Publications

Bala, R; Prasad, R; Yadav, VP (2020). A comparative analysis of day and night land surface temperature in two semi-arid cities using satellite images sampled in different seasons. ADVANCES IN SPACE RESEARCH, 66(2), 412-425.

Abstract
Urban heat island (UHI) refers to the occurrence of very high temperature patches in urban areas with respect to surrounding rural areas. The behaviour of Land Surface Temperature (LST) with different land covers varies for day and night time in a given urban area. Therefore, an attempt has been made for the comparative analysis of the day and night LST in two semi-arid cities in India i.e. Ahmedabad and Gandhinagar using two Landsat 8 images (one for day and one for night time) for each city. The relations of day and night LST with three independent variables such as Normalized Difference Vegetation Index (NDVI), Normalized Difference Built-up Index (NDBI) and impervious surface fraction (ISF) were established using Landsat 8 data. Based on the relation of LST with indices, the combinations of indices were used for developing the models to improve the correlation of day and night LST with the land cover. The developed models improved the correlation of day and night LST with the combinations of indices as compared to the relation of LST with individual variables in semi-arid urban landscapes with reasonably good coefficient of determination (R-2) values of 0.63 in Ahmedabad and 0.79 in Gandhinagar for day time. The reasonably good values of R-2 were found to be 0.81 and 0.75 for Ahmedabad and Gandhinagar, respectively, for night time. The developed model was also evaluated using 12 MODIS satellite images i.e. six images of each city for the summer, post-monsoon and winter seasons (one for day and one for night time in each season). The results of the developed models showed high capability to explain LST in heterogeneous semi-arid urban area for both day and night time in the summer, post-monsoon and winter seasons in a year. However, the relations established in this study can further be investigated for other months and years to understand its significance for other dates in semi-arid urban areas. (C) 2020 COSPAR. Published by Elsevier Ltd. All rights reserved.

DOI:
10.1016/j.asr.2020.04.009

ISSN:
0273-1177