A Study of Land Surface Temperature Variation in Selected Urban Cities in Sri Lanka

Abstract

Land Surface Temperature (LST) is one of the prominent methods to conduct climate studies and commonly used to analyze the impact of land surface changes all over the world. Due to many anthropogenic activities, natural environment transformed into urbanized areas rapidly. As a result, certain climatic components including land surface temperature has been modified dramatically. Therefore, this study was conducted to estimate Land Surface Temperature (LST) in highest population growth cities in Sri Lanka. The main objective of this research was to examine the relationship of rapid urban population growth with Land Surface Temperature using Geographical Information System (GIS) and Remote Sensing (RS) techniques. The study was conducted in five cities in Sri Lanka and those cities were selected by the population growth rate. Population data were collected from two census and statistic survey conducted in 2001 and 2011. The study has estimated Land Surface Temperature using Landsat TM, Landsat 8 data and spatial and temporal variations were also taken in to the consideration. Finally the study has revealed that the maximum LST values of the selected cities varied from 29 o C to 37 o C. When considering about spatial pattern of LST in 2005 and 2016 the highest mean LST were shown in Hambantota in 2005 and 2016. In 2005 mean LST has varied from 25 o C to 27 o C and in 2016 it was from 25 o C to 29 o C. LST has been increased with the population growth rate and land surface changes. However, some external factors such as meteorological, physical and environmental factors have influenced on the changes in LST in certain urban cities.