Marianne Hatzopoulou - Department of Civil & Mineral Engineering

Associate Professor

Canada Research Chair in Transportation and Air Quality
Head of the Transportation and Air Quality research group TRAQ

Visit the Facebook page of the Transportation and Air Quality Research Group

The research of the TRAQ research group was recently featured in the documentary Something in the Air, The Nature of Things: https://www.cbc.ca/natureofthings/episodes/something-in-the-air

Marianne Hatzopoulou
Department of Civil & Mineral Engineering
University of Toronto
35 St. George St.
Toronto, Ontario
Canada, M5S 1A4

Tel.: 416-978-0864
marianne.hatzopoulou@utoronto.ca

Background

My research area bridges between transportation and environmental analysis; and my main expertise is in modelling of road transport emissions and urban air quality as well as evaluating population exposure to air pollution. I am interested in capturing the interactions between the daily activities and travel patterns of urban dwellers and the generation and dispersion of traffic emissions in urban environments. I lead an active research group focusing on modelling traffic emissions and near-road air quality as well as near-road air pollution monitoring and characterization.

Education

BSc (Physics, American University of Beirut, 1999)
MSc (Envtal Technology, Civil Eng., American University of Beirut, 2001)
PhD (Transportation Engineering, Civil Eng., University of Toronto, 2008)
Postdoctoral training (University of Toronto, 2009)
Postdoctoral training (Massachusetts Institute of Technology, 2010)

Research Interests

Traffic-Related Air Pollution

Urban Air Quality

Transportation Engineering

Transportation Planning

Group

An Wang , PhD Candidate

My current research mainly focuses on regional emission inventory estimation and developing modeling chain that bridges traffic assignment, emission calculation, dispersion modeling, exposure and health risk analysis. I am also interested in the energy and environmental impacts of various low-carbon policies and technological trends, especially electrification of transportation system.

Ran Tu, PhD Candidate

Recipient of the 2016-2017: Dr. Mazen Hassounah Graduate Scholarship and the 2017-2018: Dr. M. Hassounah Graduate Scholarship

My PhD research is focused on the improvement of current emission models, and urban traffic policies for emission reduction. I am also interested in air quality related traffic control with emerging technologies, such as autonomous vehicles, and shared mobility.

Laura Minet, PhD Candidate

Recipient of the 2017-2018: Dr. Mazen Hassounah Graduate Scholarship

My research focuses on characterizing ambient air quality to determine population exposure to air pollution. I conduct measurements to understand the relationship between air pollutant levels and the built environment. I also develop dispersion models based on traffic-related air pollutants emissions to develop exposure surfaces and identify hot spots of air pollution.

Junshi Xu, PhD Candidate

Recipient of the Mitacs Globalink Graduate Fellowship (2016-2019)

My research mainly focuses on the development of vehicle emission factors through on-board emission measurements and the generation of real-world drive cycles. My research also involves traffic simulation, emission modelling, and air quality modelling. Besides, I have conducted field measurements to investigate the effects of meteorology, built environment, and traffic on near-road air quality.

arman.ganji@utoronto.ca

Arman Ganji, Research Associate

Monisha Alam, PhD Candidate

Recipient of NSERC PGS D3 (September, 2018 to August, 2021)

Yijun Gai, MASc Candidate

Recipient of the 2017 Jack and Evelyn Tomlinson Scholarship

Marc Saleh, MASc Candidate

My current research focuses on modelling the potential impact of environmental policies at the regional level. These policies vary from investigating the traffic emissions of freight demand management strategies; to understanding the potential impact of vehicle autonomy on vehicle ownership and their respective emissions.

Past Post-Doctoral Fellows

Past graduate students

PhD	Thesis Title	Completion
Shekarrizfard, M.	Investigating population exposure to traffic-related nitrogen oxides through the development and validation of air pollution surfaces	May 2016
Alam, A.	Capturing the effects of urban drive cycles and passenger ridership on transit bus emissions and investigating the potential of emission reduction strategies	August 2015
MSc-Thesis	Thesis Title	Completion
Stogios, C.	Modelling the impact of automated vehicles on traffic emissions	April 2018
Wang, A.	Characterizing near-road air pollution using local-scale emission and dispersion models and validation against in-situ measurements	May 2016
Minet, L.	Testing the robustness of land-use regression models for atmospheric nitrogen dioxide and ozone using data from fixed and mobile monitoring campaigns	May 2016
Lee, A.	Influential parameters of near-roadway ultrafine particles along open patio spaces	Dec. 2015
Deville-Cavellin, L.	Investigating the use of portable air pollution sensors to capture the spatial variability of traffic related air pollution	Aug. 2015
Xu, J.	Investigating the effects of meteorology, built environment and traffic on near road air pollution	Aug. 2015
Sazavar, A.	A peer-to-peer matching system for grocery home delivery	Sept. 2014
Farrel, W.	Understanding the effects of the urban environment on cyclist exposure to near-roadway air pollution	Sept. 2014
Sider, T.	Development of an integrated transport and emissions model and applications for population exposure and environmental justice	Dec. 2013
Ghafghazi, G.	Investigating the effects of traffic calming on near-road air quality using traffic, emissions, and air dispersion modelling	Sept. 2013
MEng-Project	Thesis Title (or general topic)	Completion
Abiola, S.	Impacts of freight traffic on regional air quality	April 2019
Channa-Reddy, B.	Traffic and emission simulation for the King Street pilot project	December 2018
Dean, K.	Modelling ground level PM2.5 concentrations from traffic emissions in downtown Toronto	December 2017
Farhad, M.	Dispersion modelling for highway 25 in Montreal	August 2017
Stokes, J.	Development of land-use regression models based on mobile air pollution data collected along bicycle facilities	August 2016
Addo, A.	Investigation of ultrafine particle number concentrations along busy urban corridors: A comparison of mid-segment and intersection levels	June 2016
Alrijleh, K.	Intra-zonal variability in air pollution across the Plateau neighborhood	May 2016
Khan, M.	Improving Travel Time of Articulated Buses on a Busy Corridor in Montreal, Quebec	May 2016

