrastructure development, which integrates the reverse logistics network designs with a network of charging stations to promote electric trucks (E-trucks) adoption and reduce carbon footprints in transportation. Our model optimizes operational costs while ensuring accessibility to charging infrastructure. A case study in Norway demonstrates that, despite higher operating costs due to additional charging stations, the adoption of E-trucks can decrease total reverse logistics costs by 0.18%—2.37% and cut carbon emissions by 16.3%—17.6%. These findings support the economic viability and environmental benefits of this strategy for advancing sustainable practices in transportation, and it further highlights the interdependencies between logistics network design and charging infrastructure planning. [ABSTRACT FROM AUTHOR]

• Assessment of ship emission performance under diverse decarbonization measures. • Technical options reduce more carbon and air pollutant emissions than operational. • Trade-offs between air pollutant reduction and decarbonization strategies. • Contribution in policies for reducing both carbon emissions and air pollutants. Shipping emits Greenhouse Gases (GHG), contributing to climate change and various air pollutants, posing risks on human health. To address GHG, maritime has responded with increasingly stringent legislations, including recent commitments to achieve net-zero emissions by 2050. Substantial investments have been made in cutting-edge technologies, alternative fuels and operational strategies ensuring emissions regulations compliance. This paper aims to quantitatively evaluate the emission performance of diverse decarbonization options, focusing on assessing their potential to mitigate GHG and addressing air pollutants. Our analysis utilizes a new set of load-dependent Emission Factors and employs Automatic Identification System data for 5 ship classes. While operational measures moderately reduce emissions, fuel shift to alternatives and on-board carbon capture and storage offer a more promising pathway towards decarbonization and air pollutants reduction. The outcomes intend to provide insights into the effectiveness of measures in reducing external costs, while serving as a valuable resource for regulatory authorities. [ABSTRACT FROM AUTHOR]

Online retail is characterized by an increasing emphasis on shorter delivery times, which often comes with high logistics costs and a negative environmental impact. Conversely, longer order fulfillment times improve cost and eco-efficiency. This paper investigates whether customers in German-speaking countries are willing to wait longer for their online orders in the fashion, shoes, and accessories sector when offered incentives in return. The research employed an online survey using a within-subjects design. Results indicate that incentives significantly extend customers' patience. Savings on shipping costs and information on the reduction in CO 2 emissions greatly impact willingness to wait. Personal traits like gender, age, eco-awareness, and order urgency affect incentive responses. This demonstrates customers' readiness to make trade-offs in delivery time and emphasizes the importance of explicitly addressing the ecological impact of delivery. Suggestions for online retailers and logistics include slower delivery choices and customized incentives aligned with target audience and market. • Empirical study on online fashion customers' willingness to accept slower delivery. • Economic and ecological incentives significantly increase willingness to wait. • Responses vary by age, gender, environmental awareness and urgency of orders. • Practical recommendations to expand the range of delivery options. [ABSTRACT FROM AUTHOR]

This paper forecasts the growth of freight transport emissions in India's trucking sector until 2050. We use the ARIMAX time series model to project the commercial vehicle population under various economic growth scenarios. CO 2 emissions are estimated using emission factors, distance traveled, and the projected commercial vehicle population. We use the validated forecasting model to investigate how emissions can be curbed through vehicle scrappage policies or fleet electrification to realign with the 2015 Paris Agreement's targets. Compared to the business-as-usual (BAU) scenario, 10-year and 15-year vehicle scrappage policies are estimated to reduce freight emissions by 6–11% and 1–2%, respectively. Fleet electrification has more pronounced effects as it results in a 35% and 70% reduction in carbon emissions for heavy and light goods vehicles in 2050, respectively, compared to the BAU scenario. These findings provide crucial insights for devising policies to mitigate greenhouse gas emissions in India's trucking industry. [ABSTRACT FROM AUTHOR]

