Anthropogenic amplification of the dynamics of large-scale contiguous extreme precipitation events

Large-scale contiguous extreme precipitation events severely disrupt societal functioning and exacerbate environmental vulnerability. The spatiotemporal continuity and dynamic evolution of individual extreme precipitation events remain poorly understood, often leading to reactive or inadequate disaster responses. Here we analyze 4630 global continental events exceeding 550,000 km2 during 1981–2020, using daily observational and model simulation data. This analysis uses a three-dimensional clustering algorithm with neighborhood connectivity from an event-based perspective. Results show that these events tend to occur in coastal regions of the low- and mid-latitudes and exhibit region-dependent directional movement. Over the past 40 years, they have become more extreme, with longer duration, higher intensity, wider coverage, and increased frequency, largely due to anthropogenic greenhouse gas emissions, although anthropogenic aerosols partially reduce the severity. Under global warming, most regions are expected to experience amplified events. Our findings provide critical scientific support and insights to mitigate global extreme precipitation disaster risks. Anthropogenic greenhouse gas emission drives the amplification of Large-scale contiguous extreme precipitation events especially in coastal regions of the low- and mid-latitudes, revealed by analyses on reanalysis data and model simulations.