Search Results (575)

PM_2.5 pollution has become one of the major environmental issues in Shandong Province in recent years. High concentrations of PM_2.5 not only reduce atmospheric visibility but also induce respiratory and cardiovascular diseases, and significantly increase health risks. Source apportionment of PM_2.5 is important for policy makers to determine control strategies. This study analyzed regional and sectoral PM_2.5 sources across 17 Shandong cities during the 2017–2018 winter heating season, which is selected because it is representative of severe air pollution with an average PM_2.5 of 65.75 μg/m³ and hourly peak exceeding 250 μg/m³. This air pollution episode aligned with key control policies, where seven major cities implemented steel capacity reduction and coal-to-gas/electric heating, as a baseline for evaluating emission reduction effectiveness. The particulate matter source apportionment technology in the Comprehensive Air Quality Model with extensions (CAMx) was applied to simulate the source contributions to PM_2.5 in 17 cities from different regions and sectors including industry, residence, transportation, and coal-burning power plants. The meteorological fields required for the CAMx model were generated using the Weather Research and Forecasting (WRF) model. The results showed that all cities besides Dezhou city in Shandong Province contributed PM_2.5 locally, varying from 39% to 53%. The emissions from Hebei province have a large impact on the PM_2.5 concentrations in Shandong Province. The non-local industrial and residential sources in Shandong Province accounted for the prominent proportion of local PM_2.5 in all cities. The contribution of non-local industrial sources to PM_2.5 in Heze City was up to 56.99%. As for Zibo City, the largest contribution of PM_2.5 was from non-local residential sources, around 56%. Additionally, the local industrial and residential sources in Jinan and Rizhao cities had relatively more contributions to the local PM_2.5 concentrations compared to the other cities in Shandong Province. Finally, the emission reduction effects were evaluated by applying different reduction ratios of local industrial and transportation sources, with decreases in PM_2.5 concentrations ranging from 0.2 to 26 µg/m³ in each city. Full article

Cropland fires are an important source of air pollution emissions and have a significant impact on regional air quality and human health. Although straw-burning ban policies have been implemented to mitigate emissions, the dynamics of PM_2.5 emissions from cropland fires under such stringent regulations are still not fully understood. This study utilizes PM_2.5 emission data from the Global Fire Assimilation System (GFAS), land-cover data from CLCD, and PM_2.5 concentration data from ChinaHighAirPollutants (CHAP) to examine the dynamic evolution of PM_2.5 emissions from cropland fires under straw-burning ban policies across China and to assess their environmental impacts. The results show that the 2013 Air Pollution Prevention and Control Action Plan initiated the development of provincial straw-burning ban policies. These policies resulted in a drastic reduction in PM_2.5 emissions from cropland fires in North China (NC), with a 65% decrease in 2022 compared to the 2012 peak. In contrast, a notable lagged effect was observed in Northeast China (NEC), where the increasing trend of PM_2.5 emissions was not reversed until 2017. By 2022, emissions in this region had declined by 53% and 45% compared to the 2015 peak and 2017 sub-peak, respectively. Moreover, significant regional differences were found in the environmental impacts of PM_2.5 emissions from cropland fires, with strong effects during summer in NC and during spring and autumn in NEC. This study provides empirical support for understanding the environmental impacts of cropland fires in key regions of China and offers critical insights to inform and refine related pollution control policies. Full article

This study evaluates the effectiveness of air pollution control measures in Xi’an, China, by investigating long-term changes in the concentrations, optical properties, and sources of black carbon (BC) and brown carbon (BrC). Wintertime observations of PM_2.5 carbonaceous aerosols were conducted over multiple years using a continuous Aethalometer. The data were analyzed using advanced aethalometer models, potential source contribution function (PSCF) analysis, and generalized additive models (GAMs) to deconstruct emission sources and formation pathways. Our results revealed a significant decrease in the mass concentration and light absorption coefficient of BC (b_abs-BC) between the earlier and later study periods, indicating successful emission reductions. In contrast, the light absorption from BrC (b_abs-BrC) remained relatively stable, suggesting persistent and distinct emission sources. Source apportionment analysis demonstrated a temporal shift in dominant regional influences, from biomass burning in the initial years to coal combustion in later years. In addition, GAMs showed that the primary driver for liquid fuel-derived BC transitioned from gasoline to diesel vehicle emissions. For solid fuels, residential coal combustion consistently contributed over 50% of BC, highlighting that improvements in coal combustion technology were effective in reducing BC emissions. Furthermore, a substantial fraction of BrC was increased, with nocturnal peaks associated with high relative humidity, emphasizing the aqueous-phase formation influences. Collectively, these findings demonstrated that although certain control strategies successfully mitigated BC, the persistent challenge of BrC pollution necessitates targeted measures addressing secondary formation and primary fossil fuel sources. Full article