Past undergraduate trainees

Undergraduate Fellow	Research Project	Duration
Sok, P.	Capturing the effect of land-use and the built environment on traffic-related air quality in large metropolitan areas	Summer 2017
Moreaux, J.	Capturing the effect of land-use and the built environment on traffic-related air quality in large metropolitan areas	Summer 2017
Liu, R.	Processing of individual mobility data and air pollution exposure	Summer 2017
Tu, X.	Data collection and mapping of near-road air quality in Toronto	Summer 2016
Wint, M.S	Data collection and mapping of near-road air quality in Toronto	Summer 2016
Scott, J.	Data collection and mapping of near-road air quality in Toronto	Summer 2016
Kuruparan, S	Data collection and mapping of near-road air quality in Toronto	Summer 2016
Chow, T.	Data collection and mapping of near-road air quality in Toronto	Summer 2016
Kang, T.	Data collection and mapping of near-road air quality in Toronto	Summer 2016
Mario, J.	Data collection and mapping of near-road air quality in Toronto	Summer 2016
Li, J.	Data collection and mapping of near-road air quality in Toronto	Summer 2016
Sun, S.	Panel study of air pollution exposure and cardiovascular health	Summer 2016
Turchet, M.	Microsimulation of traffic emissions on College Street	Summer 2016
Bridi, P.	Mobile sensing of near-road air pollution	Summer 2015
Lueders, B.	Mobile sensing of near-road air pollution	Summer 2015
Nahed, K.	Mobile sensing of near-road air pollution	Summer 2015
Jaber, A.	GPS data collection on-board transit buses	Winter 2015
Wai, J.	Air pollution monitoring in Montreal	Summer 2014
Tack, R.	Testing the performance of air pollution micro-sensors	Winter 2014 Summer 2014 Fall 2014 Summer 2015
Crohmal, G.	Air pollution monitoring in Montreal	Summer 2014
Addo, A.	Analysis of bus transit emissions in Montreal	Winter 2014
Diamond, K.	Air pollution and cardiovascular effects among women cyclists	Summer 2013
Ozols-Mongeau, B.	Air pollution and cardiovascular effects among women cyclists	Summer 2013
Mathewson, E.	Air pollution and cardiovascular effects among women cyclists	Summer 2013
Olcusenler, M.	Air pollution monitoring in urban microenvironments	Summer 2013
Asthana, S.	Quantifying transit bus emissions in Montreal	Summer 2013
Reda, W.	Quantifying transit buses emissions in Montreal	Summer 2013 Fall 2013
Hanson, S.	UFP sampling campaign in Montreal region	Winter 2013
Goulet-Langlois, G.	Modelling start and soak emissions of passenger vehicles	Winter 2013
Moulins, B.	Measuring cyclists’ exposure to air pollution	Summer 2012
Brownlie, M.	Measuring cyclists’ exposure to air pollution	Summer 2012
Neves-Pelchat, J	Measuring cyclists’ exposure to air pollution	Summer 2012 Summer 2013
Luck, R.	Measuring cyclists’ exposure to air pollution	Summer 2012
Truong, T.	Measuring cyclists’ exposure to air pollution	Summer 2012
Pickett, G.	Measuring cyclists’ exposure to air pollution	Summer 2011- Winter 2013
Zukari, M.	Developing a travel emissions footprint on a household basis	Fall 2011 Fall 2012 Winter 2013
Goldstein, N.	Modelling the interaction between vehicle ownership and land-use	Summer 2011 Fall 2011 Winter 2012
Dugum, H	Modelling the interaction between vehicle ownership and land-use	Summer 2011 Fall 201 Winter 2012
Somos, A.	Measuring cyclists’ exposure to air pollution	Summer 2011
Mathez, A.	Calculating the Carbon Footprint of Commuting to McGill	Summer 2011
Chakour, V.	McGill Transport Survey	Summer 2011
Khattab, M.	Modelling the Dispersion of Road Emissions in Lisbon	Summer 2010
Lau, J.	An Integrated Evaluation of Transit Bus Emissions in Toronto	Fall 2008 Winter 2009
NSERC USRA	Research Project	Duration
Gusz, C.	Monitoring of ambient fine particles in Toronto	Summer 2018
Liu, R.	Processing of individual mobility data and air pollution exposure	Summer 2017
Dale, J.	Panel study relating air pollution exposure to cardiovascular outcomes in pedestrians and cyclists	Summer 2016

