The Arctic Ocean Seasonal Cycles of Heat and Freshwater Fluxes: Observation-Based Inverse Estimates

Tsubouchi, Takamasa; Bacon, Sheldon ORCID: https://orcid.org/0000-0002-2471-9373; Aksenov, Yevgeny ORCID: https://orcid.org/0000-0001-6132-3434; Naveira Garabato, Alberto C.; Beszczynska-Möller, Agnieszka; Hansen, Edmond; de Steur, Laura; Curry, Beth; Lee, Craig M.. 2018 The Arctic Ocean Seasonal Cycles of Heat and Freshwater Fluxes: Observation-Based Inverse Estimates. Journal of Physical Oceanography, 48 (9). 2029-2055. https://doi.org/10.1175/JPO-D-17-0239.1

Before downloading, please read NORA policies.

Preview

Text jpo-d-17-0239.1.pdf Download (3MB) | Preview

Abstract/Summary

This paper presents the first estimate of the seasonal cycle of ocean and sea ice heat and freshwater (FW) fluxes around the Arctic Ocean boundary. The ocean transports are estimated primarily using 138 moored instruments deployed in September 2005–August 2006 across the four main Arctic gateways: Davis, Fram, and Bering Straits, and the Barents Sea Opening (BSO). Sea ice transports are estimated from a sea ice assimilation product. Monthly velocity fields are calculated with a box inverse model that enforces mass and salt conservation. The volume transports in the four gateways in the period (annual mean ± 1 standard deviation) are −2.1 ± 0.7 Sv in Davis Strait, −1.1 ± 1.2 Sv in Fram Strait, 2.3 ± 1.2 Sv in the BSO, and 0.7 ± 0.7 Sv in Bering Strait (1 Sv ≡ 106 m3 s−1). The resulting ocean and sea ice heat and FW fluxes are 175 ± 48 TW and 204 ± 85 mSv, respectively. These boundary fluxes accurately represent the annual means of the relevant surface fluxes. The ocean heat transport variability derives from velocity variability in the Atlantic Water layer and temperature variability in the upper part of the water column. The ocean FW transport variability is dominated by Bering Strait velocity variability. The net water mass transformation in the Arctic entails a freshening and cooling of inflowing waters by 0.62 ± 0.23 in salinity and 3.74° ± 0.76°C in temperature, respectively, and a reduction in density by 0.23 ± 0.20 kg m−3. The boundary heat and FW fluxes provide a benchmark dataset for the validation of numerical models and atmospheric reanalysis products.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	https://doi.org/10.1175/JPO-D-17-0239.1
ISSN:	0022-3670
Date made live:	13 Nov 2018 13:15 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/521492

Actions (login required)

View Item

Document Downloads

More statistics for this item...