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• Climate change concern can contribute to reduced car use and sustainable mobility. • Those worried about climate change were more willing to live without a car. • Relationship between climate change concern and car use differs based on type of car. • Worry about climate change was strongly related to lower use of a conventional car. • Worry about climate change was unrelated to the use of an electric car. Climate change concern has been linked to climate-friendly behavior, but little is known on whether and how it may promote sustainable mobility. This paper investigates how worry about climate change relates to attitudes and intentions towards the car as well as the actual use of conventional and electric cars in Oslo and Viken in Norway. Findings indicate a relationship between worry about climate change and reduced car use, mediated by mode preferences and willingness to live car-free. Those concerned about climate change were less likely to commute by a conventional car and used conventional cars less both on weekdays and weekends. Worry about climate change was also related to living in a denser neighborhood, preference for travel modes other than the car, and willingness to live car-free. Raising greater awareness of climate change could contribute to climate change mitigation by promoting car-reduced or car-free lifestyles and sustainable mobility. [ABSTRACT FROM AUTHOR]

• Insights from transportation research used to improve comprehensive ESOM. • Capturing underlying heterogeneities by increasing contextual model resolution. • The setup underpins importance of tailoring climate strategies to specific settings. • Behavioural shifts have different implications depending on the contextual setting. • Failing to address key cost barriers delays car fleet electrification by five years. Meeting ambitious climate targets requires deep cuts in emissions from passenger transportation. Many studies point to electrification and behavioural shifts as key measures. Spatial, demographic, economic, and transport-sector-related factors shape the opportunities and preferences for change, thus setting the direction and pace of the transition. These factors typically differ between urban, suburban and low-population-density settings, a fact that is generally overlooked in comprehensive energy system optimisation models (ESOM). This study introduces a novel contextual representation of passenger transportation within a national ESOM (TIMES-Sweden). When testing the new approach, different cost barriers to electrification are found across various settings, signalling a need for different policy responses. Further, opportunities for – and impact from – shifts in travel behaviours vary significantly across settings. These results highlight the need for climate change mitigation strategies in passenger transportation which are better tailored to specific contexts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Active mobility (AM) contributes to the mitigation of climate change. • The study offers a methodology to measure the street use environmental impacts. • Refurbishment return environmental rates do not exceed seven months. • Sustainable transportation requires strategies: AM, carpooling, and mass transport. • Measuring the impacts of street use could generate sustainable interventions. Active mobility (AM) is a fundamental part of a sustainable mobility system that generates environmental and social advantages; however, its use and operation are understudied using quantitative tools such as life cycle assessment (LCA), especially in the Latin American context. This study aimed to analyze the use stage of a street located in Northern Mexico. Two real scenarios were compared, one conventional (CO-SC-2020) and another sustainable (SU-SC-2022), which incorporated the concept of "complete streets" through a bicycle lane and the improvement of pedestrian spaces. Available data from the "Vía Libre" project and PIMUS, as well as SIMAPRO and Ecoinvent, were used for the LCA. The results indicated that the environmental impacts derived from transportation could be reduced through strategies such as active mobility (6.55%) and carpooling (77%), favoring the conversion of cities that consider the automobile as the guiding axis to more sustainable, inclusive, and safe cities. [ABSTRACT FROM AUTHOR]

The environmental impact of battery electric vehicles (BEVs), which are an integral part of climate change mitigation measures, depends on charging strategies, such as uncontrolled charging, controlled charging (V1G), and discharging (V2G). However, the impact is unclear because power system operation involves the cost of carbon dioxide (CO 2) emissions and flexibility requirements for imbalances caused by renewable energies. To clarify the robustness of the environmental impact of BEVs, we assessed the interactions between CO 2 prices and flexibility requirements in Japan in 2030 using a production cost model. The results showed that uncontrolled charging increases CO 2 emissions, whereas V1G or V2G reduces them. Further, the impact of BEVs was non-monotonic with respect to CO 2 prices, implying that policymakers should carefully evaluate CO 2 prices to achieve decarbonization as BEVs do not always reduce CO 2 emissions. This study provides useful insights for policymakers in countries with low-cost, inflexible, and high-emission power plants. [ABSTRACT FROM AUTHOR]

Transportation electrification is a promising emerging technology for mitigating the impacts of climate change. However, it provides more challenges to mobility management during disruptive events. Extensive research has been conducted to describe the consequences of transportation electrification and disruptive events, each in silos. A pivotal question nowadays is, "What are the requirements of Electric Vehicles' (EVs) mobility during disruptive events?". Thus, this study aims to critically review previous works addressing the interrelationship between transportation electrification and critical infrastructure during disruptive events. The findings of this study have significant implications for preserving the resilience of the transportation network and the power grid during disruptive events, embracing the role of EVs in disaster management planning, and promoting the rollout of e-mobility to achieve climate action targets. [ABSTRACT FROM AUTHOR]