• Application of solar energy according to land use/land cover map. • Electrification of transportation sectors based on local renewable energies. • Comparison of conversion and storage efficiencies of different energy forms in transportation. • Reducing transportation and urban environmental impacts. • Multi-criteria decision-making of sustainable transportation based on sustainable development pillars. The main aim of this paper is the decarbonization of the transportation sector in Tabriz City regarding sustainable development aims and beyond-2-degrees-scenario by focusing on electric vehicles, as well as on appropriate infrastructures. Quantitative and simulation research methods are used to analysis of total energy, exergy, and losses analysis according to different resources and vehicles. Next, the solar potential of the city is simulated using the Grasshopper plug-in-Rhino simulator and PVsyst software. A LULC analysis has been done using ArcMap 10.8. With renewable electrification, energy consumption will plunge from 15.5 TWh input-energy content of different carbon-based resources to 3.7 TWh with 0.17 MtonCO 2 /year instead of 2.13 MtonCO 2 /year emissions. In this paper, the overall system efficiency of electric vehicles is around 55% which is significantly higher than internal combustion engines. Fully electrification of the transportation systems based on renewable resources mitigates CO 2 emissions of internal combustion engines 15 times, besides reducing the emissionsa variety of harmful pollutants. In terms of multi-criteria decision-making, the technique for order of preference by similarity to the ideal solution was used to rank 50 popular vehicles according to interconnected sustainable development criteria. This paper highlights that conventional internal combustion engines can be replaced by electric vehicles by applying combination of appropriate taxes, tariffs, and incentives. [ABSTRACT FROM AUTHOR]

Heavy-Duty Vehicles (HDVs) pose a significant challenge in meeting emissions reduction targets. However, studies on estimating emissions from Irish HDV fleet are rare. This paper estimates fuel consumption and CO 2 emissions from tractor-trailers that occupy nearly half of Ireland's HDV fleet using the European Commission recommended VECTO tool. To improve the estimation accuracy, driving cycles specific to Irish road conditions were developed utilising real naturalistic driving data from trucks. The Irish driving cycles significantly differ from the VECTO inbuilt driving cycles in percentage time spent in different gears, fuel consumption, and CO 2 emissions. CO 2 emissions estimated with Irish driving cycles range from 733 to 1961 g/km, while with VECTO driving cycles, the values ranged from 728 to 1865 g/km. Further, the study evaluated the sensitivity towards payload, road gradient, and idling percentages. The study insights would provide an essential evidence base for policymakers in Ireland. [Display omitted] • Developed Irish urban, regional, and freeway driving cycles. • Employed the VECTO tool to assess CO 2 emissions from Irish heavy-duty vehicle fleet. • Focused on tractor-trailers with a major share in the Irish fleet. • Evaluated the effect of idling, gradient, and payload on CO 2 emissions. • Fuel consumption is underestimated by up to 7.1% when the road gradient is ignored. [ABSTRACT FROM AUTHOR]

• The paper investigates the impact of highway extension on new building construction. • The investigation focuses on a project that aims to limit land use change. • The infrastructure increases the probability of construction on surrounding parcels. • The impact is spatially concentrated around the access ramp and along the highway. Despite its impact on both sprawl and carbon emissions, developing or expanding highway infrastructure remains the object of strong political support. Highway access provides important advantages for firms and households, generating powerful incentives to develop new built areas through the conversion of vacant land. Based on the case study of the expansion of Highway 30 on Montréal's South Shore region between 2000 and 2019, this paper investigates how new highway infrastructure impacts the construction of new industrial and commercial buildings on individual parcels. Using a panel dataset, an event study model is developed to estimate the impact of the proximity to highway access ramps on the probability of construction. Results show that highway infrastructure increases the probability of construction of new industrial and commercial buildings, even if public authorities aim to limit such possibilities by legal constraints and laws. [ABSTRACT FROM AUTHOR]

