Global Urban‐Rural Differences in Precipitation: Cities See More Light Rain But Milder Extremes

Ample evidence has shown that cities modulate regional hydrometeorology and hydroclimatology. Because different precipitation intensities have distinct hydrological and societal impacts, with light precipitation helping to alleviate urban heat and extreme precipitation often driving flood risks, it is important to understand whether and how urban effects vary with precipitation intensity. Based on global satellite‐based observations, we demonstrate that 70.1% of large cities experience increased light precipitation frequency, while 69.9% exhibit milder extreme precipitation magnitude than their rural counterparts. By further dividing the rural areas into upwind and downwind regions, we find that the frequency of light precipitation events is enhanced within cities, but such enhancements shift to the downwind rural areas as the precipitation intensity increases, notably for heavy precipitation (>20 mm) frequency and extreme precipitation indices. Moreover, we perform weather simulations with a real atmosphere and idealized land surface configuration, which reveal that urban surfaces modify the precipitation distribution with more areas of low precipitation intensity but a milder maximum precipitation intensity, consistent with satellite‐based observational results. The contrasting influence of cities on light and extreme precipitation suggests an underappreciated role of urbanization in improving local climate conditions.