Karen E. Smoyer-Tomic

Food Deserts in the Prairies? Supermarket Accessibility and Neighborhood Need in Edmonton, Canada*

Abstract The U.S. and U.K. literatures have discussed “food deserts,” reflecting populated, typically urban, low-income areas with limited access to full-service supermarkets. Less is known about supermarket accessibility within Canadian cities. This article uses the minimum distance and coverage methods to determine supermarket accessibility within the city of Edmonton, Canada, with a focus on high-need and inner-city neighborhoods. The results show that for 1999 both of these areas generally had higher accessibility than the remainder of the city, but six high-need neighborhoods had poor supermarket accessibility. We conclude by examining potential reasons for differences in supermarket accessibility between Canadian, U.S., and U.K. cities.

Measuring Neighbourhood Spatial Accessibility to Urban Amenities: Does Aggregation Error Matter?

Neighbourhood spatial accessibility (NSA) refers to the ease with which residents of a given neighbourhood can reach amenities. NSA indicators have been used to inform urban policy issues, such as amenity provision and spatial equity. NSA measures are, however, susceptible to numerous methodological problems. We investigate one methodological issue, aggregation error, as it relates to the measurement of NSA. Aggregation error arises when, for the purpose of distance calculations, a single point is used to represent a neighbourhood, which in turn represents an aggregation of spatially distributed individuals. NSA to three types of recreational amenities (playgrounds, community halls, and leisure centres) in Edmonton, Alberta, Canada is used to assess whether aggregation error affects NSA measures. The authors use exploratory spatial data analysis techniques, including local indicators of spatial association, to examine aggregation-error effects on NSA. By integrating finer resolution data into NSA measures, we demonstrate that aggregation error does affect NSA indicators, but that the effect depends on the type of amenity under investigation. Aggregation error is particularly problematic when measuring NSA to amenities that are abundant and have highly localized service areas, such as playgrounds. We recommend that, when analyzing NSA to these types of amenities, researchers integrate finer resolution data to indicate the spatial distribution of individuals within neighbourhoods better, and hence reduce aggregation error.

Heat Wave Hazards: An Overview of Heat Wave Impacts in Canada

Extreme heat events are natural hazards affecting Canada and many other regions of the world. This paper presents an overview of the issues involved in defining heat waves and harmful hot weather events, followed by a spatial and historical overview of heat waves across Canada, and an assessment of heat wave adaptation potential in selected cities. The Prairies, Southern Ontario, and areas in the St. Lawrence River Valley of both Ontario and Quebec demonstrate the highest temperatures and most frequent occurrences of heat waves, with minimal effects in the North, Pacific Coast, and Maritimes. Montreal frequently experiences extreme heat, and based on its low air conditioning rates and older, high-density housing, it demonstrates limited potential for adaptation to heat events. A scientific assessment was done to identify the effects of heat waves on various sectors of Canadian life including agriculture, livestock, fisheries, construction, transportation, utilities, the environment, and human health. Heat stress has been linked to excess human mortality and illness, violent behaviour, drought, forest fires, tornadoes, decreased agricultural and livestock productivity, construction and transportation difficulties, and reduced electrical power supply. Despite limited research on heat waves in Canada, this study demonstrates that the impacts of heat are profound and far-reaching.

The role of air pollution in the relationship between a heat stress index and human mortality in Toronto

In this study we considered confounding from air pollutants and chronological variables in the relation between humidex, a summer temperature and humidity index, and nonaccidental mortality, from 1980-1996 in Toronto, Canada. Changes in the risk of death by age group, gender, and combined cardiac-respiratory cause of death were estimated for both 1 degree C and 50-95th percentile increases in humidex using a generalized additive linear model. With air pollution terms in the models, relative risk (RR) point estimates narrowly exceeded 1.0 for all groups. Humidex effects were most apparent for females (RR=1.006, 95% CI=1.004-1.008 per 1 degree C humidex and RR=1.089, 95% CI=1.058-1.121 for 50th to 95th percentile humidex). When air pollution was omitted from the model, RR in the 50-95th percentile analysis increased less than 1.71% for all groups except females, for which RR decreased 1.42%. Differences in RR per 1 degree C humidex were all less than 0.12%. Confidence intervals narrowed slightly for all groups investigated. Heat stress has a statistically significant, yet minimal impact on Toronto populations, and air pollution does appear to have a small, but consistent confounding effect on humidex effect estimates.

