Compound Climate Risk: Diagnosing Clustered Regional Flooding at Inter-Annual and Longer Time Scales

This is the complete data repository for the journal article - "Compound Climate Risk: Diagnosing Clustered Regional Flooding at Inter-Annual and Longer Time Scales." Abstract - The potential for extreme climate events to cluster in space and time has driven increased interest in understanding and predicting compound climate risks. Through a case study of floods in the Ohio River Basin, we demonstrate that low-frequency climate variability can drive spatial and temporal clustering of risk of regional climate extremes. Long records of annual maximum streamflow from 24 USGS gauges are used to explore the regional spatiotemporal patterns of flooding and their associated large-scale climate modes. We find that the dominant time scales of flood risk in this basin are in the interannual (6-7 years), decadal (11-13 years), and secular bands and that different sub-regions within the Ohio River Basin respond differently to large-scale forcing. We show the leading modes of streamflow variability are associated with ENSO and with secular trends. The low-frequency climate modes translate into epochs of increased and decreased flood risk with multiple extreme floods or the absence of extreme floods, thus informing the nature of compound climate-induced flood risk. A notable finding is that the secular trend is associated with a east to west shift of the flood incidence and the associated storm track. This is consistent with some expectations of climate change projections