Spatial distribution of heatwave vulnerability in a coastal city of Bangladesh

Abstract

While extreme heat events received wider attention in recent years, understanding heatwave vulnerability is still a challenging task that requires a clear understanding of a range of location-dependent climatic, socio-economic, physiological, and environmental parameters. This study investigates the spatial distribution of heatwave vulnerability in Chattogram City Corporation (CCC) — the commercial capital of Bangladesh. A heatwave vulnerability index (HVI) was developed, including various parameters related to three latent variables — exposure, sensitivity, and adaptive capacity — derived using remote sensing and socio-economic data. Factor analysis was performed to assess all parameters related to HVI. Besides, spatial autocorrelation, cluster and outlier analyses, and hot spot analysis were carried out to investigate the spatial distribution of HVI. This study shows a spatial distribution of HVI in CCC, which is spatially associated with various individual parameters. A total of seven wards (smallest administrative zone of CCC) were found to be very highly vulnerable to the heatwave. This study further reveals that heatwave vulnerability is randomly distributed throughout the city, although the high land surface temperature is concentrated in the existing built-up areas. It also identified three major hot spots of heatwave vulnerability in CCC. The methodology and findings of this study will be of interest to the policymakers and city planners to prepare mitigation plans, policies, and strategies to mitigate this hazard.