Search Results (21)

High ozone (O₃) concentrations are frequently recorded in São Paulo Megacity, with extreme O₃ levels often linked to high temperatures and heatwaves, phenomena expected to intensify with climate change. The co-occurrence of extreme O₃ and heatwaves poses amplified risks to environmental and human health. Hence, this study aims to analyze individual and compound extreme O₃ and heatwave events and assess the associated atmospheric patterns. Hourly O₃ and temperature (T) data from 20 sites (1998–2023) were used to calculate the maximum daily 8 h average O₃ (MD8A-O₃) and maximum daily temperature (Tmax). The Mann–Kendall test identified trends for these variables. The 90th percentile of data from September to March defined thresholds for extreme events. Events were classified as extreme when MD8A-O₃ and Tmax exceeded their thresholds for at least six consecutive days. ERA5 data were used to evaluate atmospheric patterns during these events. The results show positive trends in MD8A-O₃ in 62% of sites, with values exceeding WHO Air Quality Guidelines, alongside positive Tmax trends in 90% of sites. Over the study period, four compound events, seven heatwaves, and four extreme O₃ events were identified. Compound and individual events were associated with the South America Subtropical Anticyclone and positive temperature anomalies. Individual O₃ events were linked to cold anomalies south of 30° S and positive geopotential height anomalies at 850 hPa. These findings highlight the increasing occurrence of extreme O₃ and heatwaves in São Paulo and their atmospheric drivers, offering insights to enhance awareness, forecasting, and policy responses to mitigate health and environmental impacts. Full article

This study evaluates nine Planetary Boundary Layer (PBL) turbulence parameterization schemes from the Weather Research and Forecasting (WRF) mesoscale meteorological model, comparing hourly values of meteorological variables observed and simulated at the surface of the Metropolitan Region of São Paulo (MRSP). The numerical results were objectively compared with high-quality observations carried out on three micrometeorological platforms representing typical urban, suburban, and rural land use areas of the MRSP, during the 2013 summer and winter field campaigns as part of the MCITY BRAZIL project. The main objective is to identify which PBL scheme best represents the diurnal evolution of conventional meteorological variables (temperature, relative and specific humidity, wind speed, and direction) and unconventional (sensible and latent heat fluxes, net radiation, and incoming downward solar radiation) on the surface. During the summer field campaign and over the suburban area of the MRSP, most PBL scheme simulations exhibited a cold and dry bias and overestimated wind speed. They also overestimated sensible heat flux, with high agreement index and correlation values. In general, the PBL scheme simulations performed well for latent heat flux, displaying low mean bias error and root square mean error values. Both incoming downward solar radiation and net radiation were also accurately simulated by most of them. The comparison of the nine PBL schemes indicated the local Mellor-Yamada-Janjic (MYJ) scheme performed best during the summer period, particularly for conventional meteorological variables for the land use suburban in the MRSP. During the winter field campaign, simulation outcomes varied significantly based on the site’s land use and the meteorological variable analyzed. The MYJ, Bougeault-Lacarrère (BouLac), and Mellor-Yamada Nakanishi-Niino (MYNN) schemes effectively simulated temperature and humidity, especially in the urban land use area. The MYNN scheme also simulated net radiation accurately. There was a tendency to overestimate sensible and latent heat fluxes, except for the rural land use area where they were consistently underestimated. However, the rural area exhibited superior correlations compared to the urban area. Overall, the MYJ scheme was deemed the most suitable for representing the convectional and nonconventional meteorological variables on the surface in all urban, suburban, and rural land use areas of the MRSP. Full article

Megacities across the planet face a range of economic and territorial challenges. Future climate predictions suggest that several urban areas will present greater social and environmental problems in the coming decades, which makes strategic planning urgent and necessary for sustainable adaptation in all senses, i.e., economic, social and environmental. Some cities in the global south, such as Sao Paulo, had a history of rapid urban development without environmental planning throughout the 20th century, making urgent the need to expand green infrastructure, especially with the connection of forest fragments to the urban fabric. Therefore, this study aimed (i) to evaluate the increase in official urban parks throughout history, considering the spatialization and typologies of new parks in the territory of Sao Paulo, (ii) to understand the ecosystem services provided by urban forests and its distribution in the city, and (iii) to associate the temporal stability attributes of recent environmental secretaries with the officialization of protected areas in the city of Sao Paulo. The results revealed that only at the beginning of the 21st century was there an effective increase in the number of protected areas that shelter fragments of urban forests, contrasting the strong socio-spatial segregation that occurred in the 20th century with an economically vulnerable population that occupied peripheral areas with greater natural disaster risk. Political stability was a key factor for success in the environmental management of a megacity. The scenarios of environmental injustice reported in this manuscript can be revised with the implementation of policies and actions aimed at expanding green infrastructure in strategic sites, based on specific park typologies for each location. Such actions may come from public–private partnerships (PPP) that subsidize the socio-environmental transformation of the territory. Full article

