Prediction modeling of land surface temperature in relation to land cover dynamics and health risk perception analysis in barishal city of Bangladesh

Rapid urbanization has brought about rapid changes in land-use and land-cover (LULC) patterns, significantly affecting land surface temperatures (LST). This study uses GIS and remote sensing techniques to assess changes in LULC classes and their impacts on LST at the Barishal City Corporation (BCC) of Bangladesh. As summer is the season with the highest temperature, the study considered the months from March to July from 1998-2024. The key findings of this study reveal a substantial increase in the mean land surface temperature, increasing by 5.75°C from 1998-2024, with the highest temperature reaching 42°C in 2024. This increase in temperature was linked to an 11.29% expansion in built-up areas and a reduction in vegetation (4.8%) and agricultural land (3.8%). The correlation analysis results support these findings, as the NDBI is positively correlated with the LST, indicating that built-up areas tend to increase surface temperatures. In contrast, the NDWI is negatively correlated with the LST, suggesting that water presence helps lower temperatures. The relationship between the NDVI and LST is predominantly negative in the absence of water bodies, whereas the presence of water bodies tends to result in a positive correlation. Most built-up areas presented the highest temperatures over the years, ranging from 34°C to 42°C. Future projections indicate that if the current trend of urban expansion remains, approximately 5.89% of the BCC area is projected to experience temperatures exceeding 38°C by 2033, increasing to 7.93% of the area by 2042. In terms of health impacts, the study identified common risks such as heat stroke, respiratory problems, heat exhaustion, dehydration, diarrhea, and skin rashes, among which heat exhaustion (66.93%) was most prominent. Furthermore, in urban areas, children, elderly people, women, outdoor workers, and people living in tin-shed houses are more vulnerable to high temperatures. This study will help city planners and future stakeholders control the urban heat island effect and understand the side effects of concentrated settlements in the coastal area of Bangladesh.