Analysis on bargaining about global climate change mitigation in international aviation sector

Understanding the basic interaction mechanism among nations surrounding the CO₂ emissions is critically important for the policy formulation analysis in aviation sector at present, especially for market-based measures such as emission allowance trading. We performed simulation analysis of the effects on pricing of emission allowances by including major players such as China and India into the hypothetical global CO₂ emission trading scheme according to non-cooperative game framework. In the presence of a negative public good, i.e., CO₂, we extended the Lindahl–Bowen–Samuelson condition to include a class of uncertainty typical in climate change policy into utility. By using the result, we explained, with some numerical examples, the welfare effects caused by the changes of factors, such as level of uncertainty, degree of risk averse, asymmetric utility structure, initial allocation among players, based on our model surrounding the bargaining of CO₂ emissions allocation games.     

Design and planning for green global supply chains under periodic review replenishment policies

We quantify the impact of jointly optimizing strategic network design and tactical inventory planning on the cost and CO₂ emissions of multi-echelon logistics networks. The obtained insights indicate that longer optimized replenishment cycles reduce a node’s transportation cost and CO₂ emissions but increase its inventory costs. Moreover, under a fixed replenishment cycle, a node’s service level increases when supplied by a satellite warehouse. Finally: (i) the costs of implementing optimal green network design decisions could be misleading if inventory planning is neglected, (ii) greening of supply chains could become expensive, (iii) current legislative CO₂ ton prices hardly influence logistics networks.     

The effect of a roundabout corridor's design on selecting the optimal crosswalk location: A multi-objective impact analysis

Crosswalks located at mid-block segment between roundabouts can provide a good balance among delay, carbon dioxide (CO₂) emissions, and relative difference between vehicles and pedestrians speed. However, when considering local pollutant criteria, the optimal crosswalk location may be different to that obtained for CO₂. This paper described a multi-objective analysis of pedestrian crosswalk locations, with the objectives of minimizing delay, emissions, and relative difference between vehicles and pedestrians speed. Accounting for the difference between global (e.g., CO₂) and local pollutants (monoxide carbon, nitrogen oxides, and hydrocarbons) was one the main considerations of this work. Vehicle activity along with traffic and pedestrian flows data at six roundabout corridors in Portugal, one in Spain, and one in the United States were collected and extracted. A simulation environment using VISSIM, Vehicle Specific Power, and Surrogate Safety Assessment Model models was used to evaluate traffic operations along the sites. The Fast Non-Dominated Sorting Genetic Algorithm (NSGA-II) was implemented to further search optimal crosswalk locations. The results yielded improvements to both delay and emissions by using site-optimized crosswalks. The findings also revealed that the spacing between intersections widely influenced the optimal crosswalk location along a mid-block section. If the spacing is low (<100 m), the crosswalk location will be approximately in 20%–30% of the spacing length. For spacing values between 140 and 200 m, crosswalks would be located at the midway position. When a specific pollutant criterion was considered, no significant differences were observed among optimal crosswalk data sets.     

Green accessibility: Estimating the environmental costs of network-time prisms for sustainable transportation planning

Accessibility, or the ease to participate in activities and obtain resources in a given environment, is crucial for evaluating transportation systems. Greater accessibility is often achieved by increasing individuals' potential mobility. However, potential mobility, if realized by motorized modes, can also generate negative environmental impacts such as fossil fuel consumption and greenhouse gas (GHG) emissions. While the negative environmental impacts of greater mobility are acknowledged, there has been a lack of research to validate those impacts using empirical data, especially considering variations in individuals' mobility levels. This paper presents a method for estimating the expected environmental costs of accessibility represented by a network-time prism (NTP). A NTP delimits all accessible locations within a network and the available time for an individual to present at each location given a scheduled trip origin and destination, a time budget and the maximum achievable speeds along network edges. Estimating the expected environmental costs of a NTP involves three steps: (1) semi-Markov techniques to simulate the probabilities to move along network edges at given times; (2) the speed profiles for reachable edges, and (3) a cost function that translates speeds into environmental impacts. We focus on air quality and employ the motor vehicle emission simulator MOVESLite to estimate the CO₂ emissions at both the edge and prism levels. We calibrate and validate the methods for experimental NTPs defined within the Phoenix, AZ, USA road and highway network using vehicles instrumented with GPS-enabled onboard diagnostic devices (OBD). We demonstrate the effectiveness of our method through two scenarios and investigate the impact of changes in mobility levels on the expected CO₂ emissions associated with the experimental NTPs.     

