This paper advances existing research on both the geographies of fashion and the geographies of waste, utilising their shared interests in commodity biography. Empirically, it documents the use of ...textile waste from export-oriented garment factories in the peri-urban areas of Phnom Penh, Cambodia as fuel for nearby brick-kilns supplying the city's booming construction sector. Interviews and documentary photography present the forms of living, labour and harm at both the brick-kilns and the garment dump from which the textile waste is sourced. Substantively, the paper argues for the consideration of preconsumer garment waste to complement the dominant preoccupation with postconsumer waste and reuse. Conceptually, the paper argues for geographical biographies of commodity culture that are attentive to things' material dynamics of becoming, unbecoming and transformation across spaces, sectors and material forms: that is, to their 'patch geographies'.
Urban heat waves (UHWs) are strongly associated with socioeconomic impacts. Here, we use an urban climate emulator combined with large ensemble global climate simulations to show that, at the urban ...scale a large proportion of the variability results from the model structural uncertainty in projecting UHWs in the coming decades under climate change. Omission of this uncertainty would considerably underestimate the risk of UHW. Results show that, for cities in four high-stake regions - the Great Lakes of North America, Southern Europe, Central India, and North China - a virtually unlikely (0.01% probability) UHW projected by single-model ensembles is estimated by our model with probabilities of 23.73%, 4.24%, 1.56%, and 14.76% respectively in 2061-2070 under a high-emission scenario. Our findings suggest that for urban-scale extremes, policymakers and stakeholders will have to plan for larger uncertainties than what a single model predicts if decisions are informed based on urban climate simulations.
Assessment of the global burden of disease is based on epidemiological cohort studies that connect premature mortality to a wide range of causes, including the long-term health impacts of ozone and ...fine particulate matter with a diameter smaller than 2.5 micrometres (PM2.5). It has proved difficult to quantify premature mortality related to air pollution, notably in regions where air quality is not monitored, and also because the toxicity of particles from various sources may vary. Here we use a global atmospheric chemistry model to investigate the link between premature mortality and seven emission source categories in urban and rural environments. In accord with the global burden of disease for 2010 (ref. 5), we calculate that outdoor air pollution, mostly by PM2.5, leads to 3.3 (95 per cent confidence interval 1.61-4.81) million premature deaths per year worldwide, predominantly in Asia. We primarily assume that all particles are equally toxic, but also include a sensitivity study that accounts for differential toxicity. We find that emissions from residential energy use such as heating and cooking, prevalent in India and China, have the largest impact on premature mortality globally, being even more dominant if carbonaceous particles are assumed to be most toxic. Whereas in much of the USA and in a few other countries emissions from traffic and power generation are important, in eastern USA, Europe, Russia and East Asia agricultural emissions make the largest relative contribution to PM2.5, with the estimate of overall health impact depending on assumptions regarding particle toxicity. Model projections based on a business-as-usual emission scenario indicate that the contribution of outdoor air pollution to premature mortality could double by 2050.
Air pollution has become a major threat to human health in the last decades, with an increase of acute air pollution episodes in many cities worldwide. Source apportionment modelling provides ...valuable information on the contribution from different emission source sectors and source regions to distinct air pollutants concentrations. In this study, the CAMx model, with its PSAT tool, was applied to quantify the contribution of multiple source areas, categories and pollutant types to ambient air pollution, namely to PM and NO2 concentrations, over six European urban areas: Bristol (United Kingdom), Amsterdam (The Netherlands), Ljubljana (Slovenia), Liguria Region (Italy), Sosnowiec (Poland) and Aveiro Region (Portugal). Results indicate overall higher annual NO2 and PM concentrations located in the urban centres of the case studies. A comparison between the different areas showed that Liguria is the region with highest NO2 annual mean concentrations, while Ljubljana, Liguria Region and Sosnowiec are the case studies with the highest PM annual mean concentrations. The annual average contributions denote a major influence from road transport to NO2 concentrations, with up to 50%, except in Aveiro region, where road transport presents a lower contribution to NO2 concentrations, and the greatest contributor is the industrial combustion and processes sector with 45%. These results indicate a negligible contribution of the transboundary transport to NO2 concentrations, highlighting the relevance of local sources, while for PM concentrations the transboundary transport is the major contributor. The results highlight the relevance of long-range transport of PM across Europe. The transboundary transport reduces its importance during winter, when residential and commercial combustion increases its contribution. In the case of the Aveiro region, the industrial combustion and processes sector also plays an important contribution to PM concentrations.
•Quantification of source contribution to air pollution in six European urban areas.•Air pollution findings that recognize the heterogeneity of each case study.•Major influence from road transport to NO2 concentrations, in almost all cities.•Relevance of long-range transport of PM across Europe.
