The M2 Cotidal Chart in the Bohai, Yellow, and East China Seas from Dynamically Constrained Interpolation

2020 ◽  
Vol 37 (7) ◽  
pp. 1219-1229
Author(s):  
Junyong Zheng ◽  
Xinyan Mao ◽  
Xianqing Lv ◽  
Wensheng Jiang
Keyword(s):  
East China ◽  
Model Parameters ◽  
China Seas ◽  
The East China Sea ◽  
Satellite Altimeter ◽  
Constrained Interpolation ◽  
Marginal Seas ◽  
Shelf Sea ◽  
Dynamical Constraints ◽  
Adjoint Assimilation

AbstractThe harmonic constants extracted from tidal gauge stations and satellite altimeter observations are usually sparsely distributed in the continental marginal seas, but they are precious data for addressing the main characteristics of different constituents. In this paper, a dynamically constrained interpolation methodology (DCIM) is developed and applied to interpolate the observed harmonic constants of the M2 constituent from satellite altimeter observations in the Bohai, Yellow, and East China Seas (BYECS) with those from tidal gauge stations for validation. In the DCIM, the tide model provides dynamical constraints to interpolate the observations, and the adjoint assimilation method provides iterative optimization for the interpolated results by adjusting key model parameters. In particular, a substantial quantity of enhanced “observations” generated from the interpolated results of the domain are further interpolated with the sparse observations in the subdomain. The final interpolated results for each subdomain, naturally blending the dynamical constraints from the dynamical model with statistical information from observations, can describe the main characteristics of the M2 constituent in the BYECS, the continental shelf sea of the East China Sea, and the Zhejiang–Fujian coastal area, respectively. The results indicate that the DCIM is feasible and effective to utilize the observations to obtain high-accuracy cotidal charts for regional ocean.

scholarly journals Detrital Zircon U-Pb Ages in the East China Seas: Implications for Provenance Analysis and Sediment Budgeting

Minerals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 398
Author(s):  
Xiangtong Huang ◽  
Jiaze Song ◽  
Wei Yue ◽  
Zhongbo Wang ◽  
Xi Mei ◽  
...  
Keyword(s):  
East China Sea ◽  
Yellow Sea ◽  
Bohai Sea ◽  
East China ◽  
China Seas ◽  
Provenance Analysis ◽  
The East China Sea ◽  
The Bohai Sea ◽  
China Sea ◽  
Source Regions

Linking marine sinks to potential terrestrial sources is one of most intriguing but challenging aspects of sediment source-to-sink studies. In this study, we analyzed 23 zircon samples (3271 filtered best ages) from surface sediments of the east China seas (ECSs) that cover a large portion of the Bohai Sea, Yellow Sea, East China Sea to part of the northeastern South China Sea. The results of U-Pb age distributions exhibit variable signatures in different seas. The Bohai Sea is characterized by 4 age populations at 203–286 Ma, 383–481 Ma, 1830–1940 Ma and 2480–2548 Ma, whereas the southern Yellow Sea and the East China Sea are featured by 5 age populations at 176–223 Ma, 383–481 Ma, 732–830 Ma, 1830–1940 Ma and 2480–2548 Ma. We propose that the presence or absence of the population of 732–830 Ma in the Yangtze Craton (YC) and the North China Craton (NCC) is a possible geochronological signature to distinguish zircon grains derived from the two source regions. Furthermore, on the basis of multidimensional scaling (MDS), U-Pb ages in the sediments of the Bohai Sea, East China Sea and the Taiwan Strait could be correspondently linked to those of the Yellow River, the Yangtze River and Taiwan rivers. The good linkages support the view that U-Pb age distributions of detrital zircons in the margin seas are mainly controlled by fluvial discharges, and ultimately, by the tectonic history of the corresponding source regions. Using a sediment forward mixing model, we obtained the relative sediment contributions and spatial variations of five most important river discharges in the region. The mixing results suggest that the major rivers in the region, i.e., the Yangtze and the Yellow Rivers, are the dominant sediment contributors to the continental margin, and their mixing coefficients could be used to infer relative sediment budgeting. In addition, spatial variations in mixing coefficient in the East China Sea indicate that sediment mixing and partitioning processes in the marine depositional environment have played a part role in propagating the provenance signals as a result of interaction of oceanic currents and tides. The combined method between provenance analysis and mixing modeling provides a feasible way to appreciate sediment budgeting in the geological past.

Recent collections of sea spiders (Arthropoda: Pycnogonida) from China seas, with some new records and a checklist of the area

Zootaxa ◽  
2020 ◽  
Vol 4802 (2) ◽  
pp. 361-373
Author(s):  
JIANJIA WANG ◽  
HESHAN LIN ◽  
DINGYONG HUANG ◽  
XINQING ZHENG ◽  
QINGHE LIU ◽  
...  
Keyword(s):  
East China Sea ◽  
New Records ◽  
East China ◽  
China Seas ◽  
The East China Sea ◽  
Sea Spiders ◽  
China Sea

Though research about sea spiders limited in China seas, a complete checklist has not yet exist so far. After checking recent collections obtained from Shandong, Zhejiang, Fujian and the East China Sea, all these sixty-eight specimens were identified as six species belonged to four families and five genera, including three ones new to China. We described and illustrated them in this study, and also revised all previous records about Chinese pycnogonids and provided a checklist for