• Below 200 g CO 2 eq./kWh, chargeable bus emissions lower than HVO-biodiesel hybrids. • Above 750 g CO 2 eq./kWh, diesel hybrids preferable to plug-in/all-electric buses. • Excluding operation, chassis, frame and body dominate load in all buses. • All-electric buses best for reducing local air pollution and regional impact. This study explores life cycle environmental impacts of city buses, depending on the: (1) degree of electrification; (2) electricity supply mix, for chargeable options; and (3) choice of diesel or hydrogenated vegetable oil (HVO), a biodiesel, for options with combustion engine. It is a case study, which uses industry data to investigate the impact on climate change, a key driver for electrification, and a wider set of impacts, for average operation in Sweden, the European Union and the United States of America. The results show that non-chargeable hybrid electric vehicles provide clear climate change mitigation potential compared to conventional buses, regardless of the available fuel being diesel or HVO. When fueling with HVO, plug-in hybrid and all-electric buses provide further benefits for grid intensities below 200 g CO 2 eq./kWh. For diesel, the all-electric option is preferable up to 750 g CO 2 eq./kWh. This is the case despite batteries and other electric powertrain parts causing an increase of CO 2 emissions from vehicle production. However, material processing to make common parts, i.e. chassis, frame and body, dominates the production load for all models. Consequently, city buses differ from passenger cars, where the battery packs play a larger role. In regard to other airborne pollutants, the all-electric bus has the best potential to reduce impacts overall, but the results depend on the amount of fossil fuels and combustion processes in the electricity production. For toxic emissions and resource use, the extraction of metals and fossil fuels calls for attention. [ABSTRACT FROM AUTHOR]

• This paper tests the relationship between multimodality and CO 2 emissions. • Multimodal trips are less polluting than unimodal trips, if controlled for distance. • More-multimodal persons have lower emissions, notably if controlled for distance. • Multimodality is only weakly associated with CO 2 emissions. • Trip distance contributes more to CO 2 emissions than the level of multimodality. Encouraging multimodality as a tool to reduce exclusive car use is seen as a key ingredient of transport policies aimed at reducing greenhouse gases emissions, such as CO 2. These policies are based on the assumption that increasing multimodality will contribute to a reduction in emissions. Yet, hardly any scientific attention has been paid to the empirical relationship between multimodality and CO 2 emissions. This article addresses this unexplored question at both the individual and trip level using the English National Travel Survey. We find that the level of multimodality is only weakly associated with CO 2 emissions. It is only when controlling for levels of travel activity (trip frequency, total distance travelled) that a moderate association in the expected direction is observed (i.e. that higher levels of multimodality correspond with lower CO 2 emissions). This suggests that greater levels of travel activity among multimodals tend to offset the benefits derived from their more diverse modal choices. Similar patterns emerge from the trip-level analyses: higher emissions are found for (the typically longer) multimodal trips compared to unimodal trips, even when the only mode used is the car. However, for trips over similar distances, multimodal trips do have lower emissions. While there is merit in encouraging greater multimodality, this can hardly be the only or primary goal of climate mitigation policies in the transport sector. More attention needs to be paid to the key role of high levels of travel activity, and how these could be reduced. [ABSTRACT FROM AUTHOR]

• Highlights factors that affect life cycle GHG emissions of light-duty vehicles. • Provides a typology of these factors. • Performs an in-depth review of 14 popular integrated energy models. • Highlights the importance of considering certain factors for policy analysis. • Identifies potential modeling improvements regarding the representation of vehicles. Light-duty vehicles (LDVs) are responsible for more than one tenth of global energy use and CO 2 emissions and are therefore an important focus in pollution mitigation efforts. Integrated energy models (IEMs) are frequently used to explore cost-optimal climate change mitigation measures for energy supply and demand sectors, such as LDVs. Options include fuel and powertrain switching through efficiency standards, taxation, and technology mandates. This review provides an overview on how LDVs are modeled in 14 popular IEMs. We find that the representation of mitigation options can be enhanced by linking emissions and physical outputs from industry, agriculture, and energy conversion directly to the vehicle life cycle and by more carefully reflecting important factors that influence LDV life cycle emissions. This would allow for a more complete internalization of emissions in the technology mix optimization procedure of IEMs. The results highlight a range of mitigation options currently not considered in most integrated models, such as reducing embodied emissions in infrastructure and vehicle production, reducing methane leakage, or switching to less carbon intensive crude oil grades. [ABSTRACT FROM AUTHOR]

