Investigation of CO2 Variation and Mapping Through Wearable Sensing Techniques for Measuring Pedestrians’ Exposure in Urban Areas

Citizens’ wellbeing is mainly threatened by poor air quality and local overheating due to human-activity concentration and land-cover/surface modification in urban areas. Peculiar morphology and metabolism of urban areas lead to the well-known urban-heat-island effect, characterized by higher air temperature in cities than in their surroundings. The environmental mapping of the urban outdoors at the pedestrian height could be a key tool to identify risky areas for humans in terms of both poor-air-quality exposure and thermal comfort. This study proposes urban environment investigation through a wearable miniaturized weather station to get the spatial distribution of key parameters according to the citizens’ perspective. The innovative system monitors and traces the field values of carbon dioxide (CO2) concentration, such as air temperature and wind-speed values, which have been demonstrated to be related to outdoor wellbeing. The presented monitoring campaign focused on a two-way, two-lane road in Rome (Italy) during traffic rush hours on both working days and weekends. Collected data were analyzed with respect to timing and position, and possible correlations among different variables were examined. Results demonstrated the wearable system capability to catch pedestrian-exposure variability in terms of CO2 concentration and local overheating due to urban structure, highlighting potentials in the citizens’ involvement as observation vectors to extensively monitor urban environmental quality.

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The Synergistic Effect of PM2.5 and CO2 Concentrations on Occupant Satisfaction and Work Productivity in a Meeting Room

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18084109 ◽

2021 ◽

Vol 18 (8) ◽

pp. 4109

Author(s):

Jindong Wu ◽

Jiantao Weng ◽

Bing Xia ◽

Yujie Zhao ◽

Qiuji Song

Keyword(s):

Air Quality ◽

Synergistic Effect ◽

Work Productivity ◽

Co2 Concentration ◽

Human Beings ◽

Meeting Room ◽

Negative Effect ◽

Carbon Dioxide Co2 ◽

Occupant Satisfaction ◽

Pm2.5 Concentration

High indoor air quality is crucial for the health of human beings. The purpose of this work is to analyze the synergistic effect of particulate matter 2.5 (PM2.5) and carbon dioxide (CO2) concentration on occupant satisfaction and work productivity. This study carried out a real-scale experiments in a meeting room with exposures of up to one hour. Indoor environment parameters, including air temperature, relative humidity, illuminance, and noise level, were controlled at a reasonable level. Twenty-nine young participants were participated in the experiments. Four mental tasks were conducted to quantitatively evaluate the work productivity of occupants and a questionnaire was used to access participants’ satisfaction. The Spearman correlation analysis and two-way analysis of variance were applied. It was found that the overall performance declined by 1% for every 10 μg/m3 increase in PM2.5 concentration. Moreover, for every 10% increase in dissatisfaction with air quality, productivity performance decreased by 1.1% or more. It should be noted that a high CO2 concentration (800 ppm) has a stronger negative effect on occupant satisfaction towards air quality than PM2.5 concentration in a non-ventilated room. In order to obtain optimal occupant satisfaction and work productivity, low concentrations of PM2.5 (<50 μg/m3) and CO2 (<700 ppm) are recommended.

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PARAMETERS OF INTEREST FOR THE DESIGN OF GREEN INFRASTRUCTURE

Journal of Urban and Environmental Engineering ◽

10.4090/juee.2019.v13n1.092101 ◽

2019 ◽

pp. 92-101

Author(s):

Marija Šperac ◽

Dino Obradović

Keyword(s):

