A Review of the Definitions and Calculation Methods of Sky View Factor

The city, as a multifaceted phenomenon, has various dimensions. One of its most important dimensions, which has always been one of the debates raised in urban design and planning, is its geometry. Urban geometry and the geometry of urban valleys, which are defined by changes in height, length, and distance of buildings, significantly affect energy exchanges and thereby the temperature of urban areas. Changes in urban geometry will lead to some problems and issues, one of which is climate change on micro and medium scales. The geometry of the city has always been of interest to climatologists due to its effects on the urban climate. One of the important parameters of it is the Sky View Factor (SVF). Although urban climatologists know this factor well, it has not been properly raised among urban planners. On the other hand, since this factor is related to other climatic variables, it can play a key role in urban decision-making. Therefore, in the present study, it is attempted to present and classify the methods and techniques used for calculating this factor, while examining the need to pay attention to it. Therefore, this study aims to identify and study the types of this factor and then to study and classify various calculation and estimation methods. The results of this study show that the calculation and estimation of SVF have started with photographic and analytical methods and increasingly expanded with software and GPS methods. Also, at the end of this study, a classification of the background of the topic, along with various calculation methods and techniques and related software, is presented in a table in detail.