Assessment of transport emissions impact and the associated social cost for Chengdu,China

Chengdu, the capital city of Sichuan province, is the fourth biggest city in China with over 15 million residents and 3.4 million vehicles. In Chengdu, transport and other mobile sources accounted for over 27% of the city's PM_2.5 emissions (CDEPB, 2016), posing negative impacts on public health, local environment, and the climate. This study estimated impacts from transport-related emissions (CO₂, CH₄, N₂O, PM₁₀, PM_2.5, NO_X, SO_X, CO, and HC) and evaluated the associated social cost for Chengdu from 2005 to 2013. The study also assessed the city's transport performance in terms of its eco-efficiency with the socioeconomic and environmental concerns. The activity-based methodology was adopted to produce the emission inventories, while utilizing meta-analysis and localizing the emission social cost factors based on Chengdu's economic and demographic reality to support social cost assessment. The study marks the first attempt in literature to evaluate Chengdu's transport emission social cost. The following were observed in the study: (i) in 2013, the social cost of all transport emissions in Chengdu was around US$3 billion, with the lowest estimate of US$449 million and the highest estimate of US$4.7 billion; (ii) trucks, private cars, and motorcycles were the major contributors, while NO_X, PM_2.5, and CO were the key pollutants to public health; (iii) if GHGs (CO₂, CH₄, and N₂O) were excluded, the upper range of social cost of transport air pollutants would be from US$2.4 billion to US$4.1 billion, or 1.6%–2.8% of the Chengdu's GDP.     

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.     

Urban bus fleet-to-route assignment for pollutant emissions minimization

This study proposes a methodology to optimize the assignment of an urban bus fleet to a set of fixed routes, taking into account the differences among routes and the differences among vehicle types and propulsion technologies in order to reduce pollutant emissions (CO₂, CO, THC, NO_x and PM). A Mixed Integer Linear Programming optimization model is stated and two scenarios are assessed: minimization of CO₂ and NO_x. The results show that it is feasible to obtain a fleet distribution in which emissions for any given pollutant are reduced without increase in emissions of other pollutants.     

Ex-post environmental and traffic assessment of a speed reduction strategy in Madrid's inner ring-road

Since urban traffic is a major source of CO₂ and NO_x emissions, cities play a key role averting climate change and combating air pollution. Most researchers agree on the need of designing comprehensive mitigation strategies instead of applying isolated measures. Nevertheless, it is important to understand the specific impact and scope of each measure to look for the most effective synergies among them. In 2004, the Madrid City Council launched a plan to re-design its inner ring-road to move traffic out of the city centre. For safety reasons the planned speed limit for the full-renovated South-West section was finally reduced from 90 km/h to 70 km/h. Besides contributing to traffic safety, this strategy could also be seen as positive to the environment due to the associated reduced fuel consumption and lower emissions. However, lower speed limits have lower rates of community acceptance due to its impact on average travel times at the individual level. This paper conducts an ex-post evaluation of this speed reduction strategy to explore its environmental and traffic performance impacts. The results support the thesis that, in this velocity range, lower speed limits present important opportunities for reducing GHG and air pollution in the section affected by the measure, without substantially altering traffic performance. The implementation of the new speed limit policy produces a 14.4% and 16.4% reduction in CO₂ and NO_x emissions respectively, while global travel time remains virtually constant and the saturation rate decreases slightly. Besides, this cost-effective measure reveals great potential to reduce air pollution in highly populated urban areas located next to urban highways. This work provides local policy makers and city managers with useful insights regarding potential co-benefits of traffic optimization and speed reduction management to reduce mobile source emissions in urban environments.     

Tourism development and economic growth: a panel Granger causality analysis in the frequency domain

In this paper, we test the causal relationship between economic growth and tourism development in the 1995–2012 period using recently developed panel Granger causality tests that allow for country-level heterogeneity, thus leading to more accurate results for the 12 Mediterranean countries. Although results of the Dumitrescu and Hurlin [(2012) testing for Granger non-causality in heterogeneous panels. Economic Modelling, 29(4), 1450–1460] panel Granger causality test show a unidirectional causality from tourism development to economic growth, results of the Croux and Reusens [(2013). Do stock prices contain predictive power for the future economic activity? A Granger causality analysis in the frequency domain. Journal of Macroeconomics, 35, 93–103] panel Granger causality analysis in the frequency domain show that there is a bidirectional temporary and permanent causality between tourism development and economic growth. The bidirectional causality relationship between tourism development and economic growth, which is the main finding of this study, suggests that in order to achieve high economic growth, policy-makers should focus on developing the tourism sector.     