Research in Images

Distribution of ambient NO2 across the Montreal Island

Distribution of Black Carbon levels across Toronto

Distribution of ultrafine particles in Toronto

Black Carbon across cycling routes in Toronto

Ultrafine particles along cycling routes in Toronto

Testing Aeroqual S500 sensors againts fixed station (RSQA) in Montreal

Thesis Abstracts for TRAQ Graduates (MASc and PhD)

Investigating the Effects of Automated Vehicle Driving Operations on Road Emissions and Traffic Performance-- Chris Stogios, 2018

Automated vehicles (AV) will inevitably have an impact on the movement of people and goods. Assessing the effects of AVs on land use, congestion and the environment have become of great interest to researchers. This study explores the effects of AVs and vehicle electrification on greenhouse gas emissions using traffic microsimulation and emissions modeling. The driving behaviour parameters of a traffic simulation package, most relevant to AVs, are tested within the ranges deemed to be representative of potential AV operations. The effects of AVs are evaluated under both uninterrupted and interrupted traffic flow operating environments, as well as under high and low traffic demand. The main findings indicate that automated vehicles can bring positive changes in terms of emission and traffic flow performance. The significance of the impacts is more evident when AVs are tuned to more aggressive driving settings and especially under high traffic conditions in uninterrupted flow operations.

Investigating Population Exposure to Traffic-Related Nitrogen Oxides through the Development and Validation of Air Pollution Surfaces-- Maryam Shekarrizfard, PhD, 2016

Transport plays a crucial role in urban development by providing access to education, markets, employment, recreation, health care and other key services. Currently, 82% of Canadian commuters drive to work while the remainder rely on public transit and active transportation. In Canada, on-road traffic accounts for 19% of nitrogen oxide (NOx) emissions and in Montreal, Canada’s second largest city, transportation accounts for 85% of NOx emissions. In urban areas, NOx often refers to nitric oxide (NO) and nitrogen dioxide (NO2) since the contribution of other nitrogen oxides is minimal. NOx concentrations are often used as a marker of road traffic emissions and NOx is always higher in the vicinity of roadways and lower further away. Exposure to traffic-related air pollution has been associated with various acute and chronic respiratory and cardiovascular effects and a number of studies have established positive associations between various cancers and exposure to NO2. Most of these assessments have relied on NO2 sampling rather than modelling. Certainly, measurements alone cannot be sufficient for exposure analysis in an urban environment. As a result, there is a need for analysis tools and models that can assist policy-makers in evaluating the impacts of transport policies on urban air quality and population exposure.

This research starts with developing and validating an integrated transportation emission dispersion modelling system to be ultimately used as a tool for evaluating the potential air quality impacts of on-road transportation in the Montreal metropolitan area. We observed that simulated concentrations were reasonably correlated with the observed data when detailed meteorological and dispersion characteristics are accounted for.
The second part of this research explores the possibility of using the transportation emission model, a component of the integrated modelling system, as a proxy to a land-use regression (LUR) model for deriving exposure. We noted similarities in the risks of breast and prostate cancer associated with NO2 derived from the LUR model and NOx derived from the emission model. In the third part of the research, since travel activity, land-use patterns, and the distribution of traffic often lead to inequities in the exposure to vehicle-related air pollutants, we investigated the inequity in the emissions of -and exposure to- traffic-related air pollution, based on LUR NO2 maps and mobility information. For this purpose, long term LUR NO2 maps are used to find the daily average NO2 concentration at the home location (static), and then compared to NO2 maps (dynamic) obtained from the integrated model. We also estimated exposures during travel to identify the contribution of travelling/commuting to daily exposure. The aim of this study is to understand how individuals’ mode choices, trajectories, and activity locations affect their exposure to traffic related air pollution. In addition, the individual-level analysis allowed us to identify individuals who reduce and those who increase their exposure during their daily trajectories and activities compared to the air quality at their home location. Our results showed that individuals who live in densely populated areas may be exposed to higher concentrations while generating low levels of emissions throughout their daily travel. Furthermore, results of this study indicate that using an integrated emission dispersion model for the assessment of individual exposure offers the opportunity for detailed, dynamic analysis of exposure to air pollution. The findings are useful for planning applications by using the model system to evaluate the effects of various transport policy scenarios on air pollution and exposure. In the last part of this research, a unique application was developed that supports decision makers by providing information about the current and future states of air pollution as a result of transit investments. For this purpose, the year 2008 was chosen as the base year and a future horizon year was chosen (2031). The integrated modelling system was used to evaluate the impact of an extensive regional transit improvement strategy revealing reductions in NO2 concentrations and exposures.

Characterizing near-road air pollution using local scale emission and dispersion models and validation against in-situ measurements-- An Wang, MASc, 2016

Near-road concentrations of nitrogen dioxide (NO₂), a known marker of traffic-related air pollution, were simulated along a busy urban corridor in Montreal, Quebec using a combination of microscopic traffic simulation, instantaneous emission modeling, and air pollution dispersion. In order to calibrate and validate the model, measurements of NO₂ were conducted mid-block along four segments of the corridor. The four segments were chosen to be consecutive and yet exhibiting variability in road configuration and built environment characteristics. Roadside NO₂ measurements were also paired with on-site meteorological data collected using a portable meteorological station. In addition, traffic volumes, composition, and routing decisions were collected using video-cameras located at upstream and downstream intersections. Dispersion of simulated emissions was conducted for eight time slots and under a range of meteorological conditions using three different models with vastly different dispersion algorithms (OSPM, CALINE 4, and SIRANE). While the use of OSPM and SIRANE led to simulated NO₂ concentrations closer to measured concentrations on road segments with buildings on both sides, CALINE 4 led to a better match with measured data when the built environment involves open terrain.