To this end, greater attention needs to be paid to emerging technologies, such as the internet of things, cognitive computing, advanced analytics and business intelligence, 5G networks, anticipatory ...and context-aware computing and advanced distributed data warehouse platforms. ...smart cities provide a context for a multidisciplinary discussion related to the value-added proposition of several leading-edge technologies, including immersive technologies, virtual and augmented reality (Lytras et al., 2016), wearable technologies, cloud computing, data science, big-data insights, social networks (Lytras and Mathkour, 2017), Web applications and internet technologies (Lytras et al., 2017; Wu et al., 2018). According to the Digital Agenda for Europe, the smart cities concept means smarter urban transport networks, upgraded water supply and waste-disposal facilities, along with more efficient ways to light and heat buildings. Each dataset has been extracted from laboratory-controlled scenarios carried out with up to 400 people walking through a corridor whose configuration changed in the form of the amplitude of its entrance doors and the amplitude of its exit doors from one experiment to another. ...each dataset contained different groups of coordinates that compose pedestrian trajectories.
Urban streams commonly express degraded physical, chemical, and biological conditions that have been collectively termed the “urban stream syndrome”. The description of the syndrome highlights the ...broad similarities among these streams relative to their less-impaired counterparts. Awareness of these commonalities has fostered rapid improvements in the management of urban stormwater for the protection of downstream watercourses, but the focus on the similarities among urban streams has obscured meaningful differences among them. Key drivers of stream responses to urbanization can vary greatly among climatological and physiographic regions of the globe, and the differences can be manifested in individual stream channels even through the homogenizing veneer of urban development. We provide examples of differences in natural hydrologic and geologic settings (within similar regions) that can result in different mechanisms of stream ecosystem response to urbanization and, as such, should lead to different management approaches. The idea that all urban streams can be cured using the same treatment is simplistic, but overemphasizing the tremendous differences among natural (or human-altered) systems also can paralyze management. Thoughtful integration of work that recognizes the commonalities of the urban stream syndrome across the globe has benefitted urban stream management. Now we call for a more nuanced understanding of the regional, subregional, and local attributes of any given urban stream and its watershed to advance the physical, chemical, and ecological recovery of these systems.
Urbanization, a dominant global demographic trend, leads to various changes in environments (e.g., atmospheric CO₂ increase, urban heat island). Cities experience global change decades ahead of other ...systems so that they are natural laboratories for studying responses of other nonurban biological ecosystems to future global change. However, the impacts of urbanization on vegetation growth are not well understood. Here, we developed a general conceptual framework for quantifying the impacts of urbanization on vegetation growth and applied it in 32 Chinese cities. Results indicated that vegetation growth, as surrogated by satellite-observed vegetation index, decreased along urban intensity across all cities. At the same time, vegetation growth was enhanced at 85% of the places along the intensity gradient, and the relative enhancement increased with urban intensity. This growth enhancement offset about 40% of direct loss of vegetation productivity caused by replacing productive vegetated surfaces with nonproductive impervious surfaces. In light of current and previous field studies, we conclude that vegetation growth enhancement is prevalent in urban settings. Urban environments do provide ideal natural laboratories to observe biological responses to environmental changes that are difficult to mimic in manipulative experiments. However, one should be careful in extrapolating the finding to nonurban environments because urban vegetation is usually intensively managed, and attribution of the responses to diverse driving forces will be challenging but must be pursued.
Nature-based solutions (NBS) are increasingly applied to guide the design of resilient landscapes and cities to enable them to reach economic development goals with beneficial outcomes for the ...environment and society. The NBS concept is closely related to other concepts including sustainability, resilience, ecosystem services, coupled human and environment, and green (blue) infrastructure; however, NBS represent a more efficient and cost-effective approach to development than traditional approaches. The European Commission is actively engaged in investing in NBS as a driver in developing ecosystem services-based approaches throughout Europe and the world. The pool of knowledge and expertise presented in this Special Issue of Environmental Research highlights the applications of NBS as ‘living’ and adaptable tools to boost the capacity of landscapes and cities to face today’s critical environmental, economic and societal challenges. Based on the literature and papers of this Special Issue, we propose five specific challenges for the future of NBS.
The past decade has seen a rapid penetration of electric vehicles (EVs) as more and more logistics and transportation companies start to deploy electric vehicles (EVs) for service provision. In order ...to model the operations of a commercial EV fleet, we utilize the EV routing problem with time windows (EVRPTW). In this paper, we propose an end-to-end deep reinforcement learning framework to solve the EVRPTW. In particular, we develop an attention model incorporating the pointer network and a graph embedding layer to parameterize a stochastic policy for solving the EVRPTW. The model is then trained using policy gradient with rollout baseline. Our numerical studies show that the proposed model is able to efficiently solve EVRPTW instances of large sizes that are not solvable with current existing approaches.
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