Air pollution from lignite combustion represents a major environmental and public health concern, particularly for cardiovascular disease. This study investigated the relationship between ambient air pollution and hospital admissions for Acute Coronary Syndromes (ACS) and Atrial Fibrillation (AF) in Western Macedonia, Greece—a region historically dominated by lignite mining and power generation. Air quality data for PM₁₀, SO₂, and NO_x from 2011–2014 and 2021 were analyzed alongside hospital admission records from four regional hospitals (Kozani, Ptolemaida, Florina, Grevena). Spatial analyses revealed significantly higher pollutant concentrations and cardiovascular admissions in high-exposure areas near power plants compared with the control area. Temporal analyses demonstrated a pronounced decline in pollutant levels between 2014 and 2021, coinciding with lignite phase-out and accompanied by a marked reduction in ACS and AF hospitalizations, particularly in the high-exposure areas of Ptolemaida and Florina. Correlation analyses indicated modest but significant positive associations between monthly pollutant concentrations and cardiovascular admissions. These findings provide real-world evidence that reductions in air pollution following lignite decommissioning were associated with improved cardiovascular outcomes. The study underscores the medical importance of air quality improvement and highlights emission reduction as a critical strategy for cardiovascular disease prevention in transitioning energy regions. Full article

The study of energy needs in rural areas continues to be an active field of research. Although numerous gaps hinder the achievement of a sustainable energy transition in these areas, it is necessary to develop comprehensive strategies that integrate local participation with the implementation of efficient and appropriate energy technologies. This research analyzes local energy needs using a community participatory approach and considers four main stages, including a participatory diagnosis at the community level to identify energy needs, defining priority energy needs from the community’s viewpoint, estimating a baseline of the identified needs, their economic costs, and environmental impacts, constructing a scenario with a 20-year projection, and the benefits of implementing more efficient technologies. The results show that 98.9% of energy is destined for residential needs, 0.6% for community needs, and 0.5% for productive needs, and the economic expenditure follows the same hierarchy, while total emissions are estimated annually at just over 30,000 tCO_2e and 3 tPM_2.5. With the proposed scenario, at the end of year 20, a reduction in consumption of just over 200 TJ is estimated, together with present value savings of USD 490,000, and a decrease in emissions of approximately 27,000 tCO_2e and 2.7 tPM_2.5. This proposal is expected to contribute to encouraging research with broad community participation and to the formulation of strategies that enable a sustainable energy transition in rural contexts. Full article

Family Allotment Gardens (FAGs) represent key components of urban cooling and air-purification systems. However, research has mainly focused on their social roles and on their contributions to food production. This study quantified the capacity of FAGs in Warsaw (Poland) to provide two key ecosystem services at distances up to 300 m from their boundaries: air-pollution filtration and microclimate regulation. Measurements of particulate matter (PM1, PM2.5, PM10), air temperature and relative humidity were conducted along transects inside and outside three allotment complexes in autumn 2023, a period characterised by increased traffic emissions and elevated particulate levels. The results show a moderate but significant reduction in PM concentrations inside gardens (by about 2 µg/m³; r = 0.22–0.29) and slightly higher humidity (by 2.1%; r = −0.34). The cooling effect was weak (<0.3 °C; r = 0.06), indicating a limited spatial range under autumn conditions, though selected transects exhibited stronger local effects. The results confirm that FAGs can contribute to air purification and local climate regulation, but their effectiveness depends on vegetation structure and urban context. Strengthening their role requires integration with green-infrastructure planning and emission-reduction practices within gardens. FAGs, beyond their recreational and productive value, should be recognised as active components of urban adaptation strategies. Full article