Testing the robustness of land-use regression models for atmospheric nitrogen dioxide and ozone using data from fixed and mobile monitoring campaigns-- Laura Minet, MASc, 2016

The objective of this thesis is to validate land-use regression models developed based on fixed and mobile measurements of ambient nitrogen dioxide (NO₂) and ozone (O₃) concentrations. For this purpose, a mobile monitoring campaign was conducted in the summer of 2015 in Montreal. The pollutant levels of 1,411 road segments were measured. Using data from repeated visits at each segment (N_vis), various land-use regression (LUR) models were developed based on segments with N_vis greater than or equal to 4, 8, 12, 16 and 20. Exposure surfaces for the island of Montreal based on these models were also developed.

Previously, during the summer of 2014, a monitoring campaign had taken place at 76 fixed locations spread around Montreal using the same sensors to measure the same two pollutants. LUR models as well as associated exposure surfaces were developed, and compared to the results from summer 2015.

We observed that the exposure surfaces resulting from both campaigns were highly dissimilar, and several possible explanations can be suggested. LUR models based on segments with a small number of repeated observations are associated with poor coefficients of determination (R²) and the exposure surfaces derived from them are poorly correlated with the summer 2014 exposure surface. On the other hand, restricting the LUR models to the road segments with N_vis greater than or equal to 16 leads to higher R² values at the expense of poor predictive capability outside of the sample mainly due to the fact that as N_vis increases, the variability in segment attributes within the sub-sample decreases as those segments become more concentrated in the downtown area.

This study highlights the sensitivity of LUR models based on mobile monitoring campaigns to the number of visits per segment and to the location of the segments and stresses the importance of careful design of outdoor data collection campaigns.

Capturing the effects of urban drive cycles and passenger ridership on transit bus emissions and investigating the potential of emission reduction strategies-- Ahsan Alam, PhD, 2015

This research is motivated by the importance of reducing transit bus emissions in urban areas which can only be achieved after understanding the factors affecting transit bus emissions and exploring the effects of various emission reduction strategies. We started with understanding the emissions estimation methods currently embedded within emission inventory models followed by a validation of the most commonly used model in North America, the Motor Vehicle Emissions Simulator (MOVES), in a local context by collecting instantaneous bus speed and passenger ridership data across a variety of transit routes (downtown and suburban/highway) and bus types (standard, articulated, old, and new). We then tested the effects of incorporating local drive cycles into the MOVES model illustrating the gains in accuracy that are achieved by replacing default drive-cycles with local ones. We analyzed the spatial and temporal variably of transit bus emissions across the island of Montreal and investigated the isolated and combined effects of different factors affecting emissions (including the level of congestion, roadway grade, passenger ridership, and traffic variability). We also investigated the reduction potential of different fuels including ultra-low sulfur diesel, compressed natural gas; and of transit service operational improvements including transit signal priority, queue jumper lane, and relocation of bus stops considering a wide combination of congestion, roadway grade, and passenger ridership. Finally, a corridor study was conducted to capture the changes in emissions as a result of the implementation of different transit service improvement strategies including smart card, express bus service, and reserved bus lane. In order to assess whether the emission reductions observed for transit buses could translate to passenger cars, we estimated passenger vehicle emissions in a large Montreal neighbourhood and investigated the potential of different emission reduction strategies. This thesis addresses critical gaps in the current knowledge of transit bus emissions, providing useful information to transit planners when implementing emission reduction strategies or modifying existing transit facilities.

Investigating the use of portable air pollution sensors to capture the spatial variability of urban air pollution-- Laure Deville-Cavellin, MASc, 2015

This thesis aims at developing air pollution exposure surfaces for nitrogen dioxide (NO₂) and ozone (O₃) in Montreal, Canada, using land use regression techniques, and thus capturing the effects of the built environment, traffic, and meteorology on the spatial variability of these two pollutants. Another objective of this work is to assess the potential of new handheld air quality sensors at capturing near-road air quality. To reach these objectives, we ran a data collection campaign on the island of Montreal, spanning 3 seasons (spring, summer and fall) in 2014. In total, 76 sites were identified and which represent the range of land-use and built environment characteristics in Montreal. Each site was visited at least 6 times throughout the campaign whereby measurements occurred for 30 minutes (per visit) with two O₃ and two NO₂ monitors. We also collected variables related to traffic and street characteristics on-site to assess their relationship with air pollution, and gathered a set of land-use and built environment characteristics at several buffer sizes around the sites (50, 100, 200, 300, 500, 750, 1000 m) using geographical information systems (GIS). The land use regression models we developed achieved R² values of 0.86 for NO₂ and 0.92 for O₃, when corrected for regional meteorology. Based on the coefficients of the NO₂ and O₃ models, we developed an exposure surface for each pollutant by applying the model in areas where air pollution data were not available. Our NO₂ surface is strongly correlated with older surfaces previously developed for Montreal, indicating that the spatial variability of air pollution has remained stable. Our O₃ model is to our knowledge the first of its kind and for this reason cannot be compared with previous results. The relationship between NO₂ and O₃ in our models, confirms our theoretical understanding of the behaviour of these pollutants. The exposure we generated in this study can be used for epidemiological studies in evaluating the associations between traffic related air pollution and health.

