caa a22 4500 605546916 CHVBK 20210128100943.0 cr unu---uuuuu 210128e20150401xx s 000 0 eng 10.1007/s10236-015-0817-y doi (NATIONALLICENCE)springer-10.1007/s10236-015-0817-y Analysis of the northern South China Sea counter-wind current in winter using a data assimilation model [Elektronische Daten] [Jiping Xie, Jiang Zhu, Laurent Bertino, Francois Counillon] The South China Sea Warm Current (SCSWC) has drawn considerable attentions in the past decade due to its characteristic of flowing against the wind direction along the coast of Southeast China during winter. Observational monitoring of the SCSWC is yet insufficient to firmly assess of the property of this current. Prior modeling attempts have been carried out in idealized or simplified framework, e.g., coarse resolution, unrealistic wind forcing, artificial bathymetry, and/or missing dynamical processes. It is still unclear to what extent the above approximations may affect the properties of the SCSWC. In this study, a state-of-the-art data assimilation system of the South China Sea has been integrated from 1993 to 2005. The system uses the Hybrid Ocean Model (HYCOM) with tidal forcing and is forced with realistic atmospheric forcing. In order to ensure a more realistic positioning of the mesoscale features, the system assimilates along-track altimetry data with the Ensemble Optimal Interpolation (EnOI) to investigate the properties of the SCSWC for the period 1996-2005. The properties of the SCSWC in winter time are investigated and found: the current mainly follows the 100m isobaths and exists from immediately below the surface to the depth of 50m with a baroclinic structure; the main core is located at 20-30m depths and is composed of water warmer than the shelf water; and the width of the current is less than 100km. Meanwhile, based on the daily output, it was shown that the current is highly transient in January. Additional simulations without tidal forcing and without assimilation suggest that the transient property of the current is mainly driven by the atmospheric forcing while the mesoscale eddies enhance its variability. On the contrary, tidal forcing seems to reduce the strength of the SCSWC, as expected from tidal rectifying of the current. Springer-Verlag Berlin Heidelberg, 2015 South China Sea counter-wind current nationallicence Hybrid Coordinate Ocean Model nationallicence Tidal forcing nationallicence Ensemble Optimal Interpolation nationallicence Eddy kinetic energy nationallicence Xie Jiping Nansen Environmental and Remote Sensing Center, Bergen, Norway aut Zhu Jiang Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China aut Bertino Laurent Nansen Environmental and Remote Sensing Center, Bergen, Norway aut Counillon Francois Nansen Environmental and Remote Sensing Center, Bergen, Norway aut Ocean Dynamics Springer Berlin Heidelberg 65/4(2015-04-01), 523-538 1616-7341 65:4<523 2015 65 10236 https://doi.org/10.1007/s10236-015-0817-y text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10236-015-0817-y text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Xie Jiping Nansen Environmental and Remote Sensing Center, Bergen, Norway aut NATIONALLICENCE 700 1- Zhu Jiang Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China aut NATIONALLICENCE 700 1- Bertino Laurent Nansen Environmental and Remote Sensing Center, Bergen, Norway aut NATIONALLICENCE 700 1- Counillon Francois Nansen Environmental and Remote Sensing Center, Bergen, Norway aut NATIONALLICENCE 773 0- Ocean Dynamics Springer Berlin Heidelberg 65/4(2015-04-01), 523-538 1616-7341 65:4<523 2015 65 10236