Sea surface wind and cold tongue over the winter South China Sea

During summer, phytoplankton blooms occur frequently off the southeast Vietnam coast in the western South China Sea (WSCS). Using multi-source remote sensing data, such as sea surface temperature (SST), sea surface wind (SSW), aerosol optical thickness (AOT), sea level anomalies (SLA), and chlorophyll-a (Chl-a) data from 1998 to 2020 and in situ observations of analyzed data, we report the patterns of spatial variation of summer phytoplankton blooms in this region. The partial correlation and multiple stepwise linear regression analyses reveal that Ekman transport (ET) and Ekman pumping velocity (EPV) exert a greater impact on the summer phytoplankton blooms than the other environmental factors, suggesting that the phytoplankton blooms in the region may be mainly triggered by the enhanced nutrients by wind-induced upwelling and vertical mixing. AOT only weakly correlates with Chl-a concentration in the region, probably these prominent abundant nutrients in the region come from upwelling and convective-overturn. A northeastward jet causes the distribution of high Chl-a in the WSCS to be plume-shaped. A new finding in this study is that the northward current in this area may cause the northward deviation of phytoplankton blooms from the areas of upwelling.

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Analysis of surface chlorophyll a associated with sea surface temperature and surface wind in the South China Sea

Ocean Dynamics ◽

10.1007/s10236-019-01308-9 ◽

2019 ◽

Vol 70 (1) ◽

pp. 139-161 ◽

Cited By ~ 1

Author(s):

Hong-Ngu T. Huynh ◽

Aida Alvera-Azcárate ◽

Jean-Marie Beckers

Keyword(s):

South China Sea ◽

Surface Temperature ◽

Sea Surface Temperature ◽

Chlorophyll A ◽

South China ◽

Surface Wind ◽

The South China Sea ◽

Sea Surface ◽

The South ◽

China Sea

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Evaluation of HRCLDAS and ERA5 Datasets for Near-Surface Wind over Hainan Island and South China Sea

Atmosphere ◽

10.3390/atmos12060766 ◽

2021 ◽

Vol 12 (6) ◽

pp. 766

Author(s):

Yi Jiang ◽

Shuai Han ◽

Chunxiang Shi ◽

Tao Gao ◽

Honghui Zhen ◽

...

Keyword(s):

South China Sea ◽

South China ◽

Surface Wind ◽

Hainan Island ◽

The South China Sea ◽

Wind Data ◽

The South ◽

Near Surface ◽

China Sea

Near-surface wind data are particularly important for Hainan Island and the South China Sea, and there is a wide range of wind data sources. A detailed understanding of the reliability of these datasets can help us to carry out related research. In this study, the hourly near-surface wind data from the High-Resolution China Meteorological Administration (CMA) Land Data Assimilation System (HRCLDAS) and the fifth-generation ECMWF atmospheric reanalysis data (ERA5) were evaluated by comparison with the ground automatic meteorological observation data for Hainan Island and the South China Sea. The results are as follows: (1) the HRCLDAS and ERA5 near-surface wind data trend was basically the same as the observation data trend, but there was a smaller bias, smaller root-mean-square errors, and higher correlation coefficients between the near-surface wind data from HRCLDAS and the observations; (2) the quality of HRCLDAS and ERA5 near-surface wind data was better over the islands of the South China Sea than over Hainan Island land. However, over the coastal areas of Hainan Island and island stations near Sansha, the quality of the HRCLDAS near-surface wind data was better than that of ERA5; (3) the quality of HRCLDAS near-surface wind data was better than that of ERA5 over different types of landforms. The deviation of ERA5 and HRCLDAS wind speed was the largest along the coast, and the quality of the ERA5 wind direction data was poorest over the mountains, whereas that of HRCLDAS was poorest over hilly areas; (4) the accuracy of HRCLDAS at all wind levels was higher than that of ERA5. ERA5 significantly overestimated low-grade winds and underestimated high-grade winds. The accuracy of HRCLDAS wind ratings over the islands of the South China Sea was significantly higher than that over Hainan Island land, especially for the higher wind ratings; and (5) in the typhoon process, the simulation of wind by HRCLDAS was closer to the observations, and its simulation of higher wind speeds was more accurate than the ERA5 simulations.

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