Influential Parameters of Near-Roadway Ultrafine Particles in Open Patio Spaces-- Alex Lee, MASc, 2015

The objective of this thesis is to identify factors related to meteorology and the built environment and its influence on near-roadway concentrations of ultrafine particles (UFP) in the context of restaurants and bars located within public open air spaces. The question that must be posed is how are variations in weather, traffic, on-site building characteristics impacting levels of UFP concentration, which in turn may produce adverse health effects for restaurant patrons as well as individuals working within hospitality industries.

To facilitate this study, a UFP monitoring campaign was organized and conducted during the months of May to July to measure at eight selected sites situated in Montreal, Canada. The eight study sites, chosen to reflect varying land use compositions and building characteristics, were each visited four times during lunch and dinner hours, where a site would be visited a total of two times (once per time period) during the weekday, and two times (once per time period) during the weekend. This campaign used meteorological information collected at the Montreal-Pierre Elliott Trudeau International Airport and at an automated weather station reporting from downtown Montreal. Traffic-related variables were derived from manual vehicle counts carried out at each study location, and the analysis of land use and other built characteristics relied on geographic information systems (GIS) data extracted from Transportation Research at McGill (TRAM), a transportation research group based at McGill University.

The investigation following the conclusion of the data collection campaign began by developing linear mixed effect models centred on variables relating to meteorology, traffic, site characteristics, and temporal factors. This data enables the validation of trends already defined in previous academic literature as well as to identify key findings that are contrary to intuitive hypotheses in the context of this study. Of note, meteorological effects such as temperature, wind speed, and wind direction relative to the orientation of the street are proven to possess inverse relationships with UFP. Homogeneity of land use is also an influential parameter and of significance with respect to this study of mixed use microenvironments. Furthermore, traffic-based predictors, most notably that of total diesel vehicles, contributed marginally to their concentrations.

The conclusions reached from this study, along with what is already known about ultrafine particles, allows for dialogue pertaining to optimizing the effectiveness of mixed use neighbourhoods from a health perspective in the context of open air patios. Provisional recommendations to improve the decision-making processes involved with planning and engineering such neighbourhoods are discussed and is critical for understanding the health and well-being of urban residents.

Investigating the effects of meteorology, built environment and traffic on near road air pollution-- Junshi Xu, MASc, 2015

This study aimed at capturing the determinants of near-road concentrations of ultrafine particles (UFP) using linear mixed-effects models, investigating the effects of meteorology, built environment, and traffic. In addition, the differences in the levels of UFP between both sides of the road were investigated. To reach these objectives, field measurements were conducted on 16 weekdays in the months of March and April 2015, along Papineau Avenue, a high-volume street in Montreal, Canada. Four sites were identified varying in land use, building height, and road characteristics. Air quality measurements were conducted at each location (on both sides of the road) for two consecutive hours, at four different times during the day and repeated four times, leading to a total of 16 visits per location. Traffic volume and composition was also recorded. On-site meteorological variables including wind speed, wind direction, temperature and relative humidity were collected using a portable weather station. Linear mixed-effects models with random intercept were developed for both dependent variables: the natural logarithm of the mean UFP concentration and the difference in UFP concentrations between two sides of the road. Lower temperatures and wind speeds were associated with increased UFP concentrations. Winds orthogonal to the road tended to increase UFP concentrations as well as the differences between both sides of the road. Finally, built environment variables such as the presence of open areas and buildings on both sides of the road, had a positive influence on the difference between UFP on the two sides.

Understanding the effects of the urban environment on cyclist exposure to near-roadway air pollution-- William Farrell, MASc, 2014

