Integrating Probabilistic Airborne Dispersion and Geospatial Vulnerability Assessment for Cascading Urban Radiological Hazards 



Reno Sudibyo

Indonesian Agency for Meteorological, Climatological and Geophysics, Kemayoran, Jakarta, Indonesia; and Disaster Management Study Program, Faculty of National Security, The Republic of Indonesia Defense University, Bogor, Indonesia


Pujo Widodo

Disaster Management Study Program, Faculty of National Security, The Republic of Indonesia Defense University, Bogor, Indonesia


Syamsul Maarif

Disaster Management Study Program, Faculty of National Security, The Republic of Indonesia Defense University, Bogor, Indonesia


Anwar Kurniadi

Disaster Management Study Program, Faculty of National Security, The Republic of Indonesia Defense University, Bogor, Indonesia


Demetrius Christian Hasaro

Indonesian Agency for Meteorological, Climatological and Geophysics, Kemayoran, Jakarta, Indonesia; and Sepuluh Nopember Institute of Technology, Surabaya, Indonesia



DOI: https://doi.org/10.19184/geosi.v11i2.60012 


Abstract 

Cascading airborne hazards in densely populated metropolitan areas pose major challenges for disaster risk reduction (DRR). This study developed a probabilistic geospatial framework to assess potential airborne radiological hazard propagation in the Bandung metropolitan area, Indonesia, under a hypothetical Iodine-131 (I-131) release scenario. Ensemble-based Gaussian puff simulations driven by ERA5 meteorological data were integrated with probabilistic exceedance mapping, demographic vulnerability analysis, district-level spatial aggregation, and healthcare infrastructure exposure assessment using Geographic Information System (GIS) approaches. The results identified elongated airborne exposure corridors across interconnected metropolitan districts within the Bandung Basin. High probabilistic exposure zones were concentrated near the southern urban source area and extended toward northern urban sectors. District-level analysis revealed that densely populated sub-districts and several healthcare facilities, including major hospitals, were located within elevated exposure zones. The study demonstrates the potential of probabilistic geospatial modelling to support uncertainty-aware urban DRR planning in rapidly urbanizing metropolitan environments.


Keywords:cascading disaster; airborne radiological hazard; probabilistic exceedance mapping; GIS; urban disaster risk reduction; Iodine-131