Urban roughness is of major importance for understanding the wind dynamics and microclimate in an urban area. Morphometric methods are ideally suited for estimation of urban roughness in an urban environment due to increasing availability of 3D urban database, remote sensing and GIS (Geographical Information Systems). Frontal area is one of the key morphometric parameters required to compute roughness length (z0) and zero plane displacement height (zd). However the estimation of these morphometric parameters in a large area is computation intensive and complex. The advent of GIS and various open source computer technologies have eased the complexity of computation of these parameters. The present paper illustrates development of such an open source application, Urban Morphology Extractor (UME) and its deployment on a sample data. UME is a standalone application built using open source programming language Python and requires open source shapefile (.shp) data format for inputs and outputs. ME is a comprehensive application and is one of its kind, its capabilities include computation of frontal area using different criteria’s, computation of height-to-width ratio and generate shapefiles for eight different wind directions at user specified windline resolution. UME was tested over a sample dataset and overall accuracy of 92.5% and 90.3% was calculated for two wind direction for which computations were manually done.
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