GC Insights: Open R-code to translate the co-occurrence natural hazards into impact on joint financial risk

Hydro-meteorological hazard is often estimated by academic and public sector researchers using publicly funded climate models, whilst the ensuing risk quantification uses proprietary insurance sector models, which can inhibit the effective translation of risk-related environmental science into modified practice or policy. For co-occurring hazards, this work proposes as an interim solution open R-code that deploys a metric (i.e., inter-hazard correlation coefficient r) obtainable from scientific research, usable in practice without restricted data (climate or risk) being exposed. This tool is evaluated for a worked example that estimates the impact on joint financial risk at an annual 1-in-200 year level of wet and windy weather in the UK cooccurring rather than being independent, but the approach can be applied to other multi-hazards in various sectors (e.g. road, rail, telecommunications) now or in future climates.