Spatial disaggregation of traffic emission inventories in large cities using simplified top-down methods

Simple, inexpensive and accurate methods for assessing the spatial distribution of traffic emissions are badly needed for the environmental management in South American cities. In this study, various spatial disaggregation methods of traffic emissions of carbon monoxide are presented and evaluated for a large city (Santiago de Chile). Previous methods have used a simplified road network as a proxy for deriving spatial patterns of emissions. However, these approaches resulted in underestimation of emissions in urban centers, industrial zones and highly loaded roads, as well as overestimation in residential zones. Here we modify these methods by adding data correlated with the emissions (e.g. traffic counts, vehicles mean speed, road capacity) solving partially or completely the indicated problems. After an accuracy-simplicity analysis two methodologies stand out over the others: using traffic count classification and using a land use map, both combined with a simplified road network. B

The applicability of non-local LCI data for LCA

This study evaluated how applicable European Life Cycle Inventory (LCI) data are to assessing the environmental impacts of the life cycle of Brazilian triple superphosphate (TSP). The LCI data used for the comparison were local Brazilian LCI data, European LCI data in its original version from the ecoinvent database and a modified version of the European LCI data, which had been adapted to better account for the Brazilian situation. We compared the three established datasets at the level of the inventory as well as for their environmental impacts, i.e. at the level of Life Cycle Environmental Assessment (LCIA). The analysis showed that the European LCIs (both the original and the modified ones) considered a broader spectrum of background processes and environmental flows (inputs and outputs). Nevertheless, TSP production had in all three cases similar values for the consumption of the main raw materials. The LCIA results obtained for the datasets showed important differences as well. Therefore we concluded that the European data in general lead to much higher environmental impacts than the Brazilian data. The differences between the LCIA results obtained with the Brazilian and the European data can be basically explained by the methodological differences underlying the data. The small differences at the LCI level for selected inputs and outputs between the Brazilian and the European LCIs from ecoinvent indicate that the latter can be regarded as applicable for characterizing the Brazilian TSP

Modelling uncertainty in the sustainability of intelligent transport systems for highways using probabilistic data fusion.

The implementation of ITS to increase the efficiency of saturated highways has become increasingly prevalent. It is a high level objective for many international governments and operators that highways should be managed in a way that is both sustainable i.e. environmental, social and economically sound and supportive of a Low-Carbon-Energy Future. Some clarity is therefore needed to understand how Intelligent Transport Systems perform within the constraints of that objective. The paper describes the development of performance criteria that reflect the contributions of Information Communication Technology (ICT) emissions, vehicle emissions and the embedded carbon within the physical transport infrastructure that typically comprises one type of Intelligent Transport System i.e. Active Traffic Management – a scheme that is used to reduce inter-urban congestion. The performance criteria form part of a new framework methodology ‘EnvFUSION’ (Environmental Fusion for ITS) outlined here. This is illustrated using a case study where environmental performance and pollution baselines (collected from independent experts, academic, governmental sources and suppliers) are processed using an attributional Lifecycle Assessment tool. The tool assesses the production and operational processes of the physical infrastructure of Active Traffic Management using inputs from the ‘Ecoinvent’ database. The ICT component (responsible for data links) is assessed using direct observation, whilst vehicle emissions are estimated using data from a National Atmospheric Emissions Laboratory. Analytical Hierarchy Process and Dempster–Shafer theory are used to create a prioritised performance hierarchy: the Intelligent Transport Sustainability Index, which includes weighted criteria based on stakeholder expertise. A synthesis of the individual criteria is then used to reflect the overall performance of the Active Traffic Management scheme in terms of sustainability (low-carbon-energy and socio-economic) objectives

Sustainability assessment approaches for Intelligent Transport Systems: The state of the art

The appraisal of ITS systems has become increasingly important in order to capture their full range of potential impacts. The goal of this paper is therefore to assess the appropriateness of conventional transport appraisal models and tools for this task, particularly in reflecting the environmental and socio-economic impacts of ITS. These include the most common Environmental Systems Analysis tools (ESAT), which incorporate international standards and are of considerable importance in indicating sustainability. A review of how emerging methods relate to the goal of a successful transition to a low carbon future is reported, based on the literature. The appraisal of ITS is inherently uncertain due to the decentralised nature of Information Communication Technology (ICT), therefore a range of methods to capture this aspect are reviewed. The models, weights and methods are analysed concerning their ability to estimate sustainability performance, given the numerous configurations of ubiquitous technology that may comprise ITS services. Weighting methods are important in reflecting perceptions of how sustainability should be assessed. These can be incorporated by identifying, classifying and selecting one or more ESAT's based upon their suitability for a particular application. Finally, recommendations are given on which tools can be integrated to more comprehensively reflect the performance of ITS