Low‐Intensity Precipitation Dominates Peninsular Spain (1961–2022)

Precipitation regimes across peninsular Spain have undergone a structural reorganisation toward low‐intensity dominance over the past six decades (1961–2022), driven by redistribution across intensity classes rather than monotonic changes in totals. These findings are derived from a dense observational network of 2096 rain gauges. Rather than focusing solely on precipitation totals or extremes, we introduce a redistribution‐based diagnostic framework that jointly evaluates precipitation frequency (RF) and volumetric contribution (RC) across the full intensity spectrum (P1–P99). Results reveal that the lowest percentiles (P1–P10) show widespread positive trends in both RF and RC, with up to ~60% of the territory exhibiting statistically significant increases, particularly during winter and fall ( p < 0.05). In contrast, upper percentiles (P90–P99) display predominantly negative RF trends and largely non‐significant RC changes, with significant declines affecting only < 15% of peninsular Spain. Breakpoint analysis identifies a consistent regime shift in the late 1980s to early 1990s, marking the onset of increases in light precipitation occurrence. Phase‐space diagnostics indicate that more than 50% of stations exhibit concurrent increases in both RF and RC of low‐intensity precipitation, confirming redistribution toward weaker precipitation regimes. Despite this national‐scale signal, localised intensification of heavy precipitation occurs along Mediterranean coastal regions. These findings indicate that precipitation change in peninsular Spain is primarily driven by redistribution across intensity classes rather than monotonic changes in totals, with potential implications for water resources, runoff generation and flood risk in Mediterranean hydroclimatic environments.