Thinner Sea Ice Contribution to the Remarkable Polynya Formation North of Greenland in August 2018

• Published in: Advances in Atmospheric Sciences
• Main Authors: Shen, Xiaoyi, Ke, Chang-Qing, Cheng, Bin, Xia, Wentao, Li, Mengmeng, Yu, Xuening, Li, Haili
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer Science and Business Media LLC 2021
• Subjects: Atmospheric Science; Greenland; North Atlantic; North Atlantic oscillation; Sea ice
• Online Access: http://dx.doi.org/10.1007/s00376-021-0136-9; https://link.springer.com/content/pdf/10.1007/s00376-021-0136-9.pdf; https://link.springer.com/article/10.1007/s00376-021-0136-9/fulltext.html

Abstract In August 2018, a remarkable polynya was observed off the north coast of Greenland, a perennial ice zone where thick sea ice cover persists. In order to investigate the formation process of this polynya, satellite observations, a coupled ice-ocean model, ocean profiling data, and atmosphere reanalysis data were applied. We found that the thinnest sea ice cover in August since 1978 (mean value of 1.1 m, compared to the average value of 2.8 m during 1978−2017) and the modest southerly wind caused by a positive North Atlantic Oscillation (mean value of 0.82, compared to the climatological value of −0.02) were responsible for the formation and maintenance of this polynya. The opening mechanism of this polynya differs from the one formed in February 2018 in the same area caused by persistent anomalously high wind. Sea ice drift patterns have become more responsive to the atmospheric forcing due to thinning of sea ice cover in this region.