Air Quality ◽

Urban Environment ◽

Air Temperature ◽

Green Infrastructure ◽

Land Surface ◽

Urban Areas ◽

Hydrological Cycle ◽

Urban Environments ◽

Land Surfaces ◽

Selection Of

The urbanization process significantly reduced the permeability of land surfaces, which affected the changes of runoff characteristics and the relations in the hydrological cycle. In urban environments, the relationships within the hydrological cycle have changed in quantity, in particular: precipitation, air temperature, evaporation, and infiltration. By applying the green infrastructure (GI) to urban environments is beneficial for the water resources and the social community. GI has an effect on the improvement of ecological, economic, and social conditions. Using GI into urban areas increases the permeability of land surfaces, whereby decreasing surface runoff, and thus the frequency of urban floods. It also has a significant influence on the regulation of air quality, water purification, climate change impact, and the changes in the appearance of the urban environment. When planning and designing the GI, it is necessary to identify the type of GI and determine the size and location of the selected GI. Since each urban environment has its own characteristics, it is necessary to analyze them before deciding on the GI. The paper analyzed meteorological parameters (precipitation, air temperature, insolation, air humidity) affecting the selection of GI types, using the specific example of an urban environment – the City of Osijek, Croatia. Significant parameters when designing GI are operation and maintenance These parameters directly affect the efficiency of GI. The proper selection of GI and its location results in maximum gains: the reduction of land surface drainage - drainage of the sewage system, purification and retention of precipitation at the place of production, the improvement of air quality, and the improvement of living conditions in urban environments

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Mitigation Strategies for Overheating and High Carbon Dioxide Concentration within Institutional Buildings: A Case Study in Toronto, Canada

Buildings ◽

10.3390/buildings10070124 ◽

2020 ◽

Vol 10 (7) ◽

pp. 124 ◽

Cited By ~ 1

Author(s):

Claire Tam ◽

Yuqing Zhao ◽

Zaiyi Liao ◽

Lian Zhao

Keyword(s):

Carbon Dioxide ◽

Air Quality ◽

Indoor Air Quality ◽

Air Temperature ◽

Indoor Air ◽

Indoor Environment ◽

Thermal Conditions ◽

Co2 Concentration ◽

Hvac System

Indoor air quality and thermal conditions are important considerations when designing indoor spaces to ensure occupant health, satisfaction, and productivity. Carbon dioxide (CO2) concentration and indoor air temperature are two measurable parameters to assess air quality and thermal conditions within a space. Occupants are progressively affected by the indoor environment as the time spent indoors prolongs. Specifically, there is an interest in carrying out investigations on the indoor environment through surveying existing Heating, Ventilation, Air Conditioning (HVAC) system operations in classrooms. Indoor air temperature and CO2 concentration in multiple lecture halls in Toronto, Canada were monitored; observations consistently show high indoor air temperature (overheating) and high CO2 concentration. One classroom is chosen as a representative case study for this paper. The results verify a strong correlation between the number of occupants and the increase in air temperature and CO2 concentration. Building Energy Simulation (BES) is used to investigate the causes of discomfort in the classroom, and to identify methods for regulating the temperature and CO2 concentration. This paper proposes retro-commissioning strategies that could be implemented in institutional buildings; specifically, the increase of outdoor airflow rate and the addition of occupancy-based pre-active HVAC system control. The proposed retrofit cases reduce the measured overheating in the classrooms by 2-3 °C (indoor temperature should be below 23 °C) and maintain CO2 concentration under 900 ppm (the CO2 threshold is 1000 ppm), showing promising improvements to a classroom’s thermal condition and indoor air quality.

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Indoor air quality and health in schools

Jornal Brasileiro de Pneumologia ◽

10.1590/s1806-37132014000300009 ◽

2014 ◽

Vol 40 (3) ◽

pp. 259-268 ◽

Cited By ~ 16

Author(s):

Ana Maria da Conceição Ferreira ◽

Massano Cardoso

Keyword(s):

