Probabilistic hazard assessment: Application to geomagnetic activity

Probabilistic Hazard Assessment (PHA) provides an appropriate methodology for assessing space weather hazards and their impact on technology. PHA is widely used in geosciences to determine the probability of exceedance critical thresholds, caused by one or more hazard sources. has proved useful with limited historical data estimate likelihood specific impacts. also driven development empirical physical models, ensembles replace measured data. Here we aim highlight method community provide example how it could be used. In terms impact, thresholds might include Geomagnetically Induced Current a high voltage power transformer neutral, local pipe-to-soil potential particular metal pipe. We illustrate context applying twelve-year dataset Earth-directed solar Coronal Mass Ejections (CME), which relate that global three-hourly geomagnetic activity index Kp exceeds thresholds. call this “Probabilistic Geomagnetic Assessment”, PGHA. This simple but concrete method. find cumulative > 6−, 7−, 8− = 9o 0.359, 0.227, 0.090, 0.011, respectively, following observation CME, summed over all CME launch speeds source locations. According distribution, represents order magnitude increase priori exceeding these For lower results are somewhat distorted our exclusion coronal hole high-speed stream effects. The PHGA reveals probabilistic associations between location subsequent maximum operational forecasters.