Using LULC trajectories to understand the relationship between LULC and land surface temperature of Bengaluru city
Student name: Ms Sabnam Kalita
Guide: Dr Nithiyanandam Yogeswaran
Year of completion: 2018
Host Organisation: TERI School of Advanced Studies
Abstract: This project adopts an approach to understand the relation between Land Surface Temperature and change in Land use and Land cover trajectory to examine the effects of urbanization over the city of Bengaluru. In this study, Landsat 5 TM and Landsat 8 OLI multispectral images have been used for 1998, 2007 and 2018 of Bengaluru City.
Firstly, the images were classified using supervised classification method followed by accuracy assessment. Secondly land use trajectories have been calculated based on classified images for different years. Then, the Land Surface Temperature (LST) were retrieved along with calculating mean surface temperature for each class with the help of the classified images to analyse the temperature contributed by each class in the study area. Finally, the indices such as Normalized Vegetation Index (NDVI) and Normalized Built up Index (NDBI) were calculated for each year so the correlation can be established between the indices and LST. The results demonstrate that land use trajectories are effective and useful in quantifying the effects of urbanization on UHI. In Bengaluru city, total 202 trajectories were found out of which 16 trajectories were showing details about existing urbanization whose trajectory code was 444 and urban growth which was other trajectory which is showing areas getting urbanized. The results of LST calculated values are fluctuating little bit because of unfavourable climatic and environmental conditions and lastly regarding the correlation part there was negative correlation among NDVI and LST and a positive correlation among NDBI and LST for all the years which is quite obvious because the city is getting urbanized every year. But the best part about this study area is that the vegetation is increasing and water bodies too and this is one of the reasons the temperature is bearable and pleasant. The overall study provides an alternate methodology to assess the heat island effects of urbanization and a decision support for planning and management of cities keeping in mind the need for thermal comfort of the residents and avoiding heat island effects from taking over the urban microclimate.
