Assessment of social vulnerability under climate change risks in the southwestern coastal region of Bangladesh

ABSTRACT Significant changes in climatic elements will trigger social vulnerability and coastal community needs sustainable climate adaptation and risk reduction measures in coastal Bangladesh. Cyclones, storm surges, sea-level rise, tidal flooding, and limited adaptive capacity due to high population pressure and flat terrain make coastal Bangladesh highly vulnerable. This study assesses long-term climatic variability and household-level social vulnerability (SV) in Dacope Upazila, Khulna District, Bangladesh. Primary data were collected through semistructured household surveys using random sampling, while secondary climate data (1981–2021) were obtained from the NASA POWER database. The Mann–Kendall test was applied to evaluate the statistical significance of trends in rainfall and temperature, and Sen's slope method was used to estimate trend magnitude. Results indicate a downward trend in precipitation for January and February, with Z values of −0.096 and −0.042, respectively. Annual temperature also shows a decreasing trend (Z = −0.422). The rainfall anomaly index reveals that since 2015, values exceeding 1.3 indicate annual precipitation shifted from dry to extremely humid conditions. Future projections using global climate models suggest that maximum temperature may increase by 1–2 °C. SV was assessed using principal component analysis based on 28 indicators. The SV index score (+9.772) indicates high societal sensitivity to climate change. These findings can support policymakers in developing effective climate adaptation and disaster risk reduction strategies.