This thesis seeks to understand how the built environment and surrounding land use affect variations in near-roadway air pollution. In particular, two air pollutants are investigated: ultrafine particles (UFP) and black carbon (BC). Specifically, the study explores this question in the context of urban cycling. That is, how do factors such as traffic, buildings, and cycling infrastructure affect the concentration of air pollution to which cyclists are exposed?These answers are sought by way of a large-scale environmental monitoring campaign on the Island of Montreal during the summer of 2012. The campaign is comprised of two components: a mobile measurement portion whereby bicycles equipped with air pollution monitoring equipment cycle across roughly 500 km of unique roadway collecting UFP and BC concentrations, paired with global positioning system (GPS) data which allowed air pollution levels to be associated with the street on which they were collected—and a fixed site monitoring portion whereby research assistants measured pollution and counted traffic volumes and composition for set intervals of time at 73 locations. The overarching objective was to explain the variations in air pollution concentration by meteorological and built environment data, using land-use regression (LUR) analysis techniques. The mobile analysis relies primarily on geographic information systems (GIS) based land-use data while the fixed site analysis relies primarily on field measurements.Several investigations follow from this general data collection campaign. From the fixed site data a LUR model is developed based on meteorological factors, vehicular volumes and compositions, and built environment characteristics of the roadway corridor. These data also form the basis of a secondary investigation which explains the differences in UFP levels on opposite sides of the same street using wind, urban canyon, and traffic characteristics. Notable findings include support for some meteorological and urban canyon effects on air pollution, the relevance of both vehicular volumes as well as the truck component thereof.Two investigations arise from the mobile data collection campaign. The first attempts to explain the variations in air pollution using meteorological, land-use, and roadway characteristics, including results from a mesoscopic traffic simulation. The second seeks to understand how the nature of cycling infrastructure and cycling network design affect cyclists’ exposure to pollution. In addition to the effects captured in the fixed site analysis, relevant observations include the strong effects of nearby highways, especially for BC, and nearby restaurants, especially for UFP. The latter investigation from the mobile campaign shows that cycling facilities along major roads tend to have higher levels of pollution, however separated cycling infrastructure did reduce exposure to BC, perhaps owing in part from their greater distance from the street centerline. However the strongest reductions in air pollution were observed on multi-use trails, which typically run through parks and are located at substantial distances from the street.Together, these investigations use a novel methodological framework to unravel the interactions between cycling, the built environment, land use, traffic, and air pollution.

Development of an integrated transport and emissions model and applications for population exposure and environmental justice-- Timothy Sider, MASc, 2013

Road transport has a tremendous impact on local urban regions as well as global planetary health. This impact is especially great given the large quantities of greenhouse gases and local air pollutants released across the world, quantities that continue to increase. For metropolitan regions, reductions in traffic-related air pollution are paramount. Which baseline is used and which strategies should be implemented are both vital questions in this regard. Integrated transport and emissions models are important tools that aid metropolitan planners in answering those questions. A regional traffic assignment model has been connected to a detailed emission processor for the Montreal metropolitan region. The road transport model contains details on all private driving trips across a standard 24-hr workday, including congested link speeds and stochastic path distributions. Meanwhile, the emissions processor incorporates local vehicle registry data and Montreal-specific ambient conditions in the estimation of both running and start emissions. Outputs include hourly link-level and trip-level emissions for greenhouse gases, hydrocarbons, and nitrogen oxides. Three research studies were then explored that were anchored by the integrated transport and emissions model. The first involved testing model sensitivity to variations in input data and randomness. The second study was aimed at understanding the land-use and socioeconomic determinants of traffic-related air pollution generation and exposure. The third study encompassed an equity analysis of social disadvantage, traffic-related air pollution generation and exposure. Major findings include evidence that: start emissions and accurate vehicle registry data have the biggest impact on accurate regional emission inventories; neighbourhoods closer to downtown tend to be low emitters while having high exposures to traffic-related air pollution, while the opposite is true for neighbourhoods in the suburbs and periphery of the region; and marginalized neighbourhoods with high social disadvantage tend to have the highest exposure levels in the region, while at the same time generating some of the lowest quantities of traffic-related air pollution. These findings support the claim that traffic is creating environmental justice issues at the metropolitan level.

Investigating the effects of traffic calming on near-road air quality using traffic, emissions, and air dispersion modelling-- Golnaz Ghafghazi, MASc, 2013

This thesis focuses on the development of a microscopic traffic simulation, emission and dispersion modeling system which aims at quantifying the effects of different types of traffic calming measures on vehicle emissions both at a link-level and at a network-level and on air quality at a corridor level using a scenario analysis. The study area is set in Montréal, Canada where a traffic simulation model for a dense urban neighborhood is extended with capabilities for microscopic emission estimation and dispersion modeling. The results indicate that on average, isolated calming measures increase carbon dioxide (CO2), carbon monoxide (CO) and nitrogen oxide (NOx) emissions by 1.50%, 0.33% and 1.45%, respectively across the entire network. Area-wide schemes result in a percentage increase of 3.84% for CO2, 1.22% for CO, and 2.18% for NOx. Along specific corridors where traffic calming measures were simulated, increases in CO2 emissions of up to 83% are observed. These increases are mainly associated with a change in vehicle drive-cycles through increased accelerations and decelerations. The results for air quality modeling suggest on average NO2 levels increase between 0.1% and 10% with respect to the base case. A high positive correlation of 0.7 between segment emissions of NOx and concentrations of NO2 is observed. Also, the effects of wind speed and direction are investigated in this thesis. The results show that higher wind speeds decrease NO2 concentrations on both sides of the roadway while winds orthogonal to the road increase the difference between concentrations on the leeward and windward sides with the leeward side experiencing higher levels. The effect of different measures on traffic volumes is also investigated and moderate decreases in areas that have undergone traffic calming are observed. Finally, the results show that speed bumps result in higher emission levels and poorer near-roadway air quality than speed humps.

