Gis Modeling of Urban Components to Monitor and Model Urban Respiration

A Geographic Information System (GIS) is increasingly recognized as an effective tool for urban modeling. As a part of NASA's multidisciplinary project, this article develops GIS modeling methods of constructing measurements of urban components to monitor and model urban respiration. The first step is to create an Oracle database that stores spatially and temporally referenced measures of trace gases. Next, the measurements of land use, population density, roads, and wind are modeled and combined into a base grid cell matrix. Finally, spatial regression analysis is performed to estimate the effect of urban components on air quality. The usability of GIS in the context of environmental modeling is discussed. 1. Introduction The increasing urbanization and the emergence of megacities are prompting the need for the study of urban respiration, the interaction between urban activities and atmospheric chemistry. Urban activities consume atmospheric oxygen and expire carbon dioxide as well as various other trace gases and small particles. Although extensive research has been done to develop strategies to reduce air pollutants, the magnitudes and spatial-temporal dimensions of gaseous and aerosol pollutants and their relation to urban activities are not well known. This limited knowledge is partly due to the difficulty in examining the large and varied contents of the urban emissions, and partly due to the difficulty in measuring urban components.