This article aims to explore the relationship between social innovation and opportunities for innovation in public services, focusing on a range of initiatives intended to improve services and infrastructure for pedestrians in the city of São Paulo, the largest Brazilian megacity, namely: Reduced Speed Zone, Safe Routes to School, and Complete Street. We apply the multiagent framework for innovation in services, incorporating nine variables that characterize social innovation. As for the main results, in the local context, there is the role of third-sector organizations in creating and introducing solutions for active mobility services through co-creation. Co-creation was identified as a key process and is highlighted in actions to obtain community involvement, interviews to measure the acceptance of the project and detect potential points of improvement not foreseen in the pilot project, participatory workshops, installation of informative and interactive panels, preparation and approval of the temporary intervention project, and joint discussion and analysis with municipal agencies about the points that could receive the temporary intervention. The initiatives are recent and cover specific geographic–temporal boundaries. There is a need to deepen the dialogue between social innovation and service innovation with the co-design and co-construction approaches proposed in this paper, applied in different political, economic, urban, and social contexts. In addition, some barriers are highlighted relating to the lack of public funding, compliance with national regulations, political will, non-partisan actions, and long-term vision. There are potentials for the continuous introduction of innovations for the improvement of public services for pedestrians, promoting participatory restructuring as a form of (re)appropriation of urban public spaces. Full article

We aimed to study the daily formaldehyde (HCHO) columns over urban and forested areas in São Paulo State, Brazil, from rhe TROPOMI spectrometer onboard the Sentinel-5P satellite during 2020. Nineteen specific areas were defined in four regions: 3 areas in each of two preserved Atlantic Forests (PEMD and PETAR), 3 in a sugarcane growing region (NERG) and 10 in the Metropolitan Area of São Paulo (MASP), among which 2 areas are in the Morro Grande reserve, which is a significant remnant of Atlantic Forest outside the densely urbanized area of MASP. An analysis of variance and Tukey’s test showed that the mean annual columns over the Morro Grande reserve ($1.69\pm 1.05\times 10$⁻⁴ mol/m² and $1.73\pm 1.07\times 10$⁻⁴ mol/m²) presented greater statistical similarity with the forest and rural areas of the state (<$1.70\times 10$⁻⁴ mol/m²) than with MASP (>$2.00\times 10$⁻⁴ mol/m²), indicating few effects from megacity anthropogenic emissions. Case studies addressing selected days in 2020 showed that fires in and around the state were related to episodes of maximum density of HCHO columns. The results showed significant seasonality, with lower concentrations during summer (wet season) and higher concentrations during winter and spring (dry and transition dry–wet seasons). Full article

A recent drought in Southeast Brazil affected the Cantareira reservoirs system (CRS), which supplies water to São Paulo megacity, and raised concerns on the impacts that climate change may have on the water budget at the watershed scale. We propose to identify the particular and summed contributions of key climatic variables on the variability of the water budget in Jaguari basin, the main CRS tributary, using forcing–response relationships derived from climate projections and individual elasticities of variables to temperature. Besides, we investigated whether hydrological effects of the anomalous drought were comparable to patterns simulated in the future climate. A thoroughly calibrated hydrological model for evapotranspiration (ET) and discharge (Q) was used to address our questions. We found opposite impacts in the future mostly driven by rainfall changes: under increasing (decreasing) rainfall, the mean ET increased (decreased) up to +25% (−10%) and Q increased (decreased) by +90% (−50%). Higher carbon dioxide concentrations strongly depleted the stomatal conductance, and thus the mean ET, which in turn increased the mean Q in near proportions. Major critical impacts for water management are suggested by the results. Even with a small reduction of precipitation, the discharge patterns in the drought event were replicated at similar intensities. Full article

This work presents the use of two elastic lidar systems to assess the horizontal variation of the PBL height (PBLH) and aerosol layer aloft in the São Paulo Megacity. These two lidars performed simultaneous measurements 10.7 km apart in a highly urbanized and relatively flat area of São Paulo for two winter months of 2019. The results showed that the PBLH differences display diurnal variation that depends on the PBL during daytime growth phases. Cloud and sea breeze effects control most of PBLH variation. In the absence of cloud and sea breeze, the maximum difference (~300 m) occurs in the rapid development stage and is due to topographic effects. When the PBL approaches its maximum daily value, it tends to level off with respect to the topography. In addition, it was presented a method that combines elastic lidar (to detect an aerosol layer) and satellite data (to classify such a layer from Aerosol Optical Depth (AOD) and Aerosol Index (AI) information) for the detection of biomass burning events. This methodology demonstrated that the variations caused by Biomass Burning in AOD and AI enable both the detection of aerosol plumes originating from biomass burning and the identification of their origin. Full article