[Display omitted] To achieve carbon neutrality, it is urgent to quantify carbon emissions to support policy deployment. Based on life cycle assessment, this paper proposed calculation method for carbon emissions from road infrastructure in a Demonstration Zone, China. Based on scenario analysis, this paper quantified the carbon emissions currently and analyzed the trend and characteristics of carbon emissions of road infrastructure from 2020 to 2060 through 4 scenarios. The results show the carbon emissions fluctuate between 20 kt and 540 kt CO 2 from 2013 to 2019 and increase significantly in 2014 due to the surge in road mileage. In the first three scenarios, the carbon emissions show an increasing trend after 2030, with annual growth rates of 1.12%, 0.57%, and 0.27% respectively. However, in the optimal scenario, the peak year of carbon emissions is 2024, with the peak emissions of 649.333 kt CO 2 and an increase of 245% over the base year. [ABSTRACT FROM AUTHOR]

Greenhouse gas emissions lead to climate change, subjecting the maritime environment to severe threats. In response, globally, states and organizations are taking actions to decarbonize. In this context, this paper builds an evolutionary game analysis involving the government and shipping company under a governance framework with IMO, from a perspective of economic regulations, and explores how to establish a proper shipping decarbonization mechanism and implementation plans in the process of dynamic evolution. Based on a system dynamics simulation model, we analyzed how the cap-and-trade policy system, tax-and-subsidy policy system, and cooperative policy system perform in terms of shipping decarbonization and the role of IMO in shipping decarbonization. Our research proves that the cooperative system is more efficient and stable in decarbonization than singular economic regulations; static and dynamic implementation plans should be coordinated in different stages; and finally, IMO plays an active role in multi-agent coordinated controls. [ABSTRACT FROM AUTHOR]

Freight transport decarbonization is challenging due to the slow implementation of policies to meet climate goals. This paper analyzes the dynamics of the implementation of freight decarbonization measures. A System Dynamics model was developed and applied to the Brazilian freight system to simulate the use of more sustainable modes and means of transport, including electrification, increased use of biofuels, acceleration of fleet renewal, and modal shift. Significant emission reductions are found in the scenarios combining a shift to alternative modes and a rapid phase-out of diesel vehicles. Even so, the Brazilian freight sector's emission budgets towards limiting global warming to 1.5 °C and 2 °C will be depleted during the current and next decade, respectively. An absolute reduction of carbon emissions before 2050 seems unlikely. Besides confirming the need to study the dynamics of the freight system, the findings corroborate the urgency for stronger actions on freight decarbonization. [ABSTRACT FROM AUTHOR]

This paper examines individual preferences for a reduction of life-cycle CO 2 emissions in vehicle purchase decisions. The empirical analysis is based on data from a stated choice experiment among citizens in Germany that refers to decisions between three types of electric vehicles and one conventional vehicle that are characterized by several attributes. With respect to CO 2 emissions, we specifically examine emissions in vehicle production besides the commonly considered emissions in vehicle use. Our econometric analysis reveals a strong stated preference for the reduction of both components of life-cycle CO 2 emissions. Furthermore, we find that conventional vehicles are significantly preferred over electric vehicles. Surprisingly, environmental attitudes, i.e. environmental awareness and ecological policy identification, have no significant effects on the reduction of CO 2 emissions. Instead, citizens with a strong environmental identity rather tend to avoid the purchase of conventional vehicles. We discuss several practical policy implications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Reviewed + 200 research papers related to geopolymer concrete. • Utilization of industrial waste and recycled aggregates in geopolymer concrete is focused. • 12 M + molarity of sodium hydroxide is efficient for geopolymer based concrete pavements. • Geopolymer based rigid pavements ensure a cleaner environment. After industrial sector, construction sector utilizes significant quantity of natural raw materials and energy sources. Construction sector waste needs dumping spaces whereas the industrial sector waste like, fly ash and coal bottom ash poses health hazards as they contaminate water, air and soil. Pozzolanic concrete utilizes industrial waste by substituting a portion of cement (<60 %) and offers better durability with similar mechanical properties to normal concrete. Geopolymer concrete, a durable and high-strength concrete, has been devised to fully substitute cement with industrial wastes. This study reviews the requisites of geopolymer concrete to perform like pavement quality concrete while utilizing maximum quantity of wastes in both the binder and aggregate phase. This paper concludes that geopolymer concrete can be used in pavements even with more than 50 % virgin aggregate substitution with recycled aggregates. Further, the mix should be enriched with ground granulated blast furnace slag with sodium hydroxide molarity within 12–16. [ABSTRACT FROM AUTHOR]

