Time Series Analysis of Urban Temperature in Kandy City, Sri Lanka with the Use of Satellite Remote Sensing

Abstract

Nowadays Rapid urbanization is the foremost swelling problem in society. The building layer growth and the vegetation layer reduction lead to acceleration of urban temperature within the time. This increasing phenomena identified as an Urban Heat Island (UHI) effect in most of the suburb areas. In Sri Lanka, there are several identical cities that affect UHI effect and Kandy city noted as one of highly affected area. Urban population increase, vehicle traffic growth, development of the building layer and industrialization which leaded to the urbanization in Kandy. Most of the major Sri Lankan rivers starting from this central fragile area and it’s well-known as the highly environmentally sensitive area. Nonetheless with the increase of urban population along with building and other infrastructure facilities it leads for high temperature surge. Due to the recent development projects in Kandy city, it missing green colour layer and in the other hand rapidly rise the brown colour layer. Remote sensing is the best platform for monitoring environmental sensitive problems time series and the Landsat satellite program is the most appropriate, reliable data source. Therefore in this study Landsat 8 images of 2015, 2016 and 2017 was used as the data sources. With use of Infra-Red (IR) band temperature analysed and Normalized Difference Vegetation Index (NDVI) and Normalized Difference Building Index (NDBI) indices provide information of decrease of vegetation and increase of building layer correspondingly. Rendering to the study, it reveals that temperature increase in each year and it has directly relationship with building layer.