Rapid Arctic warming and sea ice loss have led to an intensification of the Arctic hydrological cycle, which is characterized by increased local evaporation and precipitation. Stable water isotopes as environmental tracers can provide useful insights into the Arctic hydrological cycle. However, the paucity of isotopic observations in the Arctic has limited our understanding of the hydrological changes. Here, we use an isotope-enabled atmospheric general circulation model (IsoGSM) combined with the Global Network of Isotopes in Precipitation (GNIP) observations to investigate the relationship between sea ice changes and Arctic precipitation d¹⁸O (d¹⁸O_p), and reveal the relative influence of local air temperature and evaporation on Arctic summer and winter d¹⁸O_p. We find that the Arctic d¹⁸O_p is negatively correlated with sea ice concentration, but positively with air temperature. Sea ice loss leads to enriched Arctic d¹⁸O_p through enhanced local evaporation and warming, but the relative importance of these processes varies between seasons. During summer, both local evaporation and warming contribute equally to d¹⁸O_p changes. In contrast, winter δ¹⁸O is predominantly driven by air temperature. This work improves our understanding of how Arctic precipitation isotopes respond to sea ice changes and has implications for the Arctic hydrological cycle and paleotemperature reconstructions.

北极迅速变暖和海冰消失导致北极水文循环加剧，其特点是局部蒸发和降水增加。稳定水同位素作为环境示踪剂可以为北极水文循环提供有用的见解。然而，北极同位素观测的缺乏限制了我们对水文变化的了解。在这里，我们使用同位素大气环流模型（IsoGSM）结合全球降水同位素网络（GNIP）观测来研究海冰变化与北极降水 d ¹⁸ O (d ¹⁸ O _p ) 之间的关系，以及揭示当地气温和蒸发对北极夏季和冬季 d ¹⁸ O _p的相对影响。我们发现北极 d ¹⁸ O _p与海冰浓度呈负相关，但与气温呈正相关。海冰损失通过增强局部蒸发和变暖导致北极 d ¹⁸ O _p丰富，但这些过程的相对重要性因季节而异。在夏季，局部蒸发和变暖对 d ¹⁸ O _p变化的影响相同。相比之下，冬季 δ ¹⁸ O 主要由气温驱动。这项工作提高了我们对北极降水同位素如何响应海冰变化的理解，并对北极水文循环和古气温重建具有影响。