Typhoons could influence air quality via multiple chemical and physical process and has attracted much scientific attention. A typical typhoon, In-Fa, passed through Yangtze River Delta (YRD) and ...Jing-Jin-Ji (JJJ) after it made a landfall in China. Under such influences, two city clusters both experienced high ozone (O3) concentrations, with JJJ about 5 days earlier than YRD. Data from several environmental monitoring sites and three regional sites indicated that cross-regional transport and biogenic emissions both played an important role in O3 formation. During the typhoon process, O3 precursors were first transported from YRD and its surrounding areas to JJJ due to the summer monsoon. After that, air masses from northern China returned to YRD due to the peripheral winds of the typhoon. High O3 was concentrated in downwind regions, causing fast secondary formation. The peripheral winds and downdrafts of typhoon led to high temperature and stagnant weather, favorable for biogenic emissions. Observed isoprene concentration was doubled. The ratio of isoprene to VOCs also increased by around 5%. The modeling results showed the contribution of BVOCs to O3 could reach 10 ppb in JJJ when the typhoon made its landfall in YRD. When the typhoon moved to JJJ, the cross-transport of air masses from northern China to YRD contributed half of biogenic-emission-related O3. Our research extends the knowledge into the importance of biogenic emissions to O3 and cross-regional transport during a typhoon process.
•High O3 concentrations occurred in two city clusters, JJJ and YRD, during a typhoon process.•Cross-regional transport connected pollutants and precursors in two city clusters.•Isoprene was enhanced in peripheral areas as the typhoon moved, contributing to O3 in downwind areas.
The realities of the modern city dictate the conditions for the expansion of human habitats. A number of industrial buildings erected in the last century occupies large territories, often in the ...center of cities. This causes environmental and aesthetic problems. In the historical centers of large cities of Kazakhstan, the problem of industrial zones renovation is especial urgent. At the same time, it is necessary to consider the economic feasibility of such activities, their profitability, and ways to preserve the architectural ensemble of historical buildings. Moreover, one of the fundamental factors is the psychological component, that is, the need to preserver the history of industrial buildings. At the same time, it is necessary to modernize and renovate enterprises, move production out of the city, and preserve existing buildings, changing their function to a more relevant one, while forming a unique ecosystem. To resolve this issue, a government program of Kazakhstan was considered, which in every possible way contributes to the renovation policy. However, for its optimal implementation, it is necessary to consider economic aspects, select the best ways and methods of renovation, and also study foreign experience, critically compare it with domestic renovation projects and formulate recommendations necessary for the renovation of industrial buildings.
A growing body of research has shown that barriers in the urban environment can be disabling by reducing the ability of older people to manage independently in the community, but also because they ...can negatively affect health by limiting the possibilities to move outside the home. In this study, we ask how obstacles in the urban environment are associated with the need for help to go to places in the community. To respond to this question, we used the Annual Household Survey of the City of Buenos Aires, Argentina 2018, which had a specific questionnaire for people with disabilities. From this sample, we selected adults aged 65 years or older with difficulties in at least one of six domains: vision; hearing; upper and lower body mobility; cognition; self-care; and communication. The final sample consisted of 513 persons (weighted = 109,316). First, we conducted a principal component analysis identifying three factors from variables of obstacles to access and use the urban environment: transportation; outdoor spaces; and information. Second, through a logistic regression model, we observed a direct relationship between these factors and the need for help to move in the community, controlling for sociodemographic characteristics, health status, and number of disabilities. This paper provides evidence on the significance of improving urban spaces to reduce dependent mobility. In Latin America, cities still face many challenges in becoming more age-friendly.
The loss of green spaces in urbanized areas has triggered a potential thermal risk in the urban environment. While the existing literature has investigated the direct relationship between urban ...temperatures and health risks, little is known about causal relationships among key components of urban sustainability and health risks, through a pathway involving urban temperature. This study examined the multiple connections between urbanized land use, urban greenery, urban temperatures and health risks in Harris County, Texas. The census tract-level health data from the 500 Cities Project (Centers for Disease Control and Prevention) is used for analysis. Structural equation model analyses showed that the urban temperature played a mediating role in associations between urbanized land use, urban greenery and health risk. Urban vegetation is associated with a decrease in health risks, while urban land use has associations with an increase in health risks. Findings suggest that proactive policies tailored to provide rich urban greenery in a neighborhood can alleviate urban land use effects on health risks.
