Characteristics of the atmospheric vertical structure with different sea ice covers over the Pacific sector of the Arctic Ocean in summer

• Published in: Atmospheric research 2020-11, Vol.245 (C), p.105074, Article 105074
• Main Authors: Tian, Zhongxiang, Zhang, Dongqi, Song, Xiaojiang, Zhao, Fu, Li, Zhiqiang, Zhang, Lin
• Format: Article
• Language: English
• Subjects: Arctic Ocean; Inversion; Low-level jet; Radiosonde sounding; Sea ice
• ISSN: 0169-8095; 1873-2895
• DOI: 10.1016/j.atmosres.2020.105074

During the Chinese National Arctic Research Expedition in 2018 (CHINARE 2018), 84 radiosondes were released over the Pacific sector of the Arctic Ocean. Using these data, the characteristics of the atmospheric vertical structure with different sea ice covers were studied. The results showed that (1) typical temperature inversions were found in the low-level atmosphere with various characteristics over different regions. The inversions over the open water were the weakest and elevated. Oppositely, the inversions over the very pack ice zone were the strongest and located at the lowest altitude. Warm air advection, radiative cooling and surface melt together provided favorable conditions for the occurrence of an inversion over the very close pack ice zone. As a transition region, the marginal ice zone presented relatively moderate inversions that were mainly controlled by warm air advection and surface melt. (2) The upper-level jet over the very close pack ice zone was the weakest, and large differences were observed in the characteristics of low-level jets (LLJs) over different regions. With increasing sea ice, the frequency and strength of the LLJ increased and tended to enhance, respectively. Most LLJs were located below the tops of the inversions over the very close pack ice zone. Additional observation data are required to confirm that sea ice has significant impacts on the atmospheric vertical structure. •The upper-level jet over the very close pack ice zone was the weakest over different sea ice covers.•The inversions over the open water were the weakest and elevated.•The inversions over the very close pack ice zone were the strongest and located at the lowest altitude.•With increasing sea ice, the frequency of LLJs increased, and the strength of LLJs tended to enhance.