We studied the health effects of economic development in heavily urbanized areas, where congestion poses a challenge to environmental conditions. We employed detailed data from air pollution and birth records around the metropolitan area of São Paulo, Brazil, between 2002 and 2009. During this period, the megacity experienced sustained growth marked by the increases in employment rates and ownership of durable goods, including automobiles. While better economic conditions are expected to improve infant health, air pollution that accompanies it is expected to do the opposite. To untangle these two effects, we focused on episodes of thermal inversion—meteorological phenomena that exogenously lock pollutants closer to the ground—to estimate the causal effects of in utero exposure to air pollution. Auxiliary results confirmed a positive relationship between thermal inversions and several air pollutants, and we ultimately found that exposure to inversion episodes during the last three months of pregnancy led to sizable reductions in birth weight and increases in the incidence of preterm births. Increased pollution exposure induced by inversions also has a significant impact over fetal survival as measured by the size of live-birth cohorts. Full article

Since the 1990s, many countries have witnessed the emergence of organizations publishing environmental, social, and quality-of-life indicators at a city level in order to promote public awareness, democratic participation, and sustainability policies. Many such initiatives are short-lived, however, and reasons for their success and failure under-researched. Using interviews, surveys, and documental data, we explored the survival rates, obstacles, and achievements of 49 initiatives in 10 Latin American countries. Contrary to those in other world regions, most initiatives have civil society stakeholders (notably universities, media, and businesses), excluding governments. Implementing citizen perception surveys proved effective to gain public attention. Several initiatives obtained name recognition and policy influence, which are significant achievements in megacities such as Bogotá, São Paulo, and Lima, where numerous NGOs vie for attention. Frequent obstacles include a lack of finances. After a seven-year period (2014–2021), 55% of the sampled initiatives remained active, ranging from 90% in Colombia to none in other countries. Organizational continuity appeared to be associated with network membership and discontinuity with diverging obstacles, including political pressures in some countries (e.g., Mexico), data scarcity in poorer ones (e.g., Bolivia), and a lack of sustained interest in relatively richer ones (e.g., Chile). Recent increases in socio-economic inequalities are strengthening the potential of community indicators. Full article

Urbanization and climate change are two major issues that humanity faces in the 21st century. Megacities are large urban agglomerations with more than 10 million inhabitants that emerged in the 20th century. The world’s top 100 economies include many North and South American megacities, such as New York, Los Angeles, Mexico City, Sao Paulo and Buenos Aires; European cities such as London and Paris; and Asian cities such as Tokyo, Osaka, Seoul, Beijing and Mumbai. This paper addresses a dearth of megacity energy metabolism models in the literature. Cross-sectional data for 36 global megacities were collected from many literature and Internet sources. Variables included megacity name, country and region; population; area; population density; (per capita) GDP; income inequality measures; (per capita) energy consumption; household electricity prices; (per capita) carbon and ecological footprint; degree days; average urban heat island intensity; and temperature and precipitation. A descriptive comparison of the characteristics of megacities was followed by ordinary least squares with heteroskedasticity-robust standard errors that were used to estimate four alternative multiple regression models. The per-capita carbon footprint of megacities was positively associated with the megacity GDP per capita, and the megacity ecological footprint; and negatively associated with country income inequality, a low-income country dummy, the country household electricity price, and the megacity annual precipitation. Targeted policies are needed, but more policy autonomy should be left to megacities. Collecting longitudinal data for megacities is very challenging but should be a next step to overcome misspecification and bias issues that plague cross-sectional approaches. Full article

Currently, it is important to develop strategic frameworks to support the selection of sustainable resource recovery solutions. This study applies a new framework for planning, implementation, and assessment of resource recovery strategies for a full-scale wastewater treatment plant (WWTP) in São Paulo megacity. The framework comprises several steps based on case study-specific data and information from current literature. Data were collected from various sources: a survey with a wastewater treatment utility, national and regional databases, and review of local regulations and international literature. Treatment configuration, wastewater and by-products composition, potential demand (for water, energy, and phosphorus), stakeholder identification, and local legislation were thoroughly discussed regarding decision-making on resource recovery. Scenario analysis was used to explore suitable nutrient and energy recovery measures based on indicators. Biogas recovery and sewage sludge composting showed more favorable conditions due to similar experiences in the area and robust legislation. The proposed framework is a simplified tool, and its application can support managers to get information on resource recovery and how to plan such initiatives in easier ways to facilitate wiser decision-making, and better operation and management. The results on framework use and refinement can guide potential applications in other contexts and stimulate public policy formulation and further research. Full article