Examining the carbon emission impact of livelihood transitions in pro-poor tourism

This study examines carbon dioxide (CO₂) emission changes from livelihood transitions during tourism development to assess the environmental impact of pro-poor tourism (PPT) in China. The results indicate that livelihood transitions during PPT increased household income but also produced more CO₂ emissions. CO₂ emissions vary depending on factors including livelihood types after transition, income and household sizes, etc. The CO₂ per unit of income from tourism-based livelihoods is higher than from non-tourism-based livelihoods. Different livelihood strategies post transition also affect emissions. Practical suggestions that may mitigate emissions while not compromising residents’ income levels are provided.     

Dynamic linkages between tourism transportation expenditures,carbon dioxide emission,energy consumption and growth factors: evidence from the transition economies

Tourism transport profoundly affects economic growth, energy consumption and carbon dioxide emissions. This study is an attempt to examine the impact of international tourism transportation expenditures, energy demand, foreign direct investment inflows, trade openness and urban population on carbon dioxide emission and per capita income for the panel of 11 transition Economies, over the period of 1995–2013. The results show that per capita income escalates the carbon dioxide emission (CO₂), which deteriorates the natural environment. International tourism receipts and international tourism expenditures for travel items are associated with the intensifying CO₂ emission and per capita income in the region. The study confirmed the energy-led emissions, FDI-led emissions, FDI-led growth, income-led emissions, income-led energy demand, trade-led growth and trade-led energy demand. The causality results further substantiate the the tourism-led growth and FDI hypothesis in the region. Finally, the variance decomposition analysis confirmed the following results, that is, (i) per capita income is the contributor that least influences CO₂ emissions, (ii) urban population influences per capita income and (iii) international tourism transportation expenditures will influence CO₂ emissions and per capita income for the next 10-year period.     

Will new technology be sufficient to solve the problem of air pollution caused by Swedish road transport?

In this article, levels of future specific vehicle emissions and the energy efficiency required to match long-term environmental targets are estimated. The possibility of reaching these targets is also evaluated. It appears to be possible to achieve sufficiently large reductions in both nitrogen oxide (NO_x) and non-methane volatile organic compound (NMVOC) emission to meet long-term Swedish environmental requirements even with continuing transport growth. Combining sufficiently large carbon dioxide reductions with transport growth seems to be more difficult and would require major breakthroughs regarding drive systems, materials and vehicle construction. Such technological developments cannot, however, be entirely ruled out.     

Development of air pollutant emission factors under real-world truck driving cycle

The truck driving cycle was developed in Thailand using actual speed-time profile from trucks in suburban area. Driving data were separated into micro trips and the representative driving cycle was selected by matching micro trips statistics and target statistics. The Performance Value (PV) was considered for selecting the representative driving cycle. This selected driving cycle was then used as input data for estimating emission factors of 4 air pollutants and 3 greenhouse gases by the International Vehicle Emission (IVE) model. Results were then compared with emission factors developed using the European Transient Cycle (ETC). Additionally, a comparison was made between emission factors calculated in this study and direct measurements of emissions from truck driven on chassis dynamometer under the European driving cycle. Comparison results revealed that CO, NO_x and CO₂ emission factor were about 2.05, 2.24 and 1.78 times lower than those obtained from direct measurements. PM emission factor was about 0.89 times higher than measured data. This study confirms the need to considered actual fleets and characteristics of vehicular sources when calculating their emission rates for further use in development of emission inventory.     

Modeling different penetration rates of eco-driving in urban areas: Impacts on traffic flow and emissions

Climate change and air quality are two main environmental challenges in metropolitan areas. As road transportation is one of the main contributors, public administrations are facing these problems with a number of complementary policy measures: shift to cleaner modes, new fuels and vehicle technologies, demand management, and the use of information and communication technologies (ICT) applied to transportation. Eco-driving is one of the measures that present large fuel savings at individual level. Although these savings are well documented in the literature, few studies focus on how eco-drivers driving patterns affect the surrounding vehicles and the traffic in general, and more particularly what would be the impact when the number of eco-drivers grows. Using a traffic microsimulation tool, four models in urban context have been built, corresponding to the different types of urban roads. Both the base-case and the parameters setting to simulate eco-driving have been calibrated with real data collected through floating vehicles performing the trips with normal and eco behaviors. In total, 72 scenarios were simulated, varying the type of road, traffic demand, and the percentage of eco-drivers. Then, the CO₂ and NO_x emissions have been estimated through a microscopic emission model. The results show that in scenarios with low or medium demand levels and increasing number of eco-drivers, the effects are positive in terms of emissions. On the other side, with high percentage of eco-drivers and high traffic demand, the emissions rise. Higher headways and smooth acceleration and decelerations increase congestion, producing higher emissions globally.     