Air Quality ◽

Indoor Air Quality ◽

Indoor Air ◽

Respiratory Diseases ◽

Reference Value ◽

Signs And Symptoms ◽

Co2 Concentration ◽

Air Pollutant ◽

Carbon Dioxide Co2 ◽

The City

Objective: To determine whether indoor air quality in schools is associated with the prevalence of allergic and respiratory diseases in children. Methods: We evaluated 1,019 students at 51 elementary schools in the city of Coimbra, Portugal. We applied a questionnaire that included questions regarding the demographic, social, and behavioral characteristics of students, as well as the presence of smoking in the family. We also evaluated the indoor air quality in the schools. Results: In the indoor air of the schools evaluated, we identified mean concentrations of carbon dioxide (CO2) above the maximum reference value, especially during the fall and winter. The CO2 concentration was sometimes as high as 1,942 ppm, implying a considerable health risk for the children. The most prevalent symptoms and respiratory diseases identified in the children were sneezing, rales, wheezing, rhinitis, and asthma. Other signs and symptoms, such as poor concentration, cough, headache, and irritation of mucous membranes, were identified. Lack of concentration was associated with CO2 concentrations above the maximum recommended level in indoor air (p = 0.002). There were no other significant associations. Conclusions: Most of the schools evaluated presented with reasonable air quality and thermal comfort. However, the concentrations of various pollutants, especially CO2, suggest the need for corrective interventions, such as reducing air pollutant sources and improving ventilation. There was a statistically significant association between lack of concentration in the children and exposure to high levels of CO2. The overall low level of pollution in the city of Coimbra might explain the lack of other significant associations.

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Investigating the relationship between variation of greenhouse gases concentrations and humidex

E3S Web of Conferences ◽

10.1051/e3sconf/20187411004 ◽

2018 ◽

Vol 74 ◽

pp. 11004 ◽

Cited By ~ 1

Author(s):

Anies Ma’rufatin ◽

Haryoto Kusnoputranto ◽

Kardono

Keyword(s):

Greenhouse Gases ◽

Thermal Comfort ◽

Air Temperature ◽

Urban Areas ◽

Negative Relationship ◽

Co2 Concentration ◽

Comfort Level ◽

Human Thermal Comfort ◽

Ch4 Concentration ◽

The Relationship

The increasing greenhouse gases (GHGs) in the atmosphere contribute to increasing average temperature earth’s surface. This research investigated relationship between variation of GHGs and human thermal comfort based on humidity index (humidex). This study applied humidex, an indices to assess the thermal comfort. The analysis was done by examining the observational data from two different monitoring stations in Serpong and Bogor. The result showed that the average CO2 concentration per month ranged between 422 and 453 ppm in Serpong, whereas in Bogor the average CO2 concentration per month was 413-426 ppm. The average CH4 concentration per month variation in Serpong was 2.05-2.65 ppm. While in Bogor, the average CH4 concentration per month variation ranged between 1.92 and 2.08 ppm. The difference of GHGs concentration in each location might be influenced by meteorological parameters and environmental characteristics. The comfort level according to humidex in Serpong was 30.5-41.5 whereas in Bogor was 29.4-38.5. The correlation between GHGs concentration and air temperature in urban areas in both stations showed a significant and strong but negative relationship. The relationship between GHGs concentration and humidex was indirectly indicated by the relationship of GHGs concentration on air temperature as indicator of humidex.

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Diurnal and Seasonal Variations of Carbon Dioxide (CO2) Concentration in Urban, Suburban, and Rural Areas around Tokyo

Atmosphere ◽

10.3390/atmos9100367 ◽

2018 ◽

Vol 9 (10) ◽

pp. 367 ◽

Cited By ~ 11

Author(s):

Ryoichi Imasu ◽

Yuka Tanabe

Keyword(s):

Carbon Dioxide ◽

Seasonal Variations ◽

Rural Areas ◽

Urban Areas ◽

Local Governments ◽

Inversion Layer ◽

Co2 Concentration ◽

Early Spring ◽

Hourly Data ◽

Carbon Dioxide Co2

Site environments and instrumental characteristics of carbon dioxide (CO2) measurements operated by local governments in the Kanto Plain, the center of which is Tokyo, were summarized for this study. The observation sites were classified into environments of three types: urban, suburban, and woodland. Based on a few decades of accumulated hourly data, the diurnal and seasonal variations of CO2 concentrations were analyzed as a composite of anomalies from annual means recorded for each site. In urban areas, the highest concentrations appear before midnight in winter. The second peak corresponds to the morning rush hour and the strengthening of the inversion layer. Suburban areas can be characterized as having the highest concentration before dawn and the lowest concentration during the daytime in summer in association with the activation of respiration and photosynthesis of vegetation. In these areas, concentration peaks also appear during the morning rush hour. Woodland areas show background features, with the highest concentration in early spring, which are higher than the global background by about 5 ppmv.

