Radiative climate feedbacks in the Arctic have been extensively studied, but their spatial and seasonal variations have not been thoroughly examined. Using ERA5 reanalysis data, we examine seasonal variations in Arctic climate feedbacks and their relationship to sea-ice loss based on changes from 1950–1979 to 1990–2019. The spring and summer seasons experienced large sea-ice loss, strong surface albedo feedback, and large oceanic heat uptake. Arctic clouds exerted small net cooling in May-June-July but moderate warming during the cold season, especially over areas with large sea-ice loss where cloud liquid and ice water content increased. Arctic water vapor feedback peaked in summer but was weak and uncorrelated with sea-ice loss. Arctic positive lapse rate feedback (LRF) was strongest in winter over areas with large sea-ice loss and weak inversion but uncorrelated with atmospheric stability, suggesting that oceanic heating from sea-ice loss led to enhanced surface warming and the positive LRF.

中文翻译：

---

ERA5 再分析中的北极气候反馈：季节和空间变化以及海冰流失的影响

北极的辐射气候反馈已被广泛研究，但其空间和季节变化尚未得到彻底研究。使用 ERA5 再分析数据，我们根据 1950-1979 年至 1990-2019 年的变化检查北极气候反馈的季节性变化及其与海冰损失的关系。春夏两季海冰流失大，地表反照率反馈强，海洋吸热大。北极云层在 5-6-7 月出现小幅净降温，但在寒冷季节温和升温，尤其是在海冰流失大的地区，云液和冰水含量增加。北极水汽反馈在夏季达到顶峰，但微弱且与海冰流失无关。