• Develop an energy system optimization model with shared autonomous vehicles (SAVs). • Analyze ten scenarios to explore the economic and climate change impacts of SAVs. • SAVs lower costs and carbon emissions, even if they induce significant additional VMT. • This is primarily because a transition to SAVs accelerates vehicle electrification. • Synchronizing electric SAV charging with renewable power output has large benefits. The climate change impacts of the anticipated growth in shared autonomous vehicles (SAVs) are highly uncertain due to competing mechanisms whose magnitudes are difficult to estimate. On the one hand, SAVs could reduce greenhouse gas emissions by driving more efficiently, avoiding traffic congestion, accelerating adoption of alternative fuel vehicles, and charging in alignment with renewable electricity generation. On the other hand, SAVs could induce more vehicle miles traveled (VMT) by lowering the time cost of travel and allowing non-drivers to travel more by car. In this study, we develop an energy system optimization model that integrates the electricity and transport sectors, computes endogenous technology adoption, and distinguishes SAVs from privately owned vehicles (POVs) to explore the contributions of SAVs to climate change mitigation. Our results show that widespread SAV adoption lowers costs and emissions, and that these desirable outcomes remain true even if SAVs induce double the VMT of the POVs they replace. SAVs dramatically accelerate the market penetration of electric vehicles. The environmental and economic benefits of this electrification trend are larger if electric SAV charging can be optimally aligned with renewable electricity generation. Especially in the short to medium term, SAV adoption can be a more impactful lever than a carbon tax for decarbonizing vehicle travel. [ABSTRACT FROM AUTHOR]

[Display omitted] Major efforts are still needed to decarbonize passenger transport. To do so, a combination of improved technologies, a shift towards public transport, cycling and walking and the avoidance of trips is crucial. However, to ensure successful implementation, we need to better understand how these strategies affect the overall costs to society. Therefore, we assess the social costs of a decarbonized ground-based passenger transport system in 2040, covering vehicle costs, costs for externalities and travel time costs across travel modes. Our results show that social costs decline with the introduction of decarbonization strategies. Specific effects include a reduction of vehicle costs and external costs, a rise in external benefits due to positive health effects of active mobility that overcompensate remaining external costs, and possibly increased travel time costs. [ABSTRACT FROM AUTHOR]

Maritime emission regulations set limits for SOx and NOx emissions for health and environmental reasons, and for CO 2, through the Energy Efficiency Design Index (EEDI), with the general aim of mitigating global warming. EEDI verification is performed at the vessel's design speed and design loads, under calm-water conditions. This, although calm seas are the exception in shipping, and that even with calm-water conditions, ships usually operate at lower speeds than their design speed. A major challenge, if greenhouse gases (GHG) reduction targets are to be met through the EEDI, will be to identify EEDI-compliant solutions that reduce energy consumption and GHG emissions under realistic operational conditions, from lying idle at berth in port to when full power is required in critical situations at sea. In view of all the above, we use the Aframax tanker class to illustrate how such an assessment can be performed, and to display the differences in costs and benefits of options, all of which meet the requirements of the EEDI. [ABSTRACT FROM AUTHOR]

In this study, we investigate the impact on shipping emissions from improving operational efficiency in a maritime chokepoint such as a canal. We consider several scheduling proposals that allow for different levels of speed reduction for incoming vessels and estimate the resulting emission reduction compared to a benchmark established from ship position data. For our case study of the Panama Canal, we estimate that the canal could have removed up to 1.8 million tonnes of CO 2 e per year for the period of 2019 to 2021. Our findings suggest that emission reduction can be easier to obtain at intermediate points as many of the contractual barriers to improving operational efficiency do not apply. [ABSTRACT FROM AUTHOR]

A large body of transport sector-focused research recognizes the complexity of human behavior in relation to mobility. Yet, global integrated assessment models (IAMs), which are widely used to evaluate the costs, potentials, and consequences of different greenhouse gas emission trajectories over the medium-to-long term, typically represent behavior and the end use of energy as a simple rational choice between available alternatives, even though abundant empirical evidence shows that real-world decision making is more complex and less routinely rational. This paper demonstrates the value of incorporating certain features of consumer behavior in IAMs, focusing on light-duty vehicle (LDV) purchase decisions. An innovative model formulation is developed to represent heterogeneous consumer groups with varying preferences for vehicle novelty, range, refueling/recharging availability, and variety. The formulation is then implemented in the transport module of MESSAGE-Transport, a global IAM, although it also has the generic flexibility to be applied in energy-economy models with varying set-ups. Comparison of conventional and ‘behaviorally-realistic’ model runs with respect to vehicle purchase decisions shows that consumer preferences may slow down the transition to alternative fuel (low-carbon) vehicles. Consequently, stronger price-based incentives and/or non-price based measures may be needed to transform the global fleet of passenger vehicles, at least in the initial market phases of novel alternatives. Otherwise, the mitigation burden borne by other transport sub-sectors and other energy sectors could be higher than previously estimated. More generally, capturing behavioral features of energy consumers in global IAMs increases their usefulness to policy makers by allowing a more realistic assessment of a more diverse suite of policies. [ABSTRACT FROM AUTHOR]

