Do the Most Vulnerable People Live in the Worst Slums? A Spatial Analysis of Accra, Ghana

Annals of GISAnnals of GIS, Volume 17, Issue 4, 2011

Marta M. Jankowska, John R. Weeks, and Ryan Engstrom

“Slums are examples of localized communities within third-world urban systems representing a range of vulnerabilities and adaptive capacities. This study examines vulnerability in relation to flooding, environmental degradation, social status, demographics, and health in the slums of Accra, Ghana, by utilizing a place-based approach informed by fieldwork, remote sensing, census data, and geographically weighted regression (GWR). The study objectives are threefold: (1) to move slums from a dichotomous into a continuous classification and examine the spatial patterns of the gradient, (2) to develop measures of vulnerability for a developing world city and model the relationship between slums and vulnerability, and (3) to assess if the most vulnerable individuals live in the worst slums. A previously developed slum index is utilized, and four new measures of vulnerability are developed through principal components analysis (PCA), including a novel component of health vulnerability based on child mortality. Visualizations of the vulnerability measures assess spatial patterns of vulnerability in Accra. Ordinary least squares (OLS), spatial, and GWR model the ability of the slum index to predict the four vulnerability measures. The slum index performs well for three of the four vulnerability measures, but is least able to predict health vulnerability, underscoring the complex relationship between slums and child mortality in Accra. Finally, quintile analysis demonstrates the elevated prevalence of high vulnerability in places with high slum index scores.”

Climate Change-related Vulnerabilities and Local Environmental Public Health Tracking through GEMSS: A Web-based Visualization Tool

Applied GeographyApplied Geography, Volume 33, April 2012

Adele Houghton, Natasha Prudent, James E. Scott III, Richard Wade, and George Luber


  • Platform for tracking local climate change environmental public health indicators.
  • Visualization of potential health, vulnerability impacts of climate change policy.
  • Vulnerability indicators primarily used existing, freely available data sources.

“Climate change will impact health through a variety of pathways – both direct and indirect. Identifying the specific link between climate-related hazards and vulnerability will require the integration of socio-environmental, meteorological, and health data. An enhanced monitoring and tracking system is critical for public health efforts to identify and reach populations vulnerable to climate-related hazards, mobilize resources, and inform local climate action policy to reduce climate-related health risks.

“In this paper we present a novel application of a geospatial tool that integrates multiple data sources, allowing for the streamlined visualization of environmental risk, socio-economic and demographic vulnerability, baseline mortality, and policy intervention measures. GEMSS (Geospatial Emergency Management Support System) is a browser-based application that is designed to assemble geospatial information from multiple local or remote sources in a common operating environment, allowing for multi-data visualization. Using vulnerability to extreme heat and heavy rainfall-induced flooding as climate impacts on health, we tested GEMSS’s capability as a multi-data platform to visually analyze spatial patterns of climate change environmental public health indicators at the local level. The selected indicators relied on socio-environmental and demographic vulnerability, health, policy, and weather data.

“The GEMSS system has the potential to support multiple goals including: a) the ongoing monitoring and assessment of climate-related vulnerability through visualization; b) providing policymakers with an open-source tool for understanding how vulnerable populations and the environment could be impacted by proposed climate action policies; c) tracking the ongoing status of climate change policies in reducing socio-environmental vulnerability; d) raising awareness among the general public about the links between climate change and public health; and, e) providing a basis for epidemiologic research (i.e., identifying gaps between climate and human vulnerability leading to hypotheses and hypotheses-testing).”