Relationships between remotely sensed surface parameters associated with the urban heat sink formation in Santiago, Chile

This work addresses the remotely sensed urban heat sink formation in Santiago City, Chile. The main aim was to analyse the relationship that surface temperature exhibits with land cover types, as well as with vegetation cover fraction, surface moisture and albedo of Santiago City and its rural surroundings. Information was extracted from the processing of Landsat Enhanced Thematic Mapper Plus ( ETM +) data. Surface temperature of the main land cover classes and correlation coefficients between surface temperature and the above- mentioned surface parameters were analysed. The results show that the hottest surfaces are mainly concentrated in the northern rural valley, wherein the predominance of bare or sparsely vegetated land covers determine a low vegetation cover fraction and surface moisture content. The correlation coefficients obtained confirm the higher warming rate that the rural valley exhibits in comparision with the city temperatures at the image acquisition time, which is one of the main causes of urban heat sink formation.