Although the aviation sector is a relatively small contributor to total greenhouse gas emissions, it is a fast-growing, fossil fuel-intensive transportation mode. Because aviation is a mode for which liquid fuels currently have no practical substitute, biofuels are gaining attention as a promising cleaner alternative. In this paper, we use the GCAM integrated assessment model to develop scenarios that explore the potential impact of biojet fuels for use in aviation in the context of broader climate change mitigation. We show that a carbon price would have a significant impact on the aviation sector. In the absence of alternatives to jet fuel from petroleum, mitigation potential is limited and would be at the expense of aviation service demand growth. However, mitigation efforts through the increased use of biojet fuels show potential to reduce the carbon intensity of aviation, without a significant impact on bioenergy use in the rest of the energy system for carbon mitigation. The potential of biofuel to decarbonize air transport is significantly enhanced when carbon dioxide capture and storage (CCS) is used in the conversion process to produce jet fuels from biomass feedstock. [ABSTRACT FROM AUTHOR]

The environmental problems brought by the shipping industry have drawn the attention of all parties, making it critical to select a fuel system that combines economic and environmental benefits when ordering new ships. This paper narrows down a list of fuels to four high-potential options: LNG, methanol, hydrogen, and ammonia. Based on the dual perspectives of shipowners and the public, this study takes different-sized ships as the object, establishes mathematical models throughout their life cycle, and selects a variety of indicators to evaluate alternative fuels. The findings demonstrate that, in the short term, heavy fuel oil with scrubbers is the most economically advantageous option for all sizes of container ships, but methanol is a desirable alternative when taking into account the social cost of pollutants. Hydrogen might be the ultimate fuel to reduce emissions in the long run when the price gap closes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Transition modeling considers the phase-in and -out of technologies and time delays. • Electrification speed is the most important factor toward a carbon-neutral car fleet. • Swiss climate goals can be met by phasing out new ICEVs by 2025 and hybrids by 2030. • Electric autonomous cars with ride-sharing will yield the largest emissions reduction. • Autonomous cars without shared mobility will lead to the highest emissions levels. Car transport is currently undergoing three simultaneous revolutions that are co-shaping the pathway to low-carbon mobility: fleet electrification, shared mobility, and autonomous cars (ACs). So far, studies of the climate impacts have mostly focused on the revolutions in isolation, neglecting potential synergies, and using methodologies that poorly represent the long-term transition of physical systems such as the car fleet. Here, we developed a stock dynamics model and a scenario analysis for direct energy consumption and greenhouse gas (GHG) emissions generated by different combinations of the revolutions in Switzerland. The largest climate change mitigation potential is provided by combining ACs with ride-sharing with rapid fleet electrification, i.e. completely phasing out new gasoline and diesel cars by 2025 and new hybrid cars by 2030. By contrast, ACs without shared mobility generate the lowest mitigation potential. Electric ACs with ride-sharing are crucial for meeting the Swiss climate goals, e.g. carbon neutrality in 2050. [ABSTRACT FROM AUTHOR]

• A framework for bridge scour risk management in an uncertain climate future. • A systematic approach to estimating scour risk ratings in different climate scenarios. • Local scour progression is fastest during the initial 48 h of a peak flow event. • Accelerated scour risk progression even in low emission climate scenario (RCP2.6). Riverine bridges are under a substantial threat of scour due to the magnitude and frequency of floods arising due to climate change. Infrequent inspections, inadequate data on foundation depths, and the lack of consideration of hydrologic and climate parameters often result in uncertainties within current scour risk assessments. This paper presents an approach for assessing the risk progression of local scour in peak flow conditions that consider uncertainties associated with location, downscaling of climate predictions, and hydrologic, hydraulic and scour prediction models. A rational scour risk rating based on warning time to failure is introduced that can provide a useful addition to the existing bridge condition indexes. The case study on a set of railway bridges in Southeast England shows that climate change could accelerate the scour risk progression, even in the low-emission scenario. The approach and results form a vital basis for scour risk mitigation and climate adaptation planning. [ABSTRACT FROM AUTHOR]

Recent years, air pollution phenomenon has become one of the crucial problems of Tehran, Iran. Due to main political and economic role of Tehran, population of this metropolis is high and increasing. Urban transportation of this highly populated city contributes more than 70% of air pollution problem in this city. Although a number of urban transport developments, policy measures and regulations have been employed, Tehran’s air pollution has remained crucial thus far. Finding ways to encourage individuals to behave more sustainable can be considered as a substantial approach of tackling environmental problems such as air pollution, since it can be highly cost-effective and fast. This research attempt to evaluate the impacts of two factors of outcome framing and psychological distance of air pollution on citizen’s willingness to behave environmental friendly, particularly to change the travel mode choice. Results illustrate that communicating the consequences of air pollution can provoke individuals’ to act more environment friendly or in particular to change their intention for using more sustainable mode of transportation. Framing the positive consequences of mitigating air pollution take precedence over framing the negative consequences. Moreover the gains of mitigating air pollution have an impact on the willingness to use of bicycle and bus. Results also show that decreasing the psychological distance of air pollution in order to make manipulated frame more personally relevant has no significant impact on respondents. [ABSTRACT FROM AUTHOR]