Publicly developed logistics parks (PDLPs) have been considered one of the measures in urban logistics policies to reduce carbon emissions. In response, this paper draws on the "pollution transfer" hypothesis, constructs a carbon emission analysis framework for PDLPs, and uses spatial econometric methods to explore their carbon emission effects. The findings suggest that from a global perspective, PDLPs can lead to the emergence of "pollution havens" in the suburban and exurban areas while relieving the carbon emission burden in the urban core. Secondly, PDLPs can further contribute to forming "pollution havens" by promoting logistic re-agglomeration, and the "innovation compensation" effect of PDLPs is not significant. Finally, the carbon emission effects of PDLPs are spatiotemporally heterogeneous. A carbon reduction effect is noted when the logistic re-agglomeration in the location of PDLPs is higher, and an "innovation compensation" effect is also produced when the technological innovation is higher. [ABSTRACT FROM AUTHOR]

The increasing of carbon emissions due to traffic congestion in urban centers has been plaguing city managers. Park-and-Ride system are considered as important solutions to reduce urban carbon emissions. However, research on parking reservation on park-and-ride systems is still insufficient. Therefore, this paper explores the impact of parking reservation mechanisms on park-and-ride systems. A multi-modal agent-based network model is constructed to simulate the park-and-ride behavior, different parking reservation strategies are assessed and optimized which aim to minimize carbon emissions. Taking the Suzhou Guanqian Street Commercial District, China as the numerical example, we analyzed the impact of parking space allocation on carbon emissions. When parking spaces are reserved in proportion to demand, emissions decrease until a 70% reservation ratio. Beyond this threshold, emissions increase. Employing Genetic Algorithm (G.A.) to optimize the allocation of reserved parking spaces in each parking lot can further reduce carbon emissions. [ABSTRACT FROM AUTHOR]

• This paper provides a review of existing literature on CO 2 emission implications of HSR projects due to Modal Interactions. • We consider the interactions of HSR with other transport modes, including air, road, and conventional rail. • We conceptually classify the related studies into three levels. • Most papers on the HSR-induced modal shift and CO 2 emissions focus on air transport. • We identify future research opportunities after the review. This paper reviews existing literature on the CO2 emissions implications of high-speed rail (HSR) projects due to its interactions with air, road, and ordinary-speed rail. We conceptually classify the studies into three levels, with the first focusing on the emission comparison between HSR and the other modes, the second on the emission implication due to HSR-induced traffic reallocation, and the third on the life cycle assessment (LCA). We find that the literature is still in a relatively premature state. We also identify future research opportunities, including: i) to carry out a more detailed and comprehensive analysis regarding how HSR affects cargo operations of other transport modes and the corresponding CO 2 emission implications, ii) to further develop the game-theoretical models to be applied to estimate a fuller picture of modal splits and the corresponding CO 2 emission impacts, and iii) to apply LCA by considering the avoided life-cycle emissions associated with infrastructure and vehicles due to traffic diversion and the intricacies of modal interactions. [ABSTRACT FROM AUTHOR]