Using GIS tools to estimate CO2 emissions related to the accessibility of large retail stores in the Oulu region, Finland

Everyday traffic accounts for a significant share of overall greenhouse gas emissions, in particular carbon dioxide (CO₂). While several solutions have been proposed for decreasing the emissions, a new kind of land use planning is required in order to achieve long-term effects. This study focuses on the effect of large retail store locations in the urban structure on overall CO₂ emissions, by using the Oulu region, Finland, as a case study. The aim was to utilize GIS tools to assess store locations in terms of CO₂ emissions from private cars used for consumer traffic. In this case, not only are the locations of the existing and planned retail units investigated with respect to population distribution and car ownership, but the analysis is also carried out by regarding any location within the study area as a hypothetical site for a large retail unit. According to the applied method, CO₂ values are lowest near the centre of the studied region, the region with the highest population density, although the city centre itself did not turn out to be the most optimal location for a retail store in terms of CO₂ emissions. Nevertheless, by generally reducing trip length, a compact urban structure is an important way of achieving long-term cuts in CO₂ emissions.     

Hinterland operations of sea ports do matter: Dry port usage effects on transportation costs and CO2 emissions

Decreasing carbon dioxide (CO₂) emissions is one of the most important tasks for the society in the 21st century. One possibility to decrease emissions originating from transportation is to utilize more rails instead of relying simply on road transportation. In the dry port concept an inland intermodal terminal is connected to a sea port using railways. This study analyzes impacts of dry ports in a Finnish context. We compare two different configurations: In the first one shippers drive directly to a sea port, while in the second one they use dry ports. The systems are evaluated by using discrete-event simulation. In the systems we are interested in two issues: (1) Level of CO₂ emissions, and (2) Costs to transport the goods in different configurations. We use different scenarios for future energy prices and estimate both the costs and CO₂ emission development in these scenarios. We also compare the results to a situation, where emissions are minimized instead of costs. Implications on larger scale are also discussed, for example in the Baltic Sea and North Sea area, where strict sulfur emission restrictions are seen to harm sea transport and increase concentration on small number of sea ports.     

UK supply chain carbon mitigation strategies using alternative ports and multimodal freight transport operations

In the last few decades, the building evidence that CO₂e emissions lead to climate change has pointed to a need to reduce CO₂e emissions. This research uses five scenarios in the context of UK import trade to assess total CO₂e emissions and costs of import re-routing containers. The overall objective is to assess possible carbon mitigation strategies for UK supply chains by using a combination of alternative ports and revised multimodal strategies. The model adopted includes three elements: port expansion, container handling and freight transport. The alternative scenarios explore different settings modal shift and short sea shipping.     

CO2 emissions associated with hubbing activities in air transport: an international comparison

Hubbing is an important operational practice in air transport. Many studies have been conducted to examine the benefits and impacts of hubbing from an economic perspective. However, its impact on CO₂ emissions, especially across different air spaces, is not well understood. This paper explores the impact of hubbing activities in air transport from an environmental perspective. With a detailed methodology and data from the Greek and Hong Kong/Sanya flight information regions (FIRs), three levels of CO₂ emissions are estimated: airport-based, airspace-based and flight-based. After contrasting the CO₂ emission efficiencies of Athens International Airport (AIA) and the Hong Kong International Airport (HKIA), aircraft type and flight distance are examined to explain their emission efficiency differences. It is found that HKIA is associated with poorer CO₂ emission efficiency at the airport and airspace levels because of the larger aircraft and longer flight distance. However, when CO₂ emission efficiency at the flight level is considered, HKIA, with a higher passenger load factor, performs better. Major international hub airports should implement additional environmental measures to minimize the impact of hubbing activities on CO₂ emissions at the airport and airspace levels.     

Towards a theory of decoupling: degrees of decoupling in the EU and the case of road traffic in Finland between 1970 and 2001