Air traffic has an increasing influence on climate; therefore identifying mitigation options to reduce the climate impact of aviation becomes more and more important. Aviation influences climate through several climate agents, which show different dependencies on the magnitude and location of emission and the spatial and temporal impacts. Even counteracting effects can occur. Therefore, it is important to analyse all effects with high accuracy to identify mitigation potentials. However, the uncertainties in calculating the climate impact of aviation are partly large (up to a factor of about 2). In this study, we present a methodology, based on a Monte Carlo simulation of an updated non-linear climate-chemistry response model AirClim, to integrate above mentioned uncertainties in the climate assessment of mitigation options. Since mitigation options often represent small changes in emissions, we concentrate on a more generalised approach and use exemplarily different normalised global air traffic inventories to test the methodology. These inventories are identical in total emissions but differ in the spatial emission distribution. We show that using the Monte Carlo simulation and analysing relative differences between scenarios lead to a reliable assessment of mitigation potentials. In a use case we show that the presented methodology can be used to analyse even small differences between scenarios with mean flight altitude variations. [ABSTRACT FROM AUTHOR]

This paper presents an integrated analysis of the costs and benefits of carefully constructed scenarios for the electrification of transport in Australia. Scenarios were constructed to responsively meet increased electricity demand, whilst maximising emission reduction, household finances and public health benefits. The scenarios bundle several technologies, including charging infrastructure, electric vehicles, home battery systems, and renewable energy. The fastest, mission-style, adoption scenario can reduce emissions by 9% of the 2030 carbon budget and reduce the loss of life by 24,000 by 2042. In all scenarios, government expenditure is dwarfed by the estimated public benefits, and households are nearly always better off in the medium to long term. Demonstrating the feasibility and advantages of surface transportation electrification in Australia, which presents cross-sections of rural and urban infrastructure, traffic and a large, socially and politically diverse population, provides broadly applicable evidence of the feasibility of electrification in other jurisdictions. [ABSTRACT FROM AUTHOR]

The study develops scenarios regarding the introduction of electric vehicles to the passenger vehicle fleet of Norway to reach the 2020 Norwegian greenhouse gas reduction target and a more extreme target to limit global temperature increase to two degrees. A process-based life cycle assessment approach is integrated with a temporally variable inventory model to evaluate the environmental impacts of these scenarios. We find that greenhouse gases in the reference scenario increase by 10% in 2020 in comparison to 2012; while for the more intensive improvements in conventional vehicles, this increase is reduced to 2%. For electric vehicles deployment scenarios, although the fleet share will reduce the tailpipe greenhouse gas emissions by 8–26%, with the upper end representing the two-degree reduction target, emissions reductions over the entire life cycle are only 3–15%. Electric vehicles also reduce emissions of NO x , SO 2 and particulates reducing acidification, smog formation and particulate formation impacts, however, with addition of large numbers of electric vehicles significant trade-offs in toxicity impacts are found. [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]

• This study explored concepts and perspectives underpinning the future urban road. • Through a systematic literature review, 28 transforming concepts were identified. • The concepts were organised into five categories: efficiency, safety, liveability, accessibility, and technology. • Our Q-method classified transport experts according to their perspectives into: People-First Techno-Centrists, Autonomous Vehicles Sceptics, Unconventionalists and Infrastructurists. • Our work is scene-setting opening up a new, dynamic, interdisciplinary and holistic dialogue about the future of urban roads. In an era of complexity, rapid technological advance and need for climate change action, urban roads may need to transform. The aim of this research is to identify the concepts underpinning the fundamental dimensions of the future urban road and open up an interdisciplinary dialogue about its delivery. We used a combinatorial approach incorporating a Systematic Literature Review to a Q-method. The Systematic Literature Review identifies 28 transforming concepts and organises them into five categories, namely: efficiency, safety, liveability, accessibility, and smart technology. Through a Q-method study, 50 transport experts "described" the urban road of the future. Four main factors emerged classifying the experts into: People-First Techno-Centrists (smart technology used as an enabler of human-centric transport futures), Autonomous Vehicles Sceptics , (AVs should not be the key paradigm-changer) Unconventionalists (shared road space and mixed uses should prevail) and Infrastructurists (safety-first multimodal infrastructure interventions should lead any change). The main dilemmas that arise are: a) prioritisation of modes: human first or not? b) share or segregate? and c) design systems or roads? [ABSTRACT FROM AUTHOR]

• We explore the agency for energy efficiency in all major types of ship operations. • How do voyage planning and execution decisions affect energy efficiency? • Commercial decisions matter more for energy efficiency than operational decisions. • Networked agency for energy efficiency limits climate change mitigation potential. • Policymakers should expand regulatory focus to cargo owners to reduce emissions. To mitigate climate change due to international shipping, the International Maritime Organization (IMO) requires shipowners and ship technical managers to improve the energy efficiency of ships' operations. This paper studies how voyage planning and execution decisions affect energy efficiency and distinguishes between the commercial and nautical components of energy efficiency. Commercial decisions for voyage planning depend on dynamic market conditions and matter more for energy efficiency than nautical decisions do for voyage execution. The paper identifies the people involved in decision-making processes and advances the energy-efficiency literature by revealing the highly networked nature of agency for energy efficiency. The IMO's current energy efficiency regulations fail to distinguish between the commercial and nautical aspects of energy efficiency, which limits the ability to mitigate climate change through regulatory measures. Policymakers should expand their regulatory focus beyond shipowners and technical managers to cargo owners to improve energy efficiency and reduce maritime transport emissions. [ABSTRACT FROM AUTHOR]

