Corrigendum to “In situ observation of contour currents in the northern South China Sea: Applications for deepwater sediment transport” [Earth Planet. Sci. Lett. 430 (2015) 477–485]

Abstract. Internal solitary waves (ISWs) are typical large-amplitude nonlinear waves occurring in stratified oceans. The in situ observations of ISWs are needed to improve the regimes of nonlinear internal wave theories. There is violent mixing of water mass in the horizontal and vertical directions during the propagation of ISWs, which generally lasts for a short period at a fixed position. However, an underwater glider, with the features of low-speed and sawtooth motion, cannot obtain a complete thermohaline stratification before and after the ISWs arrival. Those thermohaline data collected in situ by gliders, which vary synchronously at spatial-temporal scales, raise challenges for identifying the ISWs. Four Petrel-II gliders are deployed in the active region of ISWs in the South China Sea. This paper estimates vertical water velocity from glider flight data and kinematic model, analyzes the sensitivity of parameters in the glider kinematic model, and adopts a standard nonlinear search method to calibrate the parameters insensitive to the vertical velocity. The depth-keeping experiment is performed to verify the effectiveness of the optimized results. The standard deviation of vertical water velocity in the eastern Dongsha Atoll is revealed, and its distribution indirectly reflects that the strength of vertical water activity increases gradually at the same latitude along the east-west direction. Using observations of vertical water velocity fluctuations and isothermal surface vertical displacements, single- and multiple-wave packets can be identified. The availability of this method is tested by comparison with a MODIS image. Such an analysis provides a basis for the application of glider in the observation of ISWs.

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Toward a Mesoscale Hydrological and Marine Meteorological Observation Network in the South China Sea

Bulletin of the American Meteorological Society ◽

10.1175/bams-d-14-00159.1 ◽

2015 ◽

Vol 96 (7) ◽

pp. 1117-1135 ◽

Cited By ~ 26

Author(s):

Lei Yang ◽

Dongxiao Wang ◽

Jian Huang ◽

Xin Wang ◽

Lili Zeng ◽

...

Keyword(s):

South China Sea ◽

South China ◽

Dynamic Characteristics ◽

The South China Sea ◽

In Situ Observation ◽

Meteorological Observation ◽

The South ◽

China Sea ◽

Observation Network

Abstract Air–sea interaction in the South China Sea (SCS) has direct impacts on the weather and climate of its surrounding areas at various spatiotemporal scales. In situ observation plays a vital role in exploring the dynamic characteristics of the regional circulation and air–sea interaction. Remote sensing and regional modeling are expected to provide high-resolution data for studies of air–sea coupling; however, careful validation and calibration using in situ observations is necessary to ensure the quality of these data. Through a decade of effort, a marine observation network in the SCS has begun to be established, yielding a regional observatory for the air–sea synoptic system. Earlier observations in the SCS were scarce and narrowly focused. Since 2004, an annual series of scientific open cruises during late summer in the SCS has been organized by the South China Sea Institute of Oceanology (SCSIO), carefully designed based on the dynamic characteristics of the oceanic circulation and air–sea interaction in the SCS region. Since 2006, the cruise carried a radiometer and radiosondes on board, marking a new era of marine meteorological observation in the SCS. Fixed stations have been established for long-term and sustained records. Observations obtained through the network have been used to study regional ocean circulation and processes in the marine atmospheric boundary layer. In the future, a great number of multi-institutional, collaborative scientific cruises and observations at fixed stations will be carried out to establish a mesoscale hydrological and marine meteorological observation network in the SCS.

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In Situ Measurements and Comprehensive Research on the Present Crustal Stress of Northern South China Sea

Chinese Journal of Geophysics ◽

10.1002/cjg2.20117 ◽

2014 ◽

Vol 57 (4) ◽

pp. 462-473

Author(s):

CHEN Qun-Ce ◽

FAN Tao-Yuan ◽

LI Xu-Shen ◽

HE Sheng-Lin ◽

ZHANG Chong-Yuan ◽

...

Keyword(s):

South China Sea ◽

South China ◽

Northern South China Sea ◽

In Situ Measurements ◽

Crustal Stress ◽

China Sea

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The Wind Effect on Biogeochemistry in Eddy Cores in the Northern South China Sea

Frontiers in Marine Science ◽

10.3389/fmars.2021.717576 ◽

2021 ◽

Vol 8 ◽

Author(s):

Chun Hoe Chow ◽

Yung-Yen Shih ◽

Ya-Tang Chien ◽

Jing Yi Chen ◽

Ning Fan ◽

...

Keyword(s):

South China Sea ◽

South China ◽

Northern South China Sea ◽

Euphotic Zone ◽

Wind Effect ◽

Ocean Stratification ◽

China Sea ◽

Poc Flux ◽

Anticyclonic Eddies

Cyclonic and anticyclonic eddies are usually characterized by upwelling and downwelling, respectively, which are induced by eddy pumping near their core. Using a repeated expendable bathythermograph transect (XBT) and Argo floats, and by cruise experiments, we determined that not all eddies in the northern South China Sea (NSCS) were accompanied by eddy pumping. The weakening of background thermocline was attributed to the strengthening of eddy pumping, affected by (1) wind-induced meridional Sverdrup transports and (2) Kuroshio intrusion into the NSCS. Higher particulate organic carbon (POC) fluxes (> 100 mg-C m−2 day−1) were found near the eddy cores with significant eddy pumping (defined by a depth change of 22°C isotherm near the thermocline for over 10 m), although the satellite-estimated POC fluxes were inconsistent with the in-situ POC fluxes. nitrogen limitation transition and high POC flux were even found near the core of a smaller mesoscale (diameter < 100 km) cyclonic eddy in May 2014, during the weakening of the background thermocline in the NSCS. This finding provides evidence that small mesoscale eddies can efficiently provide nutrients to the subsurface, and that they can remove carbon from the euphotic zone. This is important for global warming, which generally strengthens upper ocean stratification.

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