Cloud-mediated radiative and precipitation pathways link summer Arctic circulation modes to sea-ice melt variability

Summer Arctic sea-ice melt exhibits strong interannual and regional variability, yet the cloud-mediated pathways linking atmospheric circulation to melt remain poorly quantified. Using satellite observations, reanalysis data, and sea-ice products for 2000–2024, we examine the Arctic Oscillation (AO) and two dipole-like circulation modes, DA1 and DA2. These modes organize distinct altitude- and phase-dependent cloud anomalies and coherent responses in net, shortwave, and longwave cloud radiative effects. The net response is governed primarily by shortwave cloud–surface-albedo interactions, while longwave effects provide a weaker but regionally relevant contribution. Snowfall and rainfall also vary systematically and can modify the snow–ice surface state and albedo. Across nine Arctic subregions, diagnosed net energy-equivalent responses from LWCRE, cloud-related SWCRE, and albedo-related SWCRE range from −1.73 to 7.95 cm for AO, −8.22 to 4.95 cm for DA1, and −4.69 to 8.25 cm for DA2 per standard deviation. Comparison with the corresponding regional summer sea-ice thickness responses indicates that these pathways provide a measurable but partial modulation of melt variability. These results highlight the importance of cloud-radiative, surface-albedo, and precipitation-related processes for understanding and predicting regional Arctic sea-ice change.