Temporal Changes in Land Cover, Land Surface Temperature, Soil Moisture, and Evapotranspiration Using Remote Sensing Techniques-a Case Study of Kutupalong Rohingya Refugee Camp in Bangladesh

This study aims to assess the land use and land cover (LULC), land surface temperature (LST), soil moisture (SM), and evapotranspiration (ET) in the Kutopalong Rohingya refugee camp of the Cox's Bazar District in Bangladesh and compare the results to their surrounding areas to determine the changes for the duration of 2014-2019. A mix of indices and spatial algorithm-based remote sensing methodologies were applied on Landsat 8 satellite images to extract information on the mentioned surface components and processes. The empirical study suggests that since 2017 land use has become progressively diverse in pattern. A decrease of 6.16% in vegetation cover, respectively, with increased grassland and built-up by 5.13% and 1.79% for the whole of Cox's Bazar, has been observed during the 5 years. The significant changes are evident in the Kutupalong campsite alone, experiencing an 80.32% decrease in its total forest lands resulting from more than a four-time increase in Rohingya settlements within 2 years. With an overall accuracy of 87%, the findings are consistent with global LULC change patterns. Statistical and correlation analyses were used to explore the LST, SM, and ET. The results illustrate that the highly populated areas are associated with the highest LST and lowest ET, and vice versa. The maximum temperature observed is during the peak refugee intrusion period of 2017, ranging between 20.29-35.89 degrees C and 20.87-34.96 degrees C, respectively, for January and December. SM content was estimated for bare lands, and the obtained information indicates that dense human settlement directly and negatively impacts this variable. As a result, land in the entire Rohingya campsite is subject to a shift from moderate to mostly dry soil conditions. Evapotranspiration showed a linear trend with SM change and has decreased over the period.