Profiling road transport activity: Emissions from 2000 to 2005 in Ireland using national car test data

This work describes a methodology for determining the average vehicle kilometres travelled by the private national car fleet in Ireland and estimating the disaggregated CO₂ and NO_x emissions from private vehicles in the Irish road transport sector for the period 2000–2005 using national car test records. The developed methodology facilitates the calculation of greatly improved estimates for vehicle kilometres under a range of constraint variables and thereby enables the disaggregated analysis of specific vehicle fleet groups and their associated activity patterns to support evidence-based policy development. The results indicate that while older vehicles are contributing significantly to car NO_x emissions; newer cars produce a higher share of CO₂ emissions than older cars in the vehicle fleet.     

Responsive relationship between energy-related carbon dioxide emissions from the transportation sector and economic growth in Beijing—Based on decoupling theory

Decoupling theory is effective to analyze the interdependence between variables and has been applied in environmental economics. However, most of the previous literature focus on “decoupling” and “recoupling” analysis, while rarely consider their driving factors. This study aims to explore the relationship between transportation CO₂ emissions and economic growth in Beijing from 1995 to 2014 by an extended Tapio elastic analysis, considering the contribution from industrial emission reduction, industrial energy saving, industrial operating efficiency, and industrial development. The entire decoupling state between transportation CO₂ emissions and economic growth changed with time. From 1995 to 2005, the decoupling relationship between transportation CO₂ emissions and economic growth exhibits a fluctuation among expansive negative decoupling, weak decoupling, and expansive coupling. Since decoupling elasticity values among industrial energy saving, industrial operating efficiency and industrial development were variably large and neutralized with each other, interaction of these decoupling elasticities may explain the fluctuation of the entire decoupling effect during this period. During the period from 2006 to 2008, the negative impact of industrial energy-saving elasticity overtook the positive one from industrial operating efficiency elasticity, which leads to worsening in the decoupling state between transportation CO₂ emissions and economic growth. The decoupling state was improved from expansive negative decoupling to weak decoupling after 2008, which can be attributed to policy-oriented practices supporting energy conservation.     

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.     

Testing the transport-induced environmental Kuznets curve hypothesis: The role of air and railway transport

The airline and railway industry contribute immensely to economic development, however, its role in environmental pollution requires attention. Here, this study builds on the theoretical pedigree of the environmental Kuznets curve (EKC) hypothesis to explore the contribution of the air and railway transportation sector and urbanization to the emission-growth argument. We utilized annual time-frequency data from 1995 to 2014 for a panel of top 10 air passenger carrier countries using robust panel estimators that control for cross-section dependence. The empirical analysis shows a positive significant relationship between emissions and economic growth, thus, economic growth is emission-embedded with limited green growth. The existence of the EKC phenomenon is affirmed for the investigated blocs — where economic growth is prioritized over environmental quality. Additional, while air transportation drives pollution, railway transportation and urbanization decline emission over the sampled period. The results underscore the need for clean and environmentally friendly energy sources for air sector operations.     

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.     

Tourism development and environmental degradation in the United States: evidence from wavelet-based analysis

The recent literatures indicate that the tourism development (TD) has significant influence over the environmental degradation of both high-tourist-arrival and low-tourist-arrival countries. This study investigates the empirical influence of TD on environmental degradation in a high-tourist-arrival economy (i.e. United States), using the wavelet transform framework. This new methodology enables the decomposition of time-series at different time–frequencies. In this study, we have used maximal overlap discrete wavelet transform (MODWT), wavelet covariance, wavelet correlation, continuous wavelet power spectrum, wavelet coherence spectrum and wavelet-based Granger causality analysis to analyse the relationship between TD and CO₂ emission in the United States by using the monthly data from the period of 1996(1) to 2015(3). Results indicate that TD is majorly having the positive influence over CE in short, medium and long run. We find the unidirectional influence of TD on CE in short run, medium and long run in the United States.     

Tourism development and economic growth in the Mediterranean countries: evidence from panel Granger causality tests

The aim of this study is to examine the relationship between tourism development and economic growth in the Mediterranean countries using the newly developed panel Granger causality tests for the 1995–2010 period. It is concluded that while there is bidirectional causal nexus between tourism development and economic growth for Portugal, unidirectional causal nexus from economic growth to tourism development is found for Spain, Italy, Tunisia, Cyprus, Croatia, Bulgaria and Greece. Therefore, the growth-led tourism hypothesis is supported in case of these seven countries. On the other hand, there is no causal relation for Malta and Egypt. The study finds evidence to support the tourism-led growth hypothesis for a group of panel in Mediterranean countries. The results of the overall study suggest that governments of Mediterranean countries should focus on economic policies to promote tourism as a potential source of economic growth.     

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.     

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.