Air pollution is a growing environmental issue in densely populated urban areas worldwide. Rapid population growth and the consequent increase in energy demand, emissions from industrial activities and vehicular traffic, and the reduction in vegetation cover have in recent years led to increasing concerns about quality of life, especially due to serious health problems associated with respiratory diseases. This study focuses on air quality in the city of Turin in north-western Italy. Continuous one-year monitoring, which collected approximately two million georeferenced data points, was possible using specific devices—palm-sized, wearable, and commercially available sensors—in different parts of the city. This enabled the assessment of the geographical and seasonal distributions of the most commonly studied air pollutants, namely particulate matter (PM) of three size fractions, nitrogen dioxide (NO₂), and total volatile organic compounds (TVOCs). The results highlight that the north-western zone and the urban centre are the most polluted areas. In particular, seasonal variations suggest that space heating and cooling systems, together with industrial activities, are the main contributors, more so than vehicular traffic. In this context, handheld devices in an IoT context can provide a reliable description of the spatial and temporal distribution of common air pollutants. Full article

Atmospheric fine particles (PM_2.5, aerodynamic diameter ≤ 2.5 µm) have a serious effect on human health. This study combined concentration weighted trajectory (CWT) analysis with the HYSPLIT trajectory ensemble (Ens-HYSPLIT-CWT), to separate the sources of PM_2.5 transported to Beijing, and further investigate the effect of PM_2.5 originated from different sources on human health. We found that north region air masses usually come with clean events under the blessing of meteorological conditions, combined with the clean air mass transported from the north, as high wind speed near the surface promotes the horizontal diffusion of pollutants. Additionally, north region air masses contribute to the decrease in aerosol optical depth (AOD) at Beijing and surrounding areas, with AF (daily attributable fraction associated with short-term PM_2.5 exposure) values of Beijing only at 0.14. During the study period (from January to March 2024), south region air masses usually come with high PM_2.5 values, which is correlated to the meteorological conditions and pollutant spatial distribution. The air masses coming from the south region contain high temperature and relative humidity (RH), promoting the occurrence of high pollution events. AOD spatial distribution observed from satellites showed that except for the dominance of north region air mass sources, the south region presents high AOD values, further resulting in the highest AF value of 0.75 obtained at Beijing, which is 5 times higher than the north region’s dominant AF mean value. It is worth noting that the air mass originated from the east region, which originally contributed relatively clean air masses before emission reduction, increased its contribution to air mass pollution after emission reduction due to the decrease in pollution concentration in other regions. As a result, the mean PM_2.5 in this source area was second only to south region air masses and local emission sources, and the AF value even exceeded local emissions, second only to south region air mass sources, reaching 0.5. This result emphasizes that in future pollution control policy adjustments and research on human health, attention needs to be paid to the contribution of eastward air masses. Full article

Air pollutants and greenhouse gases share common sources, primarily originating from human activities such as energy utilization, thus presenting significant potential for synergistic control. Isolated consideration of solutions for either pollution mitigation or carbon reduction increases the unit cost of environmental governance and leads to inconsistencies and overlapping effects in policy measures. This study takes Chengdu, a low-carbon pilot city in China, as a case study. Based on clarifying the characteristics of regional air pollutant emissions and carbon emissions from energy consumption, it empirically investigates the synergistic variation in carbon emissions from diverse socioeconomic industries and multiple air pollutant emissions. The empirical results reveal the following: (1) during the research period, Chengdu’s air quality excellence rate demonstrated continuous improvement. Meanwhile, the carbon emissions from energy consumption exhibited a three-phase developmental pattern. The driving forces of growth had shifted from traditional high-energy-consuming industries to advanced manufacturing, urban basic energy demands, and energy extraction industries serving national strategies. (2) The synergistic reduction in carbon emissions with PM₁₀ and PM_2.5 reached relatively high levels from 2016 to 2019, followed by fluctuations due to the impact of the COVID-19 pandemic. The synergistic reduction between carbon emissions and SO₂ exhibited considerable volatility. The electrification trend in transportation significantly promoted the synergistic reduction in carbon emissions and NO₂ emissions. Due to the fact that O₃ is a secondary pollutant with complex sources, achieving synergistic governance with carbon emissions proved more challenging. As a result of technological limitations, the synergistic reduction in carbon emissions and CO gradually exhibited a trend of diminishing marginal effects. The synergistic reduction effects between industry-specific carbon emissions and overall air pollutant emissions can be divided into five categories: sustained high-efficiency, generally stable, fluctuating, sudden-decline, and persistently low. Full article