Nearly 3 billion additional urban dwellers are forecasted by 2050, an unprecedented wave of urban growth. While cities struggle to provide water to these new residents, they will also face equally ...unprecedented hydrologic changes due to global climate change. Here we use a detailed hydrologic model, demographic projections, and climate change scenarios to estimate per-capita water availability for major cities in the developing world, where urban growth is the fastest. We estimate the amount of water physically available near cities and do not account for problems with adequate water delivery or quality. Modeled results show that currently 150 million people live in cities with perennial water shortage, defined as having less than 100 L per person per day of sustainable surface and groundwater flow within their urban extent. By 2050, demographic growth will increase this figure to almost 1 billion people. Climate change will cause water shortage for an additional 100 million urbanites. Freshwater ecosystems in river basins with large populations of urbanites with insufficient water will likely experience flows insufficient to maintain ecological process. Freshwater fish populations will likely be impacted, an issue of special importance in regions such as India's Western Ghats, where there is both rapid urbanization and high levels of fish endemism. Cities in certain regions will struggle to find enough water for the needs of their residents and will need significant investment if they are to secure adequate water supplies and safeguard functioning freshwater ecosystems for future generations.
•Future energy demands for cooling will be dramatically increased.•Wide deployment of renewables in cities should be a top priority.•The installation of renewables in district level reduces ...transmission infrastructure.•Micro renewables can be easily integrated in the building fabric.•Smart grids are the key for managing effectively the energy production and demand.
Urban heat island and global warming increase the urban ambient temperature. Increased temperatures have a tremendous effect on the energy demand for cooling, with a great impact on peak and total electricity demand.
Renewable technologies in the urban environment have been widely regarded as an increasingly important solution to deal with the climate change challenges and energy security. Significant effort is performed in the integration of photovoltaic panels (PV) and micro turbines in the urban context showing a substantial reduction in CO2 emissions. At the same time attention is drawn to an often-overlooked aspect regarding renewable energy technologies, in that despite having low operating costs their overall benefits are often not well understood and consequently are often evaluated as being less profitable than fossil fuel alternatives, even though they are future proof about energy cost.
The aim of the present paper is to describe the role of renewable energy technologies and zero carbon technologies in covering the future increased energy demand for cooling.
The integration of photovoltaics in the urban environment through PV facades, pavements, and shading devices are discussed.
The role of Information and Computer Technology and smart grids in the efficient management of renewables in urban scale is discussed. The role of smart metering, users ‘integration and demand response capabilities for future zero energy urban neighborhoods is revealed.
The fate of phosphorus in groundwater needs to be understood because phosphorus-rich groundwater is discharged into surface water bodies, which causes eutrophication, especially in urbanized areas. ...The present study investigated the spatial distributions and driving forces related to the groundwater phosphate levels in various aquifers in the Pearl River Delta (PRD), which has undergone three decades of urbanization, as well as the relationship between groundwater phosphate and arsenic was also discussed. The results showed that most of the high-phosphate (>1.53 mg/L) groundwater occurred in granular aquifers. The proportion of high-phosphate groundwater in granular aquifers was more than four times that in fissured aquifers, whereas high-phosphate groundwater was not observed in karst aquifers in the PRD. High-phosphate groundwater primarily occurred in urbanized areas in the PRD, and the proportion of high-phosphate groundwater had a significant positive correlation with the urbanization level. In granular aquifers, reductive environment and alkalization led to enrichment of the groundwater with phosphate. Anthropogenic sources such as wastewater from township-village enterprises (TVE) and animal wastes were the main sources of high-phosphate groundwater in urbanized areas, and the external input of phosphate enriched the groundwater arsenic levels in urbanized areas. By contrast, geogenic sources such as the release of phosphate from the reduction of Fe/Mn (hydr)oxides and the seawater intrusion accompanied by the release of phosphate from secondary minerals were mainly responsible for the occurrence of high-phosphate groundwater in peri-urban and non-urbanized areas, respectively. The high concentrations of both phosphate and arsenic in groundwater in fissured aquifers were mainly attributed to the infiltration of wastewater from TVEs. In contrast to the granular aquifers, the groundwater Eh and pH conditions were not conductive to the occurrence of high-phosphate groundwater in fissured aquifers.
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•Mostly high-phosphate groundwater occurs in granular aquifers in the PRD.•High-phosphate groundwater is positive correlation with the urbanization level.•Low Eh values and alkalization enhance groundwater phosphate in granular aquifers.•TVE wastewater and animal wastes are the main sources for high-phosphate groundwater.•External input of phosphate enhance groundwater arsenic enrichment in urbanized areas.
Township–village enterprises wastewater and animal wastes were the main sources of high-phosphate groundwater in study area. Low Eh and high pH enhanced groundwater phosphate in granular aquifers.
