| 19 Jun 2026
An extended hazard interaction matrix for exploring multi-hazard complexity in data-scarce regions: An application to Kerala, India
Abstract. This paper extends the analysis of multi-hazard interrelationships beyond the primary focus on cascading and amplifying mechanisms, through the development of an evidence-based database in a data-scarce context. The methodology is applied to Kerala, India. To support interpretation, an adapted hazard interaction matrix was developed that extends existing frameworks by (i) incorporating a broader range of interaction mechanisms beyond traditional cascading and amplifying effects, and (ii) enabling representation of three-way hazard interactions, advancing beyond conventional pairwise depictions. The matrix was further enhanced to capture seasonal variation in interaction potential throughout the year. Drawing on academic literature, grey literature, and media sources, the database captures evidence for both well-documented and underreported hazards and their interactions, whether historically observed or theoretically possible. The final database contains evidence of 22 distinct hazard types across six hazard groups and 137 potential hazard interrelationships. Results indicate that, while cascading and disposition-alteration mechanisms dominate the interrelationships observed in Kerala, accounting for additional interaction mechanisms increases the number of identified interrelationships by 36 %. This suggests that restricting analyses to a limited subset of interaction types may not fully capture the region's multi-hazard complexity. The matrix was further enhanced to capture seasonal variation in interaction potential throughout the year. Incorporating seasonality reveals distinct temporal windows of elevated interaction potential shaped by monsoon rainfall and temperature variability. When applying seasonal filters, the number of potential interrelationships identified was reduced by approximately 6%. This study demonstrates that interaction-focused, seasonally informed frameworks can reveal multi-hazard dynamics that may otherwise be overlooked when analysing only a subset of hazard types and interaction mechanisms
Competing interests: At least one of the (co-)authors is a member of the editorial board of Natural Hazards and Earth System Sciences.
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