Abstract: In this paper a life cycle perspective is used to analyse Europabanan, a proposed high-speed rail track in Sweden. The life cycle emissions reductions are found to be 550,000tons of CO2-equivalents per annum by 2025/2030 with almost 60% of this coming from a shift from truck to rail freight and 40% from a shift from air and road travel to high-speed rail travel. In contexts similar to Sweden, it is thus an important issue whether a large increase is required in freight rail capacity anyway, since high-speed rail investments may not be justified for the passenger markets alone. The study also indicates that a substantial share of emissions due to construction of the new railway could be counterbalanced through the reduced need for building and maintaining roads and airports, and for manufacturing cars. [Copyright &y& Elsevier]

Abstract: Urban car transportation is a cause of climate change but is also associated with additional burdens such as traffic congestion and air pollution. Studies of external costs and potential impacts of travel demand management help to define policy instruments that mitigate the damaging impact of transportation. Here, we analyze different externalities of car transportation in Beijing and show that social costs induced by motorized transportation are equivalent to about 7.5–15.0% of Beijing’s GDP. Congestion and air pollution contribute the most with climate change costs being the most uncertain. We show that a road charge could not only address congestion but also has environmental benefits. The paper investigates the role of demand elasticities and demonstrates that joint demand and supply-side policies provide considerable synergies. [Copyright &y& Elsevier]

• Electrification is an attractive option to reduce CO 2 emissions from transport. • Alternative electrification options differ in terms of impact on the energy system. • Indirect electrification might result in a critical burden on the supply sector. • Policies addressing consumer preferences are crucial to trigger mobility shift. There is a wide consensus that a fundamental technology shift within the light duty vehicles (LDVs) sector is necessary to achieve the emissions reductions required for the Paris Agreement's targets, but substantial controversy prevails about the most suitable strategy. While some decision makers favor a transition to battery electric vehicles, others advocate for fuel cell vehicles and e-fuels. These strategies differ markedly in terms of consumer acceptance and implications for the energy system. We explore a range of electrification pathways in Europe until 2050. Direct electrification leads to a strong reduction in direct CO 2 emissions of LDVs, with electric vehicles reaching 90% of sales in 2050. Indirect electrification places substantially higher pressure on the supply sector, with almost double the primary energy demand relative to direct electricity use. In addition, the implementation of complementary policies addressing perceived inconvenience markups for alternative mobility is crucial to initiate the mobility transformation. [ABSTRACT FROM AUTHOR]

• Universities need to raise awareness of the effect of mobility on climate change. • The travel behaviour and CO 2 emissions of university commuters are analyzed. • A methodology to estimate CO 2 emissions factors by transport mode in Madrid. • Policies are recommended to reduce the impact on climate change from transport to the UPM. Cities are at the core of global climate change mitigation and strategic low-carbon development. Within cities, universities are ideal places to raise awareness of environmentally friendly lifestyles. This paper focuses on understanding per-trip commuting CO 2 emissions in the Technical University of Madrid. A simple mobility survey was conducted collecting 2149 responses. The study includes a methodology to estimate CO 2 emission factors by transport mode in Madrid. The results show that public transport is the main mode used, with over 75% of trips. However, users of private modes produce more than 55% of the total CO 2 emissions from commuting. After an analysis of UPM commuters' travel behaviour and their climate change impacts, a set of reduction policies -such as campaigns to promote shared mobility, economic incentives in public transport, and integrated parking management policies among others are proposed to redefine policies after the pandemic crisis. [ABSTRACT FROM AUTHOR]

• Banning new internal combustion engine cars reduce tailpipe CO 2 emissions. • A ban in 2030 is not sufficient for reaching Swedish climate targets for 2030. • An earlier ban year or increased biofuel use is needed to reach targets. • Regulation of carbon footprints for new vehicles and/or batteries may be motivated. • Prospective lifecycle assessment and vehicle fleet turnover simulations are used. Banning sales of passenger cars with internal combustion engines is becoming a common climate change mitigation policy. This study analyzes the effects of such a ban on the carbon footprints of passenger car travel in Sweden using a novel vehicle turnover model and prospective lifecycle assessment, with scenarios for decarbonization of supply chains. A ban on internal combustion engines results in significantly decreased carbon footprints primarily due to reduced tailpipe CO 2 emissions. The full effect of a ban is delayed due to fleet inertia. Increasing the pace of electrification is beneficial for the carbon footprint regardless of global manufacturing decarbonization pathways. A ban in 2030 is not sufficient to reach national policy targets for the transport sector, requiring either an earlier ban (i.e., 2025) or increased biofuel use. Risks of carbon leakage may motivate extending current regulations of vehicle-specific tailpipe emissions to also cover carbon footprints for new cars. [ABSTRACT FROM AUTHOR]