Air pollution constitutes a major environmental determinant of cardiovascular morbidity and mortality worldwide. Western Macedonia, Greece, has historically hosted the largest lignite mining and combustion complex in Southeastern Europe, creating a unique exposure environment. This study investigates the relationship between air pollutant concentrations and cardiovascular hospital admissions over a ten-year period in this lignite-dependent region. Daily concentrations of particulate matter (PM₁₀), sulfur dioxide (SO₂), nitric oxide (NO), nitrogen dioxide (NO₂), and total nitrogen oxides (NO_x) were collected from regional monitoring stations for the winters of 2011–2021, while corresponding daily cardiovascular hospital admissions were obtained from the regional hospitals of Kozani, Ptolemaida, Florina, and Grevena. Spearman’s rank correlations and Friedman’s non-parametric tests were applied to assess temporal and spatial associations between pollutant levels and hospital admissions. A marked decline in air pollutant concentrations, particularly PM₁₀ and SO₂, was observed across the decade, coinciding with a significant reduction in cardiovascular hospitalizations. Specifically, PM₁₀ levels fell from ~75 μg/m³ to ~30 μg/m³ in Florina and from ~53 μg/m³ to ~11 μg/m³ in Ptolemaida, while SO₂ concentrations decreased by more than 90% across all sites. Cardiovascular admissions declined by 20–40% depending on the region over the same period. Significant but modest positive correlations were detected between PM₁₀ and admissions in Florina (ρ = 0.138, p = 0.017), SO₂ in Ptolemaida (ρ = 0.122, p = 0.034), and NO₂ in Kozani (ρ = 0.115, p = 0.045). Regions located near lignite combustion sites consistently exhibited higher pollutant levels and hospitalization rates. The study provides quantitative evidence linking air pollution from lignite combustion to adverse cardiovascular outcomes. The parallel decline in both pollution levels and hospital admissions underscores the cardiovascular benefits of emission reduction and the ongoing energy transition in Western Macedonia. Continuous air quality monitoring and preventive public health measures remain essential for safeguarding cardiovascular health in former coal-based regions. Full article

In the context of pavement management systems (PMSs), overloaded trucks impose severe economic and environmental burdens by accelerating pavement deterioration and increasing greenhouse gas (GHG) emissions. Existing research on Weigh-in-Motion (WIM) placement has rarely incorporated environmental impacts, particularly greenhouse gas (GHG) emissions, into the decision-making process. Instead, most studies have focused on infrastructure damage and have paid limited attention to how enforcement interacts with driver evasion behavior and schedule-related constraints. To address this gap, this study develops a bi-level optimization framework that simultaneously minimizes PMS costs, travel costs, and environmental (GHG) costs. The upper-level problem represents the total social cost minimization, while the lower-level problem models drivers’ routes and demand shift. The framework endogenously captures utility-based demand shifts, allowing overloaded drivers to switch to legal operations when enforcement and schedule-related constraints outweigh overloading benefits. A numerical study using the Sioux Falls network demonstrates that dual WIM installations significantly outperform single configurations, achieving network-wide cost reductions of up to 1.5% compared to 0.4%. Notably, PMS costs for overloaded trucks decreased by nearly 60%, confirming the effectiveness of strategic enforcement. Ultimately, this study contributes a unified decision-support tool that reframes WIM enforcement from a passive control measure into a proactive strategy for sustainable freight management. Full article

Climate change (CC) and air pollution are closely interlinked environmental challenges that significantly affect human health and quality of life, especially in urban and industrialized regions. This study conducted a comprehensive investigation on how future climate scenarios may affect air quality and related human impacts, using a Southern European country (Portugal) for illustration. The study employed the most up-to-date future climate projections (Shared Socioeconomic Pathways—SSP) that were dynamically downscaled for Portugal. High-resolution simulations were carried out using the Weather Research & Forecasting (WRF) model, providing data for relevant meteorological variables that most affect air quality, for three future climate scenarios: fossil-fueled development (SSP5-8.5), regional inequality (SSP3-7.0), and a middle-of-the-road future (SSP2-4.5). Current and future air quality was simulated with the CHIMERE chemical transport model driven by WRF downscaled data and future emissions from the SSP v2.0 database. Results show that CC will impact nitrogen oxides (NO₂), ozone (O₃), and particulate matter (PM) concentrations over Portugal, with only agricultural emissions increasing in all scenarios. PM and NO₂ will decrease in urban areas, over the short and long term, mainly for more conservative scenarios (SSP2-4.5 and SSP3-7.0), while O₃ will increase over mainland Portugal (except for coastal/urban areas). Regarding human health, premature deaths are expected to be highest in urban areas, with reductions projected for NO₂ and PM_2.5 under SSP2-4.5 and increases in O₃-related mortality under SSP5-8.5. Overall, SSP2-4.5 presents the most sustainable outcomes, highlighting the importance of integrating air quality management and health impact assessments into climate adaptation strategies to promote long-term environmental sustainability in southern Europe, consistent with the United Nations Sustainable Development Goals (SDGs). Full article