Traditionally, the transport literature reflects the view that traffic volumes, road traffic volumes in particular, are coupled with Gross Domestic Product (GDP). Recently published literature also argues that the carbon dioxide (CO₂) emissions from transport, passenger cars in particular, have not shown any decoupling from transport volumes for some years. This article presents a theoretical framework for decoupling, defining the difference between decoupling, coupling and negative decoupling. These are further broken down to weak, strong and expansive/recessive degrees of decoupling, laying emphasis on the absolute increase or decrease of the variables. The result section presents data of the development of the relationships between GDP, traffic volumes and CO₂ emissions from transport in the EU15 countries between 1970 and 2001, including the special case of Finnish road traffic. The aggregate EU15 data show a change from expansive negative decoupling to expansive coupling regarding passenger transport, and from weak decoupling to expansive negative decoupling regarding freight transport. Weak decoupling of transport CO₂ emissions from GDP could also be observed. Weak decoupling of all the three aspects (freight, passenger and CO₂) could be seen in the UK, Sweden and Finland in the 1990s. In Finland, the statistics show weak decoupling of GDP from road traffic volume and strong decoupling of road traffic volume and CO₂ emissions from road traffic between 1990 and 2001. Four hypothetical explanations of the Finnish phenomenon are put forward in this article: policy towards sustainable mobility, green urban lifestyle, increasing income differences, and statistical misinterpretation. Each explanation is backed up with some quantitative evidence in observable trends in Finland during the 1990s.     

A carbon footprint analysis of renewable energy technology adoption in the modal substitution of high-speed rail for short-haul air travel in Australia

This study presents a carbon footprint analysis of renewable energy technology adoption in the modal substitution of high-speed rail for short-haul air travel in Australia. The carbon footprint analysis of renewable energy technology adoption in such modal substitution establishes the efficacy of various renewable energy technologies in assisting CO₂ emissions reduction on the Sydney–Melbourne city pair. Renewable energy technology efficacy, captured in the presented low-carbon pathways for high-speed transportation, provides an indication as to the CO₂ emissions reduction potential of the technologies under consideration and their impact upon the environmental performance of the air and high-speed rail modes. These low-carbon pathways displayed a reduction in annual CO₂ emissions throughout the longitudinal period ranging from moderate to significant. Furthermore, this study examines the cumulative effects of the considered renewable energy technologies upon the annual CO₂ emissions production of the high-speed transportation system. A reduction of 56%–69% in annual life cycle CO₂ emissions demonstrated the powerful mitigation potential of a combined air and high-speed rail transportation system in conjunction with renewable energy technologies adoption and a modal shift of 60%. Given this significant mitigation potential, the hybridization of the air and high-speed rail transportation systems with associated renewable energy technologies is considered. The effect of such hybridization would result in the formation of an integrated low-carbon, high-speed transportation system underpinned by the concept of “sustainable mobility” at the national level.     

PM,NOx and CO2 emission reductions from speed management policies in Europe

Speed reduction measures rank among the most common schemes to improve traffic safety. Recently many urban streets or entire districts were converted into 30 kph zones and in many European countries the maximum permissible speed of trucks on motorways is under discussion. However, besides contributing to traffic safety, reducing the maximum speed is also seen as beneficial to the environment due to the associated reduced fuel consumption and lower emissions. These claims however are often unsubstantiated.To gain greater insight into the impact of speed management policies on emissions, this paper examines the impact on different traffic types (urban versus highway traffic) with different modelling approaches (microscopic versus macroscopic). Emissions were calculated for specific types of vehicles with the microscopic VeTESS-tool using real-world driving cycles and compared with the results obtained using generalized Copert-like macroscopic methodologies. We analyzed the relative change in pollutants emitted before and after the implementation of a speed reduction measure for passenger cars on local roads (50–30 kph) and trucks on motorways (90–80 kph). Results indicate that emissions of most classic pollutants for the research undertaken do not rise or fall dramatically. For the passenger cars both methods indicate only minor changes to the emissions of NO_x and CO₂. For PM, the macroscopic approach predicts a moderate increase in emissions whereas microscopic results indicate a significant decrease. The effects of specific speed reduction schemes on PM emissions from trucks are ambiguous but lower maximums speed for trucks consistently result in lower emissions of CO₂ and lower fuel consumption. These results illustrate the scientific uncertainties that policy makers face when considering the implementation of speed management policies.     

Analysis of CO2 emissions for island ferry services

In this study CO₂ emissions are calculated for ferries operating on both short and long range sea routes between mainland Scotland and the Orkney Isles. CO₂ emissions for land transport options connecting with the respective ferry services are also analysed. In particular the study offers a comparison of transport CO₂ emissions for long-range ferry services between Aberdeen and the Orkney Islands and short-range ferry services across the Pentland Firth. The latter involve a longer road journey for vehicles than the former. The results indicate significantly greater CO₂ emissions for long-range ferry services, despite shorter road connections. Existing public policy in this regard specifies and subsidises higher CO₂ emission ferry services operating on longer sea routes, to the disadvantage of non-subsidised short crossing services, the latter offering much lower CO₂ emission impacts (inclusive of connecting land transport CO₂ emissions). This suggests that policymakers need to focus on assessing CO₂ emission impacts when considering future tenders for subsidised ferry services. Findings also suggest that, for modest sized ferries serving islands, the optimal solution may be to use/specify the shortest possible sea routes in order to reduce CO₂ emissions from transport.     