This paper inspects the environmental Kuznets curve (EKC) in various transport sectors in 13 European Union (EU) countries. The study uses the augmented mean group estimator (AMG) estimator to examine the relationships between carbon (CO 2) emissions, income, and energy consumption of four transport modes, such as road, maritime, rail, and air, between 1995 and 2019. The outcomes illustrate that the EKC hypothesis is valid for six countries in air transport, four in maritime transport, three in rail transport, and six in road transport. In addition, the findings indicate that fossil fuels significantly increase CO 2 emissions from transportation modes. In light of the study's findings, EU countries should improve energy efficiency in the transportation sector to become carbon neutral by 2050. In order to ensure an environmental balance between transport modes, policymakers should support innovative activities to increase renewable fuel consumption. [ABSTRACT FROM AUTHOR]

In view of the climate emergency, it is necessary to model and forecast road transport emissions for implementing more effective climate policy. This paper fills an important research gap by quantifying the challenges, barriers and remedies of achieving road transport emission reduction and air quality improvement in developing countries. It contributes to the debate on top-down and bottom-up approaches to reconcile carbon and other transport related emissions. China and India are chosen as case studies. Using various official statistics and proxy variables, we estimate and compare the road transport carbon emissions of the two countries systematically from 2009 to 2020. Insights from detailed mode-specific estimations of the bottom-up approach are valuable for targeted policies and measures. An analysis of the major components of road transport carbon emissions points to strategies of promoting electric vehicles, reducing transport demand, accelerating modal shift to low-carbon modes, and cleaner electricity to achieve climate policy. [ABSTRACT FROM AUTHOR]

The development of BEVs (battery electric vehicles) can significantly mitigate the dependence on fossil fuels and reduce carbon emissions. To advance the development of BEVs, China is adjusting the subsidy and dual-credit policies. This paper addresses these two issues to help policymakers determine effective policies. Through the simulation with a system dynamics model that incorporates the government, automakers, infrastructure operators, and consumers, we find that (1) reducing the overall level of subsidies has a minor impact on the development of BEVs in the long term; (2) subsiding the construction of infrastructure, especially battery swapping stations, will produce better effects than others; (3) the proposed carbon quota mechanism, which is in line with the unified carbon market, is more conducive to the diffusion of BEVs and carbon reduction than the dual-credit policy. Our MLP-SD (multi-level perspective system dynamics) model broadens the analytical perspective of the technology transition in the automobile industry. [ABSTRACT FROM AUTHOR]

The EU 'Fit for 55' package proposes the adoption of various legislative tools to eliminate shipping CO 2 emissions, among which are the inclusion of shipping in the EU Emissions Trading System (EU ETS) and the FuelEU Maritime Initiative. This paper analyses the latter by utilising the EU's Monitoring, Reporting, Verification (MRV) database to evaluate the fuel types used, fuel consumption and CO 2 emissions of ships operating within the European Economic Area (EEA) for 2020, the Initiative's baseline. Forecasts of potential future pathways for alternative fuel deployment are then developed that could be used to achieve compliance with the limits set by the FuelEU Maritime Initiative. The results of this study provide significant input to maritime stakeholders and policy-makers on the potential impact of the Initiative for the uptake of clean marine fuels and the contribution of the maritime sector to a climate neutral Europe by 2050. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to revisit speed optimization and speed reduction models for liner shipping in a multi/flexible fuel context with regards to the current ongoing speed limit debate at the International Maritime Organization (IMO). The focus is mainly on analyzing the influence of a maximum average speed limit on the optimal speeds, carbon intensity and emissions in conjunction with fleet deployment for dual fuel (DF) Neopanamax container vessels utilizing liquefied natural gas (LNG). [ABSTRACT FROM AUTHOR]

The innovations in battery technologies facilitate worldwide bus electrification, which can conserve energy and reduce emissions. This paper studies the long-term bus electrification that simultaneously optimizes the charging infrastructure deployment and bus fleet transition. The seasonal differences associated with battery capacities, bus lines, and bus timetables are considered. The studied problem is modeled as a mixed-integer linear programming formulation, in which the detailed charging schedules are determined to give the charging location and charging time. The objective minimizes both the cost and emissions. The proposed formulation is tested on a real-world case study. The computational results indicate that replacing DPBs with BEBs can save 17.8% of total cost and decrease 39.3% of carbon dioxide emission. Compared with designing a plan for each period separately, implementing long-term bus electrification can save 13.5% of total cost and 21.7% of operational cost. Moreover, the benefits of implementing long-term bus electrification are more remarkable when the planning horizon is longer. [ABSTRACT FROM AUTHOR]