•Electrification of building thermal energy demand is more often provided by SGS•Cumulative effects on urban groundwater temperature are observed•A numerical model of SGS exploitation was built and ...calibrated against real data•Model outcomes reveal the presence of mutual negative and positive interferences•Technical suggestions are proposed for a more sustainable management
The use of shallow geothermal systems (SGS) as a proficient technology to provide clean thermal energy has become increasingly widespread throughout the world, especially in urban environments, with a significant increase in systems density. At European level, the current authorization schemes for new SGS rarely consider the current thermal state of the subsurface and the potential presence of neighbouring systems. The paper presents a pilot urban case study, showing high SGS deployment, analysed through a holistic city-scale 3D numerical model simulating mutual interactions between open and closed-loop systems. Results show that the high amount of installed SGS in limited space is progressively creating mutual hydraulic and thermal interferences: negative, with a reduction of SGS efficiency and sustainability or (rarely) positive, when an accidental and unmanaged synergic effect is established due to favourable exploitation patterns and SGS locations. Numerical modeling further highlighted that the restitution through the vadose zone could be a valid method to hydraulically reinstate the aquifer without significantly altering groundwater undisturbed temperature even at shallow groundwater depth. Results show that neglecting an underground holistic vision of the hydro/thermogeological processes in urban areas could result in long-term severe efficiency losses and environmental issues for SGS solutions, also given the increasing use of shallow geothermal energy in the building air conditioning sector.
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Wind flows inside complex urban environments are determined by the mutual effect of large-scale (i.e., wind above the urban boundary layer, UBL) and local-scale forcing (i.e. constraints into the ...urban canopy layer, UCL). Usually, when the wind field above the UBL is known (e.g. by on-site measurements, OsM), high-resolution microscale models (e.g. CFD) are used to predict the wind inside the UCL. However, standard procedures to map the wind field from an undisturbed position to the UCL are not available yet and several technical aspects need to be investigated. A downscaling method, so-called “static downscaling”, of the wind from mesoscale to microscale is innovatively adopted here to evaluate the performance of two CFD microscale models when predicting the flow in a UCL. The methodology is based on OsM transferred into the UCL by means of so-called “transfer coefficients” calculated by 3D steady RANS simulations for two different spatial extents of the explicitly modeled urban texture (Case A and B). It is discussed in detail the way the transfer coefficients work, how they can be used to understand the correlations between wind above and within the UCL as well as to identify the major limitations of the RANS approach. Results are discussed in qualitative terms and quantified using standard metrics. It is also shown that too high flow rates can occur at the entrance of the waterway of the area of interest and in the outer part of the explicitly modeled urban area, which can be mitigated by “buffer zones”.
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•On-site measurements were performed in Livorno city with LiDAR and anemometers.•RANS simulations on more and less spatially extended cases of Livorno city.•Transferred CFD data were compared to measured data inside the UCL at target points.•The extension of the environment surrounding the target area plays a key role.•Deviations are discussed and effects on wind flow quantified by statistical metrics.
Growing evidence suggests that urban environment may influence cognition and behavior in children, but the underlying pollutant and neurobiological mechanisms are unclear. We evaluated the ...association of built environment and urban natural space indicators during pregnancy and childhood with brain white matter microstructure in preadolescents, and examined the potential mediating role of air pollution and road-traffic noise. We used data of the Generation R Study, a population-based birth cohort in Rotterdam, the Netherlands (n = 2725; 2002–2006) for the primary analyses. Replication of the main findings was attempted on an independent neuroimaging dataset from the PELAGIE birth cohort, France (n = 95; 2002–2006). We assessed exposures to 12 built environment and 4 urban natural spaces indicators from conception up to 9 years of age. We computed 2 white matter microstructure outcomes (i.e., average of fractional anisotropy (FA) and mean diffusivity (MD) from 12 white matte tracts) from diffusion tensor imaging data. Greater distance to the nearest major green space during pregnancy was associated with higher whole-brain FA (0.001 (95%CI 0.000; 0.002) per 7 m increase), and higher land use diversity during childhood was associated with lower whole-brain MD (−0.001 (95%CI -0.002; −0.000) per 0.12-point increase), with no evidence of mediation by air pollution nor road-traffic noise. Higher percentage of transport and lower surrounding greenness during pregnancy were associated with lower whole-brain FA, and road-traffic noise mediated 19% and 52% of these associations, respectively. We found estimates in the same direction in the PELAGIE cohort, although confidence intervals were larger and included the null. This study suggests an association between urban environment and white matter microstructure, mainly through road-traffic noise, indicating that greater access to green space nearby might promote white matter development.
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•12 built environment and 4 urban natural spaces indicators assessed•Assessment from conception up to 9 years of age.•White matter microstructure assessed at 9–12 years old.•Associations between urban environment and white matter microstructure.•Road-traffic noise partially mediated the associations.
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