Divergent Impacts of Precipitation Regimes on Autumn Phenology in the Northern Hemisphere Mid‐ to High‐Latitudes

Climate change has altered precipitation regimes and shifted the end of the vegetation growing season (end of the season [EOS]), with consequences for terrestrial carbon and water cycles. However, the impacts of precipitation regimes, that is, total precipitation (Ptotal) and precipitation frequency (Pfreq), on EOS remain unclear. Using satellite‐derived phenology data from 1982 to 2020, we examined the effects of precipitation regimes on EOS across the mid‐ to high‐latitudes of the Northern Hemisphere. We found that both increased Ptotal and decreased Pfreq delayed EOS, with the effect of reduced Pfreq likely mediated through increased maximum temperature and elevated soil moisture resulting from higher precipitation intensity. We further developed a process‐based autumn phenology model that incorporated the effect of Pfreq, which significantly improved model performance. These findings underscore the influence of precipitation regimes on EOS and highlight the need to account for both precipitation frequency and intensity when projecting vegetation carbon uptake under future climate scenarios.