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Preliminary Results of Air Pollution Status in Selected Roadsides in Jalingo, Taraba State Nigeria

Indonesian Journal of Environmental Management and Sustainability ◽

10.26554/ijems.2021.5.3.118-123 ◽

2021 ◽

Vol 5 (3) ◽

pp. 118-123

Author(s):

Maxwell Obia Kanu ◽

Terkaa Victor Targema ◽

Gideon Maumee Abednego

Keyword(s):

Air Pollution ◽

Air Quality ◽

Traffic Congestion ◽

Urban Areas ◽

Ambient Air ◽

Acceptable Limit ◽

Pollution Levels ◽

The Mean ◽

Carbon Dioxide Co2 ◽

Mean Concentration

The rapid increase in vehicular activities in the past two centuries contributes vastly to air pollution levels. In as much as Social interactions and economic growth are well enhanced by vehicular transportation in many developing countries, it is unfortunate that exhausts from vehicles contribute immensely to ambient air quality especially in the urban areas. The concentrations of carbon monoxides (CO) and carbon dioxide (CO2) emissions in selected roadsides in Jalingo have been assessed. Four roads were used as sample locations where the concentration of CO2 and CO were measured using an air quality meter for four weeks. The mean concentration of CO2 and CO obtained were respectively as follows: 542.25 ppm and 7.49 ppm for the roadblock, 540.05 ppm and 5.55 ppm for Hammaruwa way, 598.81 ppm and 17.42 ppm for market road, and 463.80 ppm and 1.08 ppm for Nigerian Labour Congress (NLC) road (control). Based on the acceptable limit of CO2 (600 ppm), the Roadblock road, Hammaruwa way, and the NLC/control road are safe. Only the market road had value that exceeded the acceptable limit, and it may be attributed to high vehicular activities on the roadsides. Therefore, more alternative roads should be constructed in other to minimize traffic congestion and also, the use of nose masks should be encouraged. For the CO, all the sites are safe because they fall within the acceptable level of CO (1-70 ppm).

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A new approach for highly resolved air temperature measurements in urban areas

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-4-1001-2011 ◽

2011 ◽

Vol 4 (1) ◽

pp. 1001-1019 ◽

Cited By ~ 3

Author(s):

M. Buttstädt ◽

T. Sachsen ◽

G. Ketzler ◽

H. Merbitz ◽

C. Schneider

Keyword(s):

Air Temperature ◽

Urban Areas ◽

Thermal Conditions ◽

Research Programme ◽

Temperature Data ◽

Urban Structure ◽

New Approach ◽

Local Climate ◽

Climate Conditions ◽

The City

Abstract. In different fields of applied local climate investigation, highly resolved data of air temperature are of great importance. As a part of the research programme entitled City2020+, which deals with future climate conditions in agglomerations, this study focuses on increasing the quantity of urban air temperature data intended for the analysis of their spatial distribution. A new measurement approach using local transport buses as "riding thermometers" is presented. By this means, temperature data with a very high temporal and spatial resolution could be collected during scheduled bus rides. The data obtained provide the basis for the identification of thermally affected areas and for the investigation of factors in urban structure which influence the thermal conditions. Initial results from the ongoing study, which show the temperature distribution along different traverses through the city of Aachen, are presented.

