Heat, salt, and volume transports in the eastern Eurasian Basin of the Arctic Ocean from 2 years of mooring observations

• Published in: Ocean Science
• Main Authors: A. V. Pnyushkov, I. V. Polyakov, R. Rember, V. V. Ivanov, M. B. Alkire, I. M. Ashik, T. M. Baumann, G. V. Alekseev, A. Sundfjord
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2018
• Subjects: Geography. Anthropology. Recreation; G; Environmental sciences; GE1-350; Arctic; Arctic Ocean; Laptev Sea; laptev
• Online Access: https://doi.org/10.5194/os-14-1349-2018; https://doaj.org/article/5a58841f73574aeab811fcaee824ff9c

This study discusses along-slope volume, heat, and salt transports derived from observations collected in 2013–2015 using a cross-slope array of six moorings ranging from 250 to 3900 m in the eastern Eurasian Basin (EB) of the Arctic Ocean. These observations demonstrate that in the upper 780 m layer, the along-slope boundary current advected, on average, 5.1±0.1 Sv of water, predominantly in the eastward (shallow-to-right) direction. Monthly net volume transports across the Laptev Sea slope vary widely, from ∼ 0.3±0.8 in April 2014 to ∼ 9.9±0.8 Sv in June 2014; 3.1±0.1 Sv (or 60 %) of the net transport was associated with warm and salty intermediate-depth Atlantic Water (AW). Calculated heat transport for 2013–2015 (relative to −1.8 °C) was 46.0±1.7 TW, and net salt transport (relative to zero salinity) was 172±6 Mkg s −1 . Estimates for AW heat and salt transports were 32.7±1.3 TW (71 % of net heat transport) and 112±4 Mkg s −1 (65 % of net salt transport). The variability of currents explains ∼ 90 % of the variability in the heat and salt transports. The remaining ∼ 10 % is controlled by temperature and salinity anomalies together with the temporal variability of the AW layer thickness. The annual mean volume transports decreased by 25 % from 5.8±0.2 Sv in 2013–2014 to 4.4±0.2 Sv in 2014–2015, suggesting that changes in the transports at interannual and longer timescales in the eastern EB may be significant.