• The top 5% of car users travel nearly 27,500 miles (4.8 times the average) and emit 5742 kg CO 2 annually (5.7 times the average). • The top 20% of car users in England travel 16,740 miles and emit 3200 kg CO 2 annually. • Male, high-income professionals and large car owners are more likely to record higher mileage. • Rationing the top 5% of car users would reduce emissions by 6.9% whilst rationing the top 20% would lead to reductions of 26%. • Rationing high CO2 emitters directly is more effective than rationing car mileage. This paper measures 'excess' car travel for its role in decarbonisation. On average, each English adult travels around 5,680 miles a year and emits 1,006 kg of CO 2. However, the top 5% 'excess' car users travel 4.8 times and emit 5.7 times the national average. Four binary logistic regression analyses were used to model the probability that people with specified characteristics belong to the 'excess' mileage and emitter groups. Results indicated that gender, employment and socio-economic status, household income (higher quintiles), company car availability, residential location and local population density were highly significant correlates of this 'excess' travel mileage. Multiple car ownership, business travel by car, multiple international flight frequencies and ownership of larger and diesel cars were positively associated with excess travel and emissions. A mileage rationing scheme targeting the top 20% users can cut emissions substantially (by 26%) compared to targeting 'excess' (top 5%) users only. [ABSTRACT FROM AUTHOR]

This paper examines the impact of geographical location on the energy consumption of double deck battery electric buses operating in four UK cities. By considering seasonal variation in ambient temperature and an assumed battery degradation process, the implications on operational cost and carbon emissions were investigated. Using a MATLAB/Simulink model the total energy demand of a vehicle operating on the UKBC was simulated. Energy consumption was combined with hourly seasonal averages of carbon intensity (gCO 2 /kWh) and wholesale electricity costs (£) to assess charging at different times of the day and year. At the beginning of life, the range could decrease by up to 17.3% due to heating load requirements. From beginning of life to end of life, range was predicted to decrease by up to 26%. Whilst the average operational costs are relatively consistent across the four regions, the average carbon emissions can be five times higher depending on location. [ABSTRACT FROM AUTHOR]

• E-scooters' car-trip substitution potential for e-scooters estimated on basis of based on German mobility data. • 13 % of daily car trips or 2 % of vehicle-kilometers traveled suitable for replacement. • Calculation of daily potential greenhouse gas reduction through by switching to e-scooters. • Maximum savings of 1.2% of transportation GHG achievable if replacing gasoline cars. • Savings highly dependent on use case; potentially negative for BEV-replacement potentially negative. This paper explores which trips currently made in Germany by personal motorized transportation could be replaced by e-scooters and what effect this would have on greenhouse gas emissions. This potential for substitution is estimated on the basis of data from the national household travel survey in Germany. Our analysis shows that 13% of the daily car trips, corresponding to 2% of the car kilometers in Germany, are suitable for replacement. Based on these results, we show that saving potentials of greenhouse gas emissions are heavily dependent on the general conditions of the specific use case (e.g. e-scooter lifetime) and the type of vehicle replaced. At best, a saving potential of about 5.8 kt of CO 2eq per day could be achieved when trips with conventional cars are replaced by e-scooter driving. However, if battery electric cars are replaced, an increase in emissions may even occur under certain conditions. [ABSTRACT FROM AUTHOR]