Transitions to low carbon transport futures: strategic conversations from London and Delhi

Climate change is a global problem and across the world there are major difficulties being experienced in reducing carbon dioxide (CO₂) emissions. The transport sector in particular is finding it difficult to reduce CO₂ emissions. This paper reports on two studies carried out by the authors in London (UK) and Delhi (India). It considers the common objectives for transport CO₂ reduction, but the very different contexts and baselines, potentials for change, and some possible synergies.Different packages of measures are selected and scenarios developed for each context which are consistent with contraction and convergence objectives. CO₂ reduction potentials are modelled and quantified by package and scenario. London is considering deep reductions on current transport CO₂ emission levels; Delhi is seeking to break the huge projected rise in transport CO₂ emissions.The scale of policy intervention required to achieve these goals is huge and there is certainly little public discussion of the magnitude of the changes required. The paper argues for a ‘strategic conversation’ at the city level, using scenario analysis, to discuss the priorities for intervention in delivering low carbon transport futures. A greater focus is required in developing participatory approaches to decision making, alongside network investments, urban planning, low emission vehicles and wider initiatives. Aspirations towards equitable target emissions may assist in setting sufficiently demanding targets. Only then is a wider awareness and ownership of potential carbon efficient transport futures likely to take place.     

Uncovering the spatiotemporal patterns of CO2 emissions by taxis based on Individuals' daily travel

Traffic-related carbon dioxide (CO₂) emissions have become a major problem in cities. Especially, the CO₂ emissions induced by taxis account for a high proportion in total CO₂ emissions. The availability of taxi trajectory data presents new opportunities for addressing CO₂ emissions induced by taxis. Few previous studies have analyzed the impact of human trips on CO₂ emissions. This paper investigates trip-related CO₂ emission patterns based on individuals' travel behavior using taxi trajectory data. First, we propose a trip purpose inference method that takes into account the spatiotemporal attractiveness of POIs to divide human trips into different types. Further, we reveal the spatiotemporal patterns of CO₂ emissions from various types of trips, including temporal regularity and periodicity as well as spatial distribution of “black areas”. Finally, comparative analysis of CO₂ emissions for different kinds of trips based on trip behavior is conducted using three variables, namely trip distance, trip duration and trip speed. This study is helpful for us to understand how to make travel and cities more sustainable through modifying people's trip behaviors or taxi trips.     

Tourism travel under climate change mitigation constraints

The paper first describes an inventory for 2005 giving the tourism related CO₂ emission caused by global tourism, and presents a 30-year projection and a 45-year simulation. The study found that tourists cause 4.4% of global CO₂ emissions. Also these emissions are projected to grow at an average rate of 3.2% per year up to 2035. This increase is problematic as globally a reduction of emissions by 3–6% is required to avoid ‘dangerous’ climate change. Using contemporary scenario techniques it appeared difficult to find a future tourist travel system consistent with CO₂ emission reductions of up to 70% by 2050 with respect to 2005. Based on the model underlying the 30-year projection, 70 scenarios are presented in a ‘landscape’ graph exploring the effect of opportunities to reduce the emissions, but this attempt did not reach the large reductions envisaged. We therefore explored automated scenario generation as a way to define backcasting scenarios that both reach the emission reduction target and retain the highest possible economic value for the sector. The main contributions made by this study are (1) in comparing the value of different ways to approach a (desired) future and (2) giving insight into the kind of structural changes required within tourism and tourism transport in case very strong emission reductions are required. Finally the model showed signs of ‘complex’ behaviour.     

How to regulate aviation's full climate impact as intended by the EU council from 2020 onwards

The EU Council intends to regulate air transport's full climate impact (i. e., CO₂ and NO_x, H₂O, SO_x, aerosols, contrails and contrail cirrus). A likely approach is the inclusion of all climate relevant species from aviation in the European Emissions Trading Scheme. We provide a proposal for this practice and analyze the economic impacts. Modelling results indicate that the cost effects of the EU-ETS addressing CO₂ and non-CO₂ emissions will be much larger than under the current scheme. This is because under the new approach, all climate relevant species are regulated and not just CO₂. The cost effects also depend on the length and altitude of the flight. Both have consequences for the competitive environment of the airlines under the scheme. Especially the full service network carriers will have to bear a competitive disadvantage compared to airlines offering just short- and medium-haul services. Remarkably, some cost effects are in opposition to the corresponding results for an ETS for the regulation of CO₂ alone.     

