Regional impervious surface estimation: an urban heat island application

This paper describes a GIS-based estimation method that can be used to forecast future amounts of impervious surface as a mitigation measure for urban heat island effect in a metropolitan region. The method is unique because it employs a regression model that links the existing amount of impervious surface to population and employment at the census tract level. This approach provides a means to forecast future amounts of impervious surface based on projected population and employment. The method also includes a detailed analysis of high-resolution aerial photography to divide impervious surfaces into different categories. Subdividing impervious surfaces is necessary to evaluate potential urban heat island mitigation policies for different types of impervious surface. The analysis here shows that the impervious surface in the metropolitan Atlanta region will increase to 2638 km2 2. “The Albedo is defined as the hemispherical reflectivity averaged over the solar spectrum. A perfect reflector has a = 1, and a perfect absorber has a = 0” (Pomerantz et al. 1999 Pomerantz, M. 1999. Reflective surfaces for cooler buildings and cities. Philosophical magazine B, 79: 1457–1476. [Taylor & Francis Online], [Web of Science ®] [Google Scholar], p. 1458). View all notes in 2030, an increase of 45% from 2000. The most common type of impervious surface is dark-coloured pavement. Within this study area, the analyses showed that two-thirds of impervious surfaces are dark. Replacing dark pavement with light pavement materials, therefore, represents an important opportunity to mitigate the urban heat island effect in the Atlanta region.     

The influence of race and gender on perceptions of community impact

Since 1968, research in public transportation planning has included an increasing number of analyses of the perceptions and attitudes of people who use and live in proximity to the systems (Nash and Hille 1968, McMillan et al. 1969, Wachs 1976). The results of the study reported here suggest that race and gender may explain more about attitudes toward the community impact of a transit system than do the levels of user satisfaction with the system. The implication for future research in this area is that surveys employing “satisfaction” and “importance” as indicators may not be using appropriate indices of evaluation. This study reports the results of a 1980 attitude survey of the perceptions of black and white men and women living within a two-block corridor along the Metropolitan Atlanta Rapid Transit Authority (MARTA) east line in Atlanta, Georgia. The research supports the Atlanta Regional Commission (ARC) Transit Impact Monitoring Program (TIMP). The survey used a stratified random sample technique to identify 100 households in which in-home interviews were subsequently conducted. A further stratified sampling procedure designated the gender and age of persons to be interviewed. The analysis included the isolation of responses by gender and race and used the chi-square statistic at the 0.05 significance level. The results identity differences in responses of males and females, blacks and whites.     

Modeling obsolete computer stock under regional data constraints: An Atlanta case study

In this paper, we report on our efforts to develop a research framework that can be used to quantify waste flows for different geographical areas in the face of limited waste data availability. We demonstrate this framework in our case study of obsolete computers in the Atlanta metropolitan area. We develop computer obsolescence rates at the national metropolitan level, and couple this data with economic information at the census tract level to generate product inventory estimates (PIE) of the stock of obsolete computers from both business and household sectors in the Atlanta metropolitan area. We seek to improve the accuracy of waste flow estimates for specific geographic areas over those of previous studies, provide an easily replicable and cost effective methodology, highlight the ensuing spatial implications for collection and recycling systems using GIS, and demonstrate the potential economic benefits from diverting electronic wastes within a region. The modeling framework we have developed is intended to be applicable to other regions and to other medium range durable goods discarded by households, businesses, or obtained from buildings.