The contribution of floods to streamflow at yearly timescales: A global assessment

Abstract

Much of the world's population faces significant threats to water security that are likely to be exacerbated under a warmer climate. To understand the impact of climate change on water security, we characterise the relationship between total annual streamflow, a surrogate for water supply, and low frequency flood events. We first calculate the proportion of annual streamflow attributable to flood events at approximately 5000 stations globally, then characterise this relationship as a function of climate and catchment characteristics. To explore the impact of climate changes we investigate trends in these relationships. We find that across the world on average 25% of annual streamflow comes f..