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A Regional Geography Approach to Understanding the Environmental Changes as a Consequence of the COVID-19 Lockdown in Highly Populated Spanish Cities

Applied Sciences ◽

10.3390/app11072912 ◽

2021 ◽

Vol 11 (7) ◽

pp. 2912

Author(s):

Jesús Rodrigo-Comino ◽

José María Senciales-González

Keyword(s):

Air Quality ◽

Air Temperature ◽

Urban Areas ◽

Environmental Changes ◽

Urban Climate ◽

Global Scale ◽

Point Of View ◽

Atmospheric Conditions ◽

Economic Activities ◽

Economic Point

Spain has been highly impacted by the COVID-19 pandemic, which is reflected at different scales. From an economic point of view, lockdowns and the reduction of activities have damaged the country (e.g., complete lockdown from March 13 to June 21, 2020). However, it is not clear if the associated environmental impacts could be observed in 2020. Currently, studies on the effects of the lockdown (e.g., decrease in economic activities, transport and social communication) on specific parameters related to climate change, such as air temperature or air pollution, due to a drastic decrease in human activities are rare. They are focused on specific cities and short periods of time. Therefore, the main goal of our research will be to assess the records of air temperature and air quality during the whole of 2020 compared to references from previous years (30 years for air temperature and 10 for air quality). We paid attention to the possible effects of the reduction of activities (e.g., tourism and transport) in March, April and May and the different restrictions of each lockdown in Spain. To achieve this goal, five urban climate stations with long-term time series within the most populated cities of Spain were analyzed (Barcelona, Madrid, Málaga, Sevilla and Valencia). We conclude that it is possible to affirm that the impacts of the COVID-19 pandemic on the atmospheric conditions in 2020 are not clear and not strictly focused on the lockdown or reduction of activities in these urban areas. No evidence of a reduction in the annual air temperature was found, and only a minimum reduction of rates of pollutants was registered in the highly populated cities of Spain. Therefore, it is worth confirming that these changes could be affected by other factors, but on a global scale and not directly due to the COVID-19 pandemic. Considering recent studies on the relationships between air pollutants, temperature and the spreadability of COVID-19, green policies must be further imposed in urban cities, since temperatures do not stop increasing year by year.

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Solar radiation exposure of shielded air temperature sensors and measurement error evaluation in an urban environment: a preliminary study in Florence, Italy

Advances in Science and Research ◽

10.5194/asr-3-9-2009 ◽

2009 ◽

Vol 3 (1) ◽

pp. 9-12 ◽

Cited By ~ 2

Author(s):

M. Petralli ◽

L. Massetti ◽

S. Orlandini

Keyword(s):

Solar Radiation ◽

Radiation Exposure ◽

Air Temperature ◽

Urban Areas ◽

Thermal Conditions ◽

Surface Characteristics ◽

Temperature Sensors ◽

Island Effect ◽

Synoptic Conditions ◽

Solar Radiation Exposure

Abstract. Particularly in summer, thermal conditions in urban areas are influenced by solar radiation and human health can be strongly affected by the higher temperature regime increased by the Urban Heat Island effect (UHI). Many studies have been carried out to estimate the temperature distribution in urban areas and some of these use or are based on data collected by meteorological instruments placed within the cities. At microscale, temperature collected by sensors can be influenced by the underlying surface characteristics and the closeness to warm surfaces. The aim of this study is to investigate how different exposure to solar radiation can affect air temperature measurement in streets and gardens. The study was carried out on two different areas in Florence during summer 2007. Shielded air temperature sensors were placed in a street of a high density built-up area and in a green area. Each area was monitored by two sensors, sited in different solar radiation exposure: one in a sunny area and the other in a shaded one. A preliminary data analysis showed a difference in every site between the air temperature values collected by the two sensors especially from the morning to the afternoon. The relationship between air temperature differences and synoptic meteorological conditions were also analyzed. In conclusion, the solar radiation exposure of a monitoring station is an important parameter that must be considered both during the instruments siting and the analysis of data collected by sensors previously placed. The result of this study shows that during particular synoptic conditions, data collected by the two sensors of the same area can be different.

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