This study investigates the impact of high-resolution spatiotemporal profiles of road transport emissions on urban air quality simulations for Thessaloniki, Greece. Dynamic spatiotemporal emission profiles were developed based on real vehicle speed data and implemented in an integrated air quality modeling system to improve the representation of temporal and spatial traffic activity patterns. The new profiles captured the variability of emissions across hours, days, and months, reflecting differences in congestion intensity and seasonal mobility behavior. Zero-out air quality simulations, in which road transport emissions were entirely removed from the model domain, revealed that road transport is a dominant source of urban air pollution, contributing by up to 47 μg/m³ to daily NO₂ and up to 15 μg/m³ to daily PM_2.5 concentrations during winter, while remaining significant in summer. The speed-based spatiotemporal profiles affected NO and NO₂ concentrations by up to +20 μg/m³ and +3.8 μg/m³, respectively, during the rush hours in winter. The use of dynamic spatiotemporal profiles improved model performance with a maximum daily BIAS reduction of –5 μg/m³ for NO and an increase in the index of agreement of up to 0.13 during the warm period, demonstrating a more accurate representation of traffic-related air pollution dynamics. Improvements for PM_2.5 were smaller but consistent across most monitoring sites. Overall, the study demonstrated that incorporating detailed traffic-derived spatiotemporal profiles enhances the accuracy of urban air quality simulations. The proposed approach provides valuable input for municipal action plans, supporting the design of effective traffic management and emission reduction strategies tailored to local conditions. Full article

The first extensive Bus Rapid Transit (BRT) system in the Philippines, the EDSA Busway, was put into place as a result of Metro Manila’s ongoing traffic congestion. This study uses an integrated framework that combines cost–benefit analysis (CBA), commuter perception survey, and traffic simulation to assess its economic, social, and environmental implications. The operational viability and traffic impact of the planned Magallanes BRT station were evaluated through simulation using PTV VISSIM. A total of 385 commuters participated in a survey measuring their impressions of safety, accessibility, and satisfaction using a four-point Likert scale. The Busway’s excellent economic feasibility was confirmed by the CBA results, which showed a Benefit–Cost Ratio (BCR) of 15.38 and a Net Present Value (NPV) of ₱778.64 billion. Results from the simulation showed a 24% decrease in PM₂ emissions, a 75% increase in throughput, and a 64% reduction in bus trip time. According to survey results, 61% of commuters said accessibility had improved and 62% said travel satisfaction had increased. The study supports the EDSA Busway’s status as a feasible model for future BRT expansion in Metro Manila and other emerging metropolitan regions by showing how it greatly improves environmental sustainability and mobility efficiency. Full article

Accurate assessment of vehicular air pollution in arid urban environments remains a challenge because standard emission models often overlook localized influences such as climate-driven dust resuspension and urban canyon effects. This study develops an enhanced modeling framework that integrates critical regional parameters into established algorithms to improve estimates of traffic-related emissions, including PM₁₀, PM₂.₅, CO, and NO₂. The US EPA’s AP-42 algorithm was modified to incorporate a novel highway width-to-building height ratio (I/H) and a climate-driven dynamic silt loading model derived from satellite data, while the European EEA algorithm was refined by introducing an explicit fuel density correction (ρ). The framework was applied and validated on two representative highways in Jordan—an industrial corridor and an urban-commercial artery—using continuous sensor-based measurements. Results indicate substantial improvement in predictive performance, with reductions of 60–77% in normalized difference for particulate matter and 72% for CO. The model successfully distinguished between emission regimes, capturing a seasonal silt-loading peak of approximately 17.5 g/m² during autumn at the industrial site, compared to more stable, traffic-dominated emissions along the urban corridor. Although NO₂ performance showed modest gains (4–40%) due to complex photochemical processes, the overall framework proved to be a robust and reliable tool for air quality assessment in arid cities. This adaptable approach provides a foundation for targeted air pollution management, and future work will integrate real-time dispersion dynamics and photochemical modules to better capture secondary pollutant formation. Full article