Publications

Journal Publications

2019

2018

2017

2016

2015

Farrell, W., S. Weichenthal, M. Goldberg, M. Hatzopoulou. 2015. Evaluating air pollution exposures across cycling infrastructure types: Implications for facility design. Journal of Transportation and Land-Use, 8 (3): 131-149.
Sider, T., M. Hatzopoulou, N. Eluru, G. Goulet-Langlois, K. Manaugh. 2015. Smog and socio-economics: An evaluation of equity in traffic-related air pollution exposure and generation. Environment and Planning B, 42: 870-887.
Farrell, W., L. Deville-Cavellin, S. Weichenthal, M. Goldberg, M. Hatzopoulou. 2015. Capturing the urban canyon effect on particle number concentrations across a large road network using spatial analysis tools. Building and Environment, 92: 328 -334.
Shekarrizfard, M., Y. Shamsunnahar, M.F. Valois, M. Goldberg, D. Crouse, N. Ross, M.E. Parent, M. Hatzopoulou. 2015. Investigating the role of transport models in epidemiologic studies of traffic related air pollution and health effects. Environmental Research, 140: 282-291.
Dale, LM., S. Goudreau, S. Perron, MS. Ragettli, M. Hatzopoulou, A. Smargiassi. 2015. Socioeconomic status and environmental noise exposure in Montreal, Canada. BMC Public Health, 15: 205.
Ghafghazi, G. and M. Hatzopoulou. 2015. Simulating the air quality impacts of traffic calming schemes in a dense urban neighbourhood. Transportation Research Part D, 35: 11-22.

2014

Sider, T., A. Alam, W. Farrell, M. Hatzopoulou, N. Eluru. 2014. Evaluating vehicular emissions with an integrated mesoscopic and microscopic traffic simulation. Canadian Journal of Civil Engineering, 41 (10): 856-868
Alam, A., G. Ghafghazi, M. Hatzopoulou. 2014. Traffic Emissions and Air Quality Near Roads in Dense Urban Neighborhood: Using Microscopic Simulation for Evaluating Effects of Vehicle Fleet, Travel Demand, and Road Network Changes. Transportation Research Record, No. 2427, pp. 83-92.
Weichenthal, S., M. Hatzopoulou, MS. Goldberg. 2014. Impact of short-term exposure to traffic-related air pollution during physical activity on blood pressure, autonomic and micro-vascular function in women. Particle and Fiber Toxicology, 11: 70
Alam, A., E, Diab, A. El-Geneidy, M. Hatzopoulou. 2014. A simulation of transit bus emissions along an urban corridor: Evaluating changes across several years and under various service improvement strategies. Transportation Research Part D, 31: 189-198.
Weichenthal, S., W. Farrell, L. Joseph, M. Goldberg^,M. Hatzopoulou. 2014. Characterizing the impact of traffic and built environment on near-road ultrafine particle concentrations. Environmental Research, 132: 305-310.
Alam, A. and M. Hatzopoulou. 2014. Investigating the isolated and combined effects of congestion, roadway grade, passenger loading, and alternative fuels on transit bus emissions. Transportation Research Part D, 29: 12-21.
Alam, A. and M. Hatzopoulou. 2014. Reducing transit bus emissions: Alternative fuels or traffic operations? Atmospheric Environment, 89: 129-139.
Ghafghazi, G., M. Hatzopoulou. 2014. Simulating the environmental effects of isolated and area-wide traffic calming schemes using traffic simulation and microscopic emission modeling. Transportation, 41 (3): 633-649.

2013

Sider, T., A. Alam, M. Zukari, H. Dugum, N. Goldstein, N. Eluru, M. Hatzopoulou. 2013. Land-use and socio-economics as determinants of traffic emissions and individual exposure to air pollution. Journal of Transport Geography, 33: 230-239.
Hatzopoulou, M., S. Weichenthal, G. Barreau, M. Goldberg, W. Farrell, D. Crouse, N. Ross. 2013. A web-based route planning tool to reduce cyclists’ exposures to traffic pollution: A case study in Montreal, Canada. Environmental Research, 123: 58-61.
Chan, L., Miranda-Moreno, Alam, A., M. Hatzopoulou. 2013. Assessing the impact of bus technology on greenhouse gas emissions along a major corridor: A lifecycle analysis. Transportation Research Part D, 20: 7-11.
Mathez, A., K. Manaugh, V. Chakour, A. El-Geneidy, M. Hatzopoulou. 2013. How can we alter our carbon footprint? Estimating GHG emissions based on travel survey information. Transportation, 40 (1): 131-149.
Hatzopoulou, M., S. Weichenthal, H. Dugum, G. Pickett, L. Miranda-Moreno, R. Kulka, R. Andersen, M. Goldberg. 2013. The impact of traffic counts and separate cycling lanes on personal air pollution exposures among cyclists in Montreal, Canada. Journal of Exposure Science and Environmental Epidemiology, 23 (1): 46-51.

2012

Strauss, J., L. Miranda-Moreno, D. Crouse, M. Goldberg, Ross, N., M. Hatzopoulou. 2012. Investigating the link between cyclist volumes and pollution levels along bicycle facilities in a dense urban core. Transportation Research Part D, 17 (8): 619-625.
Lau, J., M. Hatzopoulou, M. Wahba, E.J. Miller. 2012. An integrated multi-model evaluation of transit bus emissions in Toronto. Transportation Research Record, No. 2216, pp. 1-9.

2011

Hatzopoulou, M., J.Y., Hao, and E.J. Miller. 2011. Simulating the impacts of household travel on greenhouse gas emissions, urban air quality, and population exposure. Transportation, 38 (6): 871-887.