The pressure on shipping to reduce its carbon footprint is increasing. Various measures are being proposed at the International Maritime Organization (IMO), including Market-Based Measures (MBMs). This paper investigates the potential of a bunker levy in achieving short-term CO 2 emissions reductions. The analysis focuses on the tanker market and uses data from the latest IMO GHG studies and a variety of other sources. The connection between fuel prices and freight rates on the one hand and vessel speeds on the other is investigated for the period 2010–2018. A model to find a tanker's optimal laden and ballast speeds is also developed and applied to a variety of scenarios. Results show that a bunker levy, depending on the scenario, can lead to short-term CO 2 emissions reductions of up to 43%. Policy implications are also discussed, particularly vis-à-vis recent IMO and European Union (EU) action on MBMs. • Some properties of the tanker speed optimization problem are investigated. • We use data from GHG studies and several other sources to compute CO 2 emissions. • The link between speed and the ratio of spot rate by fuel price is investigated. • A bunker levy can reduce CO 2 emissions from tankers up to 43% in the short-term. • The IMO 50% GHG reduction target is unreachable via slow steaming induced by a levy. [ABSTRACT FROM AUTHOR]

This paper develops an infrastructure-enabled eco-approach specifically for transit systems, where a two-stage simulation approach is proposed to include the impact of bus stops, and can further quantify the effects of infrastructure-enabled eco-approach on transit operating and service. The developed system is then embedded into a well-developed simulation environment, i.e., Simulation of Urban Mobility (SUMO), and a series of real-world-based cases are designed to compare the proposed system with traditional method and non-control case at segment-, line-, and network-level service respectively. Results reveal that the proposed method outperforms the traditional eco approach and can significantly improve the energy efficiency and reduce CO 2 emission by up to 54.33%, where the environmental benefits are more clearly seen when more transit services are involved. In particular, it has the capability of marginalizing the speed fluctuations around the bus stop. [ABSTRACT FROM AUTHOR]

Designing low-construction-emission cross-sections of mountainous highway alignments is challenging. To address this issue, this paper develops a framework of cross-section optimization for highway alignment (COHA) to minimize the construction costs and emissions of the mountainous highway. First, COHA enumerates the earthwork costs of all possible highway cross-section locations in each cross-section profile. Second, we classify cross-sections into two categories, sensitive and nonsensitive cross-sections, with stochastic dominance (SD) theory and a complete ranking method. Third, to obtain the final optimized highway alignment, the initial alignment determined by optimal cross-sections is fitted by the weighted least square method with two dimensions. Finally, this methodology is applied to a real-world case study in a mountainous region, and the results verify that COHA can automatically optimize highway alignment, decreasing carbon dioxide emissions and land use by 3.6 % and 3.1 %, respectively, compared with manual work. [ABSTRACT FROM AUTHOR]

• We identify the relationship between bike sharing and public transit (PT). • We estimate the environmental impacts of bikeshare as it also substitutes PT. • 27.9% of bikeshare trips substitute buses and 8.1% substitute subways. • Bikeshare has significant environmental benefits by replacing other modes. • Environmental benefits are overestimated if not considering the substitution for PT. Bike sharing has the potential to benefit the environment with less energy consumption and CO 2 emissions. Most previous studies on this topic assumed that bikeshare trips mainly substitute cars. However, bikeshare also replaces ecologically friendly transportation modes like public transit (PT). Therefore, it is vital to examine bikeshare's modal shift from PT to fully assess its environmental impacts. This paper examines the bikeshare and PT relationships in Chengdu,and environmental effects of bike sharing under two cases based on this relationship. The first case only considers the substitution of bikeshare for car and walking, and 19,964.31 L of fuel and 4125.13 kg of CO 2 can be saved; while the second case also considers its substitution for buses and subways, and 13,198.68 L of fuel and 2564.31 kg of CO 2 can be saved. Results indicate that the environmental benefits of bike sharing may be overestimated if not considering its substitution for PT. [ABSTRACT FROM AUTHOR]

