Flood maps alone are not sufficient to determine and assess the risks to people, property, infrastructure, and services due to a flood event. Simply put, the risk is almost zero to minimum if the flooded region is “empty” (i.e., unpopulated, has not properties, no industry, no infrastructure, and no socio-economic activity). High spatial resolution Earth Observation (EO) data can contribute to the generation and updating of flood risk maps based on several aspects including population, economic development, and critical infrastructure, which can enhance a city’s flood mitigation and preparedness planning. In this case study for the Don River watershed, Toronto, the flood risk is determined and flood risk index maps are generated by implementing a methodology for estimating risk based on the geographic coverage of the flood hazard, vulnerability of people, and the exposure of large building structures to flood water. Specifically, the spatial flood risk index maps have been generated through analytical spatial modeling which takes into account the areas in which a flood hazard is expected to occur, the terrain’s morphological characteristics, socio-economic parameters based on demographic data, and the density of large building complexes. Generated flood risk maps are verified through visual inspection with 3D city flood maps. Findings illustrate that areas of higher flood risk coincide with areas of high flood hazard and social and building exposure vulnerability.

The 3DTown project is focused on the development of a distributed system for sensing, interpreting and visualizing the real-time dynamics of urban life within the 3D context of a city. At the heart of this technology lies a core of algorithms that automatically integrate 3D urban models with data from pan/tilt video cameras, environmental sensors and other real-time information sources. A key challenge is the "three-dimensionalization" of pedestrians and vehicles tracked in 2D camera video, which requires automatic real-time computation of camera pose relative to the 3D urban environment. In this paper we report preliminary results from a prototype system we call 3DTown, which is composed of discrete modules connected through pre-determined communication protocols. Currently, these modules consist of: 1) A 3D modeling module that allows for the efficient reconstruction of building models and integration with indoor architectural plans, 2) A GeoWeb server that indexes a 3D urban database to render perspective views of both outdoor and indoor environments from any requested vantage, 3) Sensor modules that receive and distribute real-time data, 4) Tracking modules that detect and track pedestrians and vehicles in urban spaces and access highways, 5) Camera pose modules that automatically estimate camera pose relative to the urban environment, 6) Three-dimensionalization modules that receive information from the GeoWeb server, tracking and camera pose modules in order to back-project image tracks to geolocate pedestrians and vehicles within the 3D model, 7) An animation module that represents geo-located dynamic agents as sprites, and 8) A web-based visualization module that allows a user to explore the resulting dynamic 3D visualization in a number of interesting ways. To demonstrate our system we have used a blend of automatic and semi-automatic methods to construct a rich and accurate 3D model of a university campus, including both outdoor and indoor detail. The demonstration allows web-based 3D visualization of recorded patterns of pedestrian and vehicle traffic on streets and highways, estimations of vehicle speed, and real-time (live) visualization of pedestrian traffic and temperature data at a particular test site. Having demonstrated the system for hundreds of people, we report our informal observations on the user reaction, potential application areas and on the main challenges that must be addressed to bring the system closer to deployment.

Mental illness is a predominant medical condition in Canada. Marginalized groups in the Canadian population such as those with low income, the poorly educated and ethnic minorities are susceptible to mental health disorders. Using mental health-related emergency department visits as an indicator of mental illness cases, we employ a Bayesian spatio-temporal regression model to estimate mental illness risk across the 35 public health units of Ontario, Canada from 2006 to 2017. The association between mental illness and the following marginalization-related factors: material deprivation, residential instability and ethnic concentration is also evaluated. Over the assessed period, the relative risk of mental illness ranged from 0.45 (95% CI: 0.44–0.46) to 3.29 (95% CI: 3.20–3.37). Health units with elevated levels of material deprivation and residential instability were positively associated with increased mental illness risk whilst areas with higher ethnic concentration were linked with lower risk. Findings showed that the temporal trend of risk continuously increased over the 11 year period, with health units in northern Ontario experiencing higher risk compared to southern units. The management of psychiatric disorders presents a significant challenge to the Canadian health-care system. An understanding of the geographic distribution of mental health risk across space and time can be useful for improved policy-making and public health monitoring.

Canada has one of the highest incidence rates of brain cancer in the world. This study investigates the space–time variation of brain cancer risk across Southern Ontario, Canada. A Bayesian spatio-temporal regression model is used to estimate the relative risk of brain cancer in the 12 spatial health units of Southern Ontario over a four-year period (2010–2013). This work also explores the association between brain cancer and two potential risk factors: traumatic head injury (THI) and excess body fat (EBF). Across all areal units from 2010–2013, results show that the relative risk of brain cancer ranged from 0.83 (95% credible interval (CI) 0.74–0.91) to 1.26 (95% CI 1.13–1.41). Over the years, the eastern and western health units had persistently higher risk levels compared to those in the central areas. Results suggest that areas with elevated THI rates and EBF levels were also potentially associated with higher brain cancer relative risk. Findings revealed that the mean temporal trend for cancer risk progression in the region smoothly decreased over time. Overall, 50% of the health units displayed area-specific trends which were higher than the region’s average, thus indicating a slower decrease in cancer rates for these areas in comparison to the mean trend.