Evaluation of the ‘Local Climate Zone’ classification scheme in Singapore

Abstract

The objective of this thesis is to evaluate the applicability of the Local Climate Zone (LCZ) classification system developed by Stewart and Oke (2012) to urban heat island research on the tropical island state of Singapore. The LCZ classification scheme will be deemed applicable if the study sites can be satisfactorily classified into individual zones with unique temperature regimes. Eight surface properties given by Stewart and Oke (2012) were quantified using GIS and site visits. Twelve study sites were classified into five LCZs through the creation of subclasses. Air temperature data obtained from fixed sensors are used to test if each LCZ possesses unique temperature regimes. Results show that none of the study sites correspond fully to a single LCZ class due to Singapore’s highly heterogeneous urban development, thereby necessitating the creation of subclasses to facilitate the classification. The classification process was further complicated by the lack of standardization of methods for the creation of subclasses. Temperature measurements revealed that unique temperature regimes are only present for densely built up LCZs (LCZ 13) located in the Central Business District (CBD) area and for LCZs with abundant vegetation (LCZ 9B) located within urban parks. Distinct temperature regimes are not found for the remaining LCZs classified, thus invalidating the LCZ scheme on its use in Singapore. These results are caused by the highly mixed urban landscape of Singapore and the low representativeness of study sites with respect to their LCZ class. To apply the LCZ scheme to Singapore satisfactorily, full standardization of classification methods (including for the usage of subclasses) and an adaptation of the system to the local context are required.