Climate change-induced floods disrupt intercity mobility in China: A national-scale assessment

Climate change-induced floods pose escalating threats to intercity mobility, undermining the sustainability and connectivity of national transport systems. This study develops an integrated assessment framework that combines large-scale hydrodynamic flood simulations, empirical intercity mobility data, and scenarios to quantify flood-induced transport disruptions across China. Results indicate that, under current conditions, road failures and mobility losses are concentrated in non-urban regions with sparse infrastructure and inadequate flood protection. Under future climate scenarios, both the intensity and spatial patterns of disruption shift. Urban agglomerations in eastern and southern China experience disproportionately large increases in mobility losses, driven by their centrality in the transport network and cascading vulnerabilities. Moreover, the dominant disruption mechanism shifts from indirect, connectivity-related losses to direct road failures, further amplifying system-wide fragility. These findings underscore a critical shift in intercity transport vulnerability under intensifying climate extremes and provide spatially differentiated insights to inform infrastructure adaptation and promote equitable transport planning.