This study investigated people’s attitudes towards noise inside their homes. Online questionnaire surveys were conducted in Seoul, London, and São Paulo. The questionnaire was designed to assess annoyance caused by noise from neighbours and environmental noise (transportation). Information was also collected on situational, personal, and socio-demographic variables. Respondents that were more annoyed by outdoor noise inside their dwelling reported higher neighbour noise annoyance. In Seoul, neighbour noise was found to be more annoying than outdoor noise, and those with higher noise sensitivity reported higher annoyance towards neighbour noise. However, neighbour noise and outdoor noise was found to be equally annoying in London and São Paulo. For neighbour noise, the average percentage of respondents hearing structure-borne sources compared to airborne sources differed in each city. Most neighbour noise sources in São Paulo gave rise to higher annoyance ratings than Seoul and London. Education and income levels had a limited effect on annoyance and coping strategy. Annoyance with indoor noise from neighbours was found to have stronger relationships with cognitive and behavioural coping strategies than outdoor noise annoyance. Full article

The study described in this manuscript analyzed the effects of quarantine and social distancing policies implemented due to the Coronavirus Disease 2019 (COVID-19) pandemic on air pollution levels in four western megacities: São Paulo in Brazil; Paris in France; and Los Angeles and New York in the United States. The study investigated the levels of four air pollutants—Carbon monoxide (CO), Ozone (O₃), Fine Particulate (PM_2.5) and Nitrogen dioxide (NO₂)—during the month of March 2020, compared to 2015–2019, in the urban air of these metropolitan areas, controlling for meteorological variables. Results indicated reductions in the levels of PM_2.5, CO and NO₂, with reductions of the latter two showing statistical significance. In contrast, tropospheric ozone levels increased, except in Los Angeles. The beneficial health effects of cleaner air might also help prevent deaths caused by the epidemic of COVID-19 in megacities by diminishing pressure on hospitals and health equipment. Future actions for the re-starting of non-essential economic activities in these cities should take into consideration the overall importance of health for the individual, as well as for societies. Full article

Proximity to green spaces has been shown to be beneficial to several cardiovascular outcomes in urban spaces. Few studies, however, have analyzed the relationship between these outcomes and green space or land cover uses in low–medium income megacities, where the consequences of rapid and inordinate urbanization impose several health hazards. This study used a subgroup of the dataset from The Brazilian Longitudinal Study of Adult Health ELSA-BRASIL (n = 3418) to identify the correlation between the medical diagnosis of hypertension and green spaces in the megacity of São Paulo. Land cover classification was performed based on the random forest algorithm using geometrically corrected aerial photography (orthophoto). Three different indicators of exposure to green spaces were used: number of street trees, land cover and number of parks within 1 km. We used logistic regression models to obtain the association of the metrics exposure and health outcomes. The number of street trees in the regional governments (OR = 0.937 and number of parks within 1 km (OR = 0.876) were inversely associated with a diagnosis of hypertension. Sixty-three percent of the population had no parks within 1 km of their residence. Our data indicate the need to encourage large-scale street tree planting and increase the number of qualified parks in megacities. Full article

The recognition of metropolitan regions and their growth as a necessary scale of analysis for their integrated management has become a central characteristic of urban planning. The current metropolitan landscape warrants the use of instruments beyond the municipal scale, especially since the economic integration of cities and their development are accentuating urban problems that affect the sustainability of cities. The São Paulo Metropolitan Region (MRSP), one of the world’s megacities, is used as a case study to identify how typologies can contribute to integrated sustainable urban planning and management at the metropolitan level. It applies the territorial analytical typology based on the Driving-Force-Pressure-Situation-Exposure-Effect-Actions (DPSEEA) Environmental Health Matrix to identify the heterogeneity of conditions encountered in large metropolitan regions such as the MRSP. The results show a great variety of environmental and social conditions present in the municipalities of the MRSP that condition the sustainability and health of the urban environment. This typology constitutes a first step to characterize metropolitan regions in socioenvironmental terms using as a conceptual basis a matrix of environmental health indicators, being a precursor in the largest metropolitan region of Brazil. Full article