2010

Hao, J.Y., M. Hatzopoulou, and E.J. Miller. 2010. Integrating an activity-based travel demand model with dynamic traffic assignment and emission models: An implementation in the Greater Toronto Area. Transportation Research Record, No. 2176, pp. 1-13. Received the Charley V. Wootan Award for the Best Paper in Transportation Policy and Organization.
Hatzopoulou, M. and E.J. Miller. 2010. Linking an activity-based travel demand model with traffic emission and dispersion models: Transport’s contribution to air pollution in Toronto. Transportation Research Part D, 15 (6): 315-325.

2009

Hatzopoulou, M. and E.J. Miller. 2009. Transport policy evaluation in metropolitan areas: The role of modelling in decision-making. Transportation Research Part A, 43 (4): 323-338.

2008

Hatzopoulou, M. and E.J. Miller. 2008. Institutional integration for sustainable transportation policy in Canada. Transport Policy, 15 (3): 149–162.

2007

Hatzopoulou, M., E.J. Miller and B. Santos. 2007. Integrating vehicle emission modelling with activity-based travel demand modelling: A case study of the Greater Toronto Area (GTA), Transportation Research Record, No. 2011, pp. 29-39.
Kazopoulo M., I. Kaysi and M. El-Fadel. 2007. A stated-preference approach towards assessing a vehicle inspection and maintenance program. Transportation Research Part D, 12 (5): 358-370.

2001-2005

Kazopoulo M., M. El-Fadel and I. Kaysi. 2005. Emission standards development with exhaust emission measurements in a typical inspection and maintenance program. ASCE Journal of Environmental Engineering, 131 (9): 1330-1339.
El Fadel, M., I. Alameddine, M. Kazopoulo, M. Hamdan and R. Nasrallah. 2001. Indoor air quality assessment in an underground parking facility. Indoor + Built Environment, 10 (3-4): 179-184.
El Fadel, M., I. Alameddine, M. Kazopoulo, M. Hamdan and R. Nasrallah. 2001. Carbon Monoxide and Volatile Organic Compounds as indicators of indoor air quality in underground parking facilities. Indoor + Built Environment, 10 (2): 70-82.
Tabbal, M., M. Kazopoulo, T.C. Christidis and S. Isber. 2001. Enhancement of the molecular nitrogen dissociation levels by Argon dilution in surface wave sustained plasmas. Applied Physics Letters, 78: 2131.

Peer-Reviewed Conference Papers

Teaching

Course Code	Title & Description	Session	Day(s)	Start Time	End	Section
CIV1505H	Transportation Research Seminars Transportation Research Seminars This is a credit/non-credit seminar series that is mandatory for research students in the Transportation Research Group. This course does not count toward program course requirements. Talk to your supervisor for more information on how this course fits into your program.	Fall 2020	Friday	11:00	12:00	0101
CIV1505H	Transportation Research Seminars Transportation Research Seminars This is a credit/non-credit seminar series that is mandatory for research students in the Transportation Research Group. This course does not count toward program course requirements. Talk to your supervisor for more information on how this course fits into your program.	Winter 2021	Friday	12:00	13:00	0101
CIV1536H	Modelling Transport Emissions Modelling Transport Emissions	Not offered in 2020-2021				0101
CME261H	Engineering Mathematics I Engineering Mathematics I This course deals with both numerical methods for engineering analysis (solution of linear and non-linear equations, interpolation, numerical integration) and advanced topics in analytical calculus (multiple integrals and vector analysis). Within the numerical methods portion of the course emphasis is placed on problem formulation, solution algorithm design and programming applications. Within the analytical calculus portion emphasis is placed on the mathematical foundations of engineering practice and the interrelationship between analytical and numerical solution methods. Prerequisite: MAT188H1, MAT187H1. Exclusion: CIV261H1. View full course description in the Engineering Undergrad Academic Calendar.	Fall 2020	Scheduled by the Office of the Faculty Registrar.

Media

Modelling the health benefits of electric cars

Electric vehicles are often touted as a means of mitigating climate change, but a new modelling study suggests that their public health benefits may be just as significant. “Local air pollution within urban environments is highly detrimental to human health,” says Professor Marianne Hatzopoulou (CivMin), who led the research. “When you have an electric vehicle with no tailpipe emissions,… Read more »

CivMin students Alaa Itani and Junshi Xu among DiDi Graduate Awards

Two CivMin students are among ten University of Toronto graduate students who are receiving DiDi Graduate Awards in recognition of their contributions to the fields of artificial intelligence, vehicle autonomy, transportation analytics, human-machine interfacing and related topics. They are the first U of T students to receive scholarships from Beijing-based Didi Chuxing, the world’s… Read more »

A streetcar stops on King Street in Toronto. A section of the busy east-west street travelling through downtown Toronto has restricted car traffic, and U of T Engineering researchers are collaborating with the City of Toronto and the Toronto Transit Commission to study the pilot project’s effects. (Credit: Billy Cabic via Flickr under creative commons license)

Crunching the numbers on Toronto’s King Street transit pilot

Toronto’s King Street transit pilot project aims to improve transit reliability, speed and capacity, along with a number of other measures included in a comprehensive evaluation and monitoring program. For a team of researchers, it also presents an ideal opportunity to study the effects — both direct and indirect — of traffic changes on air and noise pollution,… Read more »