Statistical analysis of diurnal variations in land surface temperature and the UHI effect using aqua and terra MODIS data
Shivam Chauhan, Ajay Singh Jethoo
Abstract
Natural and anthropogenic environmental changes are the key drivers in expansion of cities in the form of higher surface temperature than the expected one. This study aims to investigate the seasonality and homogeneity of surface temperatures in Indian city and its environs. To this end, we utilized day and night-time remote sensing data collected by Moderate Resolution Imaging Spectroradiometer (MODIS) sensor aboard the Aqua and Terra satellites from 2003 to 2020, encompassing the summer, monsoon and winter seasons. Our investigation reveals that the outskirts of urban centres experience significantly higher surface temperatures and more intense Urban Heat Indices (UHI) throughout the day. The temperature differential in the study area is consistently high throughout the year. Notably, both during the day and at night, the metropolitan areas of Ahmedabad city exhibit significantly higher temperatures than the surrounding rural regions. Furthermore, correlation analysis suggests that the most reliable results are obtained using the day-day and night-night combinations during the summer, monsoon and winter seasons, as opposed to the day-night and night-day combinations. These findings provide valuable insights into the thermal characteristics of urban regions, highlighting the need for appropriate mitigation strategies to combat the effects of UHI and promote sustainable development.