The 2025–2026 Iberian Atmospheric Rivers Exhibited Moisture Transport Resembling the Early SSP5‐8.5 Climate Response

Abstract Atmospheric rivers (ARs) drive winter hydroclimate extremes over the Iberian Peninsula (IP). This study evaluates whether exceptional landfalling ARs (LARs) between October 2025 and February 2026 displayed characteristics expected under early high‐emission forcing. High‐resolution WRF simulations forced by ERA5 and CESM2 under SSP5‐8.5 were used, using IPART for AR identification and FLEXPART‐WRF for moisture tracking. The simulated LARs reached vertically integrated water vapor transport magnitudes matching, and locally exceeding, those under the early SSP5‐8.5 climate response by 10%–15%. Mid‐tropospheric trough–ridge patterns enhanced zonal flow and long‐range moisture advection. Subtropical Atlantic moisture sources were 5%–20% stronger than simulated under the early SSP5‐8.5 response. LAR‐related precipitation over Atlantic‐facing IP sectors also matched or significantly exceeded ( p < 0.05) early SSP5‐8.5 levels. These results suggest that present‐day extreme ARs can generate moisture transport and hydrological impacts comparable to early transient high‐emission projections.