Observational evidence of increased extreme rainfall due to irrigation practice

Irrigation represents one of the most critical human interventions on the coupled water and energy cycles, driving substantial climate impacts via modifying surface energy balance and biogeochemical process. As irrigated farmland continues to expand, understanding the climate impact of extensive irrigation becomes increasingly important. Yet, the effect of irrigation on rainfall patterns, particularly extreme rainfall, at global scale remains poorly unclear. Here, using the “space-for-time” approach and global satellite precipitation datasets, we show that extreme rainfall events occur more often over irrigated lands than in surrounding rainfed areas. This signal is more pronounced in regions with more extensive irrigation, warmer temperatures, and higher precipitation. Our results improve mechanistic understanding of irrigation-precipitation interactions, which remain uncertain in climate and weather forecasting models.