Carbon emission values in cost benefit analyses

New infrastructure projects may affect CO₂ emissions and, thus, cost benefit analyses for these projects require a value to apply for CO₂. This may be based on the marginal social cost of emissions or on the shadow price resulting from present and future policies. This paper argues that both approaches are necessary, but for cost benefit analysis of infrastructure projects the latter should be the primary tool. A series of complications arise when applying this principle in practice. These are discussed in the paper. Even if the complications make the implementation of a shadow price approach difficult, we argue that the approach still is preferable to a social cost approach.     

Investigations on the distribution of air transport traffic and CO2 emissions within the European Union

This study analyses the structure of air traffic and its distribution among the different countries in the European Union, as well as traffic with an origin or destination in non-EU countries. Data sources are Eurostat statistics and actual flight information from EUROCONTROL. Relevant variables such as the number of flights, passengers or cargo tonnes and production indicators (RPKs) are used together with fuel consumption and CO₂ emissions data. The segmentation of air traffic in terms of distance permits an assessment of air transport competition with surface transport modes.The results show a clear concentration of traffic in the five larger countries (France, Germany, Italy, Spain and UK), in terms of RPKs. In terms of distance the segment between 500 and 1000 km in the EU, has more flights, passengers, RTKs and CO₂ emissions than larger distances. On the environmental side, the distribution of CO₂ emissions within the EU Member States is presented, together with fuel efficiency parameters. In general, a direct relationship between RPKs and CO₂ emissions is observed for all countries and all distance bands. Consideration is given to the uptake of alternative fuels. Segmenting CO₂ emissions per distance band and aircraft type reveals which flights contribute the most the overall EU CO₂ emissions. Finally, projections for future CO₂ emissions are estimated, according to three different air traffic growth and biofuel introduction scenarios.     

Looking over the horizon: Transport and reduced CO2 emissions in the UK by 2030

Transport is a major user of carbon-based fuels, and achievement of the targets set at the Kyoto Protocol and elsewhere means that the EU and national governments must reduce CO₂ emissions in all sectors, including transport. This paper reports on a recently completed study for the UK government on the options available to meet a 60% CO₂ reduction target by 2030 in the UK transport sector. The study follows a backcasting study approach, developing a business as usual baseline for transport emissions, and two alternative scenarios to 2030. Different policy measures are assessed and assembled into mutually supporting policy packages (PP). Although 2030 seems a long way ahead, action must be taken now if the targets for CO₂ reduction are to be met. The achievement of a carbon-efficient transport future, combined with holding travel levels at present levels, is likely to be very difficult. A major transformation in the way transport and urban planning is carried out is required. As transport and urban planners, we need to think very differently in tackling the new environmental and liveability imperative.     

Critical aggressive acceleration values and models for fuel consumption when starting and driving a passenger car running on LPG

The models based on vehicle speed have been used to estimate fuel consumption and CO₂ emissions. However, these models could not properly estimate the change in fuel consumption and CO₂ emissions as the speed changes. As for the alternative method, people try to consider using acceleration instead of speed. Although acceleration has been seriously considered, determining critical aggressive acceleration value in relation to fuel consumption and CO₂ emissions is difficult to find. In this study, evaluation models of fuel consumption were developed using instantaneous acceleration, and we defined the critical aggressive acceleration values for different states of the vehicle from the viewpoints of fuel consumption and emissions. We used a mid-sized Liquefied Petroleum Gas (LPG) passenger car and obtained instantaneous data from a digital tachograph installed in the car while it accelerates. We developed two fuel consumption models and found critical aggressive accelerations, respectively: a model of starting vehicle that measures range of speed required to overcome the inertia during acceleration from stop state, and the other model for the driving state. We used Classification and Regression Tree (CART) analysis to find the critical aggressive accelerations at which the increments of fuel consumption change abruptly. As a result, the critical aggressive accelerations causing abrupt change in the increments of fuel consumption were found to be 2.598 m/s² for the starting of vehicles and 1.4705 m/s² when driving them. We also found that the increments of fuel consumption can be explained through quadratic and exponential functions with instantaneous acceleration.