Low-carbon travel for rural residents in China is of great significance for reducing CO 2 emissions and achieving the "dual carbon goals". This paper uses system dynamics modeling and case analysis to explore the realization path of low-carbon travel in rural China, establishes a complex system dynamics model of low-carbon rural travel in China. By running multi-scenario simulations, the characteristics of rural residents' travel and the trend of CO 2 emissions in China are found. Through the case study, it is found that the built environment, low-carbon travel policy, rural residents' travel preference and travel cost are the important factors affecting rural low-carbon travel. New energy policy can effectively reduce rural travel CO 2 emissions. However, an excessively large increase in rural low-carbon public transport would reduce marginal benefits. The government should choose the right policy intensity according to the economic and fiscal situation. [ABSTRACT FROM AUTHOR]

• Sufficiency is an essential pillar of sustainability. • Individual mobility budgets carbon reduction goals more comprehensible. • The perceived fairness is crucial for the distribution individual mobility budgets. • Individual mobility budgets can serve as an indicator for transport justice. Transport justice has two essential dimensions: (1) compensating for inequalities in access to mobility, and (2) mitigating the disproportionately burdensome negative consequences of transport. In light of the urgently needed action regarding climate change especially in the transport sector, measures reducing carbon emissions to mitigate the impact are inevitable. However, policy measures for reaching climate targets should avoid increasing unequal mobility chances. Therefore, there is a need for concepts striving to mitigate both climate impacts and transport injustice. The paper addresses the potential of introducing individual mobility budgets to achieve transport-related climate goals while reducing inequalities in mobility. The concept proposed in this contribution is based on a combination of qualitative and quantitative impact assessment methods including a stakeholder involvement process and transport modelling based on different data sources. The results provide policy recommendations as well as further research requirements, which are already partly addressed iin follow-up projects. [ABSTRACT FROM AUTHOR]

• We evaluate decarbonization of passenger transportation in Rio de Janeiro, Brazil. • Public transport and carpooled shared mobility rise system capacity and reduces CO 2. • Biofuels reduce CO 2 emissions at no increased system cost. • CO 2 price is the most effective decarbonization policy, but it is costlier. • Increased renewable electricity and electrification of the fleet reduce the most CO 2. This paper applies an energy systems model to evaluate how shared mobility (ride-hailing and shared autonomous vehicles), public buses, alternative energy sources (electricity and biofuels) and carbon pricing contribute to reduce passenger vehicles CO 2 emissions in Rio de Janeiro state, Brazil, from 2016 to 2050. Public buses and carpooled shared mobility increase system capacity, resulting in lower vehicle ownership, energy demand and CO 2 emissions, as well as savings per ton of CO 2 abated (from $3 to $4186). Biofuels reduce CO 2 emissions at no increased system cost, while carbon pricing is the most effective policy to reduce CO 2 emissions, but it is costlier than the alternatives and results in greater private vehicle use (up to 260%) if the expansion of zero-carbon public transportation remains limited due to technology adoption. The policy that reduces the most emissions (by 84%) combines the expansion of renewable electricity generation and implementation of a CO 2 price. [ABSTRACT FROM AUTHOR]

• Estimates energy usage and emissions of domestic intercity air travel in the U.S. • Analyzes emissions dynamics of intercity air travel via supply and demand factors. • Emissions per passenger have declined by nearly 40% over the last two decades. • Route frequency, fleet efficiency and deployment are leading contributing factors. Domestic intercity air travel accounts for nearly 80% of all air travel in the U.S. As low-cost airlines and economic growth have increased the affordability of intercity air travel, the benefits to travelers and cities are touted by most. Yet, an accounting of the energy consumption and emissions from domestic intercity air travel is rarely discussed. This paper fills that gap and provides an analysis of the trends in fuel consumption and emissions by intercity air travel as well as an analysis of the contributing factors to these emissions. Using flight tracking and carrier data, emissions per passenger are found to have declined by 40% over the past two decades while total emissions have increased by 10% over the past 8 years. A decomposition analysis of the market factors highlights changes in route frequency, fleet deployment, and fleet efficiency as the leading factors contributing to the decline of intercity emissions. [ABSTRACT FROM AUTHOR]