• How much CO 2 can be saved by walking, cycling and e-biking in towns and cities? • Cyclists had 84% lower CO 2 emissions from all daily travel than non-cyclists. • Life cycle CO 2 emissions decreased by 14% for each additional cycling trip. • The top 10% of participants were responsible for 59% of life cycle CO 2 emissions. • Regular cycling was most strongly associated with reduced life cycle CO 2 emissions for commuting and social trips. Active travel (walking or cycling for transport) is considered the most sustainable form of personal transport. Yet its net effects on mobility-related CO 2 emissions are complex and under-researched. Here we collected travel activity data in seven European cities and derived life cycle CO 2 emissions across modes and purposes. Daily mobility-related life cycle CO 2 emissions were 3.2 kgCO 2 per person, with car travel contributing 70% and cycling 1%. Cyclists had 84% lower life cycle CO 2 emissions than non-cyclists. Life cycle CO 2 emissions decreased by −14% per additional cycling trip and decreased by −62% for each avoided car trip. An average person who 'shifted travel modes' from car to bike decreased life cycle CO 2 emissions by 3.2 kgCO 2 /day. Promoting active travel should be a cornerstone of strategies to meet net zero carbon targets, particularly in urban areas, while also improving public health and quality of urban life. [ABSTRACT FROM AUTHOR]

• Establishment-level analysis to put a price on greenhouse gas emission in freight transport sector. • Latent class analysis to divide establishments based on fleet-ownership patterns. • Examines the determinants of freight transport emission disaggregated by fleet segments. • Gross emitters in each fleet ownership segment are modeled for targeted policy interventions. • Implications for designing carbon tax and trading programs in developing economies like India. Concerns over transport energy consumption and greenhouse gas emissions have lately prompted significant attention towards vehicle ownership patterns and the distributional implications of climate mitigation policies. This paper contributes to freight transport literature by examining how establishments can be meaningfully grouped using their fleet ownership pattern (size and composition) and how these segments vary in their freight travel pattern and CO 2 emission levels. The analysis performed using an establishment-based freight survey dataset from Kerala, a coastal state in India, revealed five latent classes of fleet ownership. The determinants of freight transport emissions and the gross emitters in fleet segments are presented subsequently by analyzing how the establishment-level characteristics (employment, business age, industry sector, value density, and relative location) explain the variation in CO 2 emissions. The study findings offer insights for designing effective carbon policy instruments and incentive schemes to regulate the establishment-level freight travel pattern and control transport emissions. [ABSTRACT FROM AUTHOR]

• First study to quantitatively compare climate change mitigation and adaptation for two ports. • Three market relationships are considered, i.e., independent, strategic substitute, strategic complement. • Both mitigation and adaptation increase the executing port's output. • Adaption decreases the other port's output if the two ports are independent or strategic substitutes. • A numerical case study on four Chinese ports based on the model is implemented. The two major approaches that seaport operators adopt to address climate change impacts are mitigation (CCM), i.e., reducing greenhouse gas emissions, and adaptation (CCA), i.e., adjusting the facility to moderate the negative outcomes of climate change. This paper is among the first to construct an economic model to compare the impacts of CCM and CCA in affecting the outputs of the executing port and the other ports in its network, considering the effects of market interactions. We find that both strategies can increase the executing port's cargo traffic, and can either increase or decrease the other port's cargo traffic depending on the market relationships between the ports. We also implement a numerical case study on four Chinese ports (Ports of Shenzhen, Xiamen, Tianjin and Hong Kong) based on our model. [ABSTRACT FROM AUTHOR]

• Land transportation pathways towards 1.5 °C scenario for 4 countries are presented. • The avoid/shift/improve approach is used to create a 1.5 °C scenario for each country. • Ambitious pledges in transportation will be necessary for updated countries' NDCs. • A 1.5 °C scenario will require the implementation of a wide range of policies and measures. • These will reflect commitments tovery low CO 2 vehicle technologies, energy systems, and travel patterns. Decarbonizing transportation in emerging economies will be one of the key challenges in global climate change mitigation efforts. In this paper, pathways are developed towards achieving a 1.5° degree scenario for land-transport for four emerging economies (Brazil, India, Kenya and Vietnam). The aim is to highlight the key opportunities and challenges for low-carbon transport in countries with rapidly growing mobility demand. The main focus of this paper is to reconcile actual and required emission reduction targets and develop plausible pathways to achieve these targets. The paper also identifies potential strategies and measures for these countries to follow these pathways. The analysis considers the contributions of "avoid" (cutting travel growth), "shift" (to lower CO 2 modes) and "improve" (vehicle and fuel CO 2 characteristics) interventions to decarbonisation scenarios. These scenarios aim to inform renewed Nationally Determined Contributions and shed light on the feasibility of deep decarbonisation pathways that would be in line with the Paris Agreement. Results from this study show that achieving 1.5DS would require dramatic changes in travel patterns, technology and fuels, and major intensification of current policy approaches. Decarbonization solutions will need to include greater use and investment of efficient modes, major shifts toward near-zero carbon fuels such as clean electricity, systems integration, modal shift and urban planning solutions. Although the socio-economic situations and national transport systems differ between the selected countries, some fairly similar strategies appear likely to be core to the mitigation effort, such as rapid growth in light- and heavy-duty vehicle electrification and investments in public transit systems. [ABSTRACT FROM AUTHOR]

• The paper studies how established practices influence climate mitigation futures. • It focuses the assessment practices of Swedish long-term infrastructure planning. • Established practices come to define what is considered relevant knowledge. • Alternative assessment practices and development directions are marginalized. • In effect, democratic discussion on potential mitigation pathways is constrained. Deep uncertainties in planning and policy-making related to climate mitigation pathways actualises the need for transport planning practices that embrace exploration and assessments of alternative future development directions. While conventional, forecast-based assessment practices are acknowledged to be of limited relevance in assessing potential trend-breaking developments, those practices have become strongly institutionalised and proven difficult to challenge. Applying a discourse perspective, this paper contributes with a practice-oriented analysis of how knowledge perspectives and established assessment practices influenced the consideration of alternative development directions and policy measures in the Swedish 12-year National Investment Plan for road and rail infrastructure 2018–2029. More specifically, the analysis regards how alternative futures and measures aimed at supporting a more 'transport efficient society' were addressed and assessed. The analysis illuminates a strong influence of established practices over the definition of what is considered relevant knowledge, in constructing an understanding of transport infrastructure investments as insignificant to climate mitigation, and in legitimizing the marginalization of alternative development directions. In effect, the study shows how established practices may result in significant democratic consequences, when public and political discussion over transport futures and climate mitigation pathways is constrained by a narrow span of possible futures presented. [ABSTRACT FROM AUTHOR]

• Synergism between plug-in hybrid cars and sugarcane-based ethanol and bioelectricity. • Cost competitive vehicle technologies that yield negative emissions and costs. • Sugarcane energy carriers fuel 1 billion cars, using only 60 million hectares. • Technical and economic aspects of various passenger vehicle alternatives are assessed. Continuous effort to mitigate climate change relies on new technologies able to satisfy human demand for energy services with high energy efficiency and reasonable costs. We show that blending a well-known technology with recently introduced and proven technical advances can mitigate climate change in the road transport sector. Furthermore, the achievement of a reasonable cost target is proved to be true when internal combustion engines (ICE) light duty vehicles (LDVs), powered by gasoline fuel, are replaced by plug-in hybrid LDVs (PHEV), powered by ethanol and electricity produced from sugarcane, using well established technology. The only improvements in such ethanol producing technology are the addition of woody biomass to extend the operation of sugar mills and the capture of carbon dioxide (CO 2) generated during sugar fermentation into ethanol. Both actions are already adopted and well developed. The study quantifies greenhouse gas (GHG) emissions, expressed as carbon dioxide equivalent (CO 2 e) emissions and the present value cost for operation of a global fleet of 1 billion LDV over a 60-year period. The PHEV powered by sugar cane products reduces GHGs emissions partly through negative emissions, at a lower cost than gasoline fueled ICE vehicles or electric vehicles. Total potential GHG emission reduction is significant but lower than what is required for the transport sector to fulfill international commitments. Nevertheless, if 1 billion sugarcane-based PHEV hit the streets by the year 2060, 6.18 Gt CO 2 e/year can be avoided while the necessity of land for biomass plantation is kept at a reasonable value (86 Mha). [ABSTRACT FROM AUTHOR]

• Climate impact analysis of air transport from Germany. • Scenario dependent forecast of passenger flights from Germany. • Scenario dependent forecast of specific emissions by traffic regions. • Focus on both CO 2 and NO x emissions. • Forecast of climate impact effects for three scenarios up to the year 2100. Transport is considered to be a major contributor to emissions, resulting in a deterioration of local air quality and contributing to global climate change. The present paper focuses on how passenger flights departing from German airports contribute to global climate change. We describe in detail, how traffic forecasts for three scenarios entitled Reference, Free Play and Regulated Shift have been developed and how the resultant emissions have been quantified. Subsequently, we applied a climate model, providing insights into the very long-term climate effects under different assumptions on emissions up to the year 2100. The modelling framework shows that the development of emissions results from complex interactions of demand development and supply decisions, which highly influence the climate impact. With this paper, we show that an integrated, multi-disciplinary analysis can create valuable indicators and advice for transport policy decisions. [ABSTRACT FROM AUTHOR]