Exploring Obesogenic Food Environments in Edmonton, Canada: The Association Between Socioeconomic Factors and Fast-food Outlet Access

Purpose. To explore the relationship between the placement of fast-food outlets and neighborhood-level socioeconomic variables by determining if indicators of lower socioeconomic status were predictive of exposure to fast food. Design. A descriptive analysis of the fast-food environment in a Canadian urban center, using secondary analysis of census data and Geographic Information Systems technology. Setting. Edmonton, Alberta, Canada. Measures. Neighborhoods were classified as High, Medium, or Low Access based on the number of fast-food opportunities available to them. Neighborhood-level socioeconomic data (income, education, employment, immigration status, and housing tenure) from the 2001 Statistics Canada federal census were obtained. Analysis. A discriminant function analysis was used to determine if any association existed between neighborhood demographic characteristics and accessibility of fast-food outlets. Results. Significant differences were found between the three levels of fast-food accessibility across the socioeconomic variables, with successively greater percentages of unemployment, low income, and renters in neighborhoods with increasingly greater access to fast-food restaurants. A high score on several of these variables was predictive of greater access to fast-food restaurants. Conclusion. Although a causal inference is not possible, these results suggest that the distribution of fast-food outlets relative to neighborhood-level socioeconomic status requires further attention in the process of explaining the increased rates of obesity observed in relatively deprived populations.

Synoptic weather patterns and modification of the association between air pollution and human mortality

Abstract To assess whether meteorological conditions modify the relationship between short-term exposure to ambient air pollution and mortality, an examination of air pollution and human mortality associations (ecologic) using hybrid spatial synoptic classification procedures was conducted. Concentrations of air pollutants and human mortality from all non-accidental and cardiorespiratory causes were examined according to typical winter and summer synoptic climatologies in Toronto, Canada, between 1981 and 1999. Air masses were derived using a hybrid spatial synoptic classification procedure associating each day over the 19-year period with one of six different typical weather types, or a transition between two weather types. Generalized linear models (GLMs) were used to assess the risk of mortality from air pollution within specific air mass type subsets. Mortality follows a distinct seasonal pattern with a maximum in winter and a minimum in summer. Average air pollution concentrations were similar in both seasons with the exception of elevated sulfur dioxide levels in winter and elevated ozone levels in summer. Subtle changes in meteorological composition can alter the strength of pollutant associations with health outcomes, especially in the summer season. Although there does not appear to be any systematic patterning of modification, variation in pollutant concentrations seems dependent on the type of synoptic category present.

Health Consequences of Drought on the Canadian Prairies

Population pressures and expanding agricultural and industrial development, with their resulting environmental degradation and demand for water, are likely to increase drought vulnerability on the Canadian Prairies. Coupled with increases in drought expected under climate change, the health and well-being of prairie populations may be compromised. However, little is known about the health effects of drought in this region or of possible adaptation strategies. This article assesses the available information on the health effects associated with drought and uses this information to develop an ecosystem health framework for outlining how drought may affect the prairie ecosystem and the health and well-being of Canadian Prairie populations. The article identifies multisector mitigation and adaptation strategies for reducing the harmful effects of drought on the prairie ecosystem and its populations. The literature review revealed that drought is associated with crop failure, increased atmospheric dust, and intensifying forest fire frequency, with health effects ranging from respiratory illnesses from inhaling dust or smoke, to mental health concerns arising from economic stress, particularly among farmers. Future research is needed on: the health effects associated with drought more specific to the Prairie region; the mental well-being of farmers and agricultural communities; the health effects from exposure to forest fire haze; and the health effects of reduced water supply and quality. Reducing drought vulnerability requires multisectoral collaboration, starting at the community level, to identify more sustainable water use, diverse health risks of drought, and ways of adapting to drought conditions.