Factors affecting the subsurface aragonite undersaturation layer in the Pacific Arctic region. (October 2022)

• Record Type: Journal Article
• Authors: Mo, Ahra; Kim, Dongseon; Yang, Eun Jin; Jung, Jinyoung; Ko, Young Ho; Kang, Sung-Ho; Cho, Kyoung-Ho; Park, Keyhong; Kim, Tae-Wook
• Is Part Of: Marine pollution bulletin. Volume 183(2022)
• Publication Date: 2022-10
• Subjects: Arctic Ocean -- Atmospheric circulation -- Pacific-Arctic regions -- Aragonite saturation -- Beaufort gyre -- Ocean acidification; Marine pollution -- Periodicals; Marine Biology -- Periodicals; Water Pollution -- Periodicals; Mer -- Pollution -- Périodiques; Publications périodiques; Pollution des mers; Lutte antipollution; Electronic journals; 363.7394
• DOI: 10.1016/j.marpolbul.2022.114060
• Languages: English
• ISSNs: 0025-326X

Abstract

Abstract: This study evaluated interannual variation in the subsurface aragonite undersaturation zone (ΩAr<1 layer) in the Pacific Arctic Ocean, using data from the 2016–2019 period. The upper boundary (DEPΩ<1 UB ) of the ΩAr<1 layer generally formed at a depth where the contribution of corrosive Pacific water was approximately 98 %. The intensity of the Beaufort Gyre associated with freshwater accumulation mainly determined interannual variation in DEPΩ<1 UB, but the direction of its effect was opposite west and east of ~166°W. The lower boundary (DEPΩ<1 LB ) of the ΩAr<1 layer was generally found at a depth range where equal contributions of Pacific and Atlantic water were expected. An Atlantic-origin cold saline water intrusion event in 2017 caused by an anomalous atmospheric circulation pattern significantly lifted the DEPΩ<1 LB, thus the thickness of the ΩAr<1 layer decreased. Highlights: Freshwater content and mixing of Pacific water with Atlantic water determined the boundaries of aragonite undersaturation. The upper boundary deepened inside the Beaufort Gyre when anticyclonic circulation enhanced gyre intensity. The lower boundary was significantly lifted following an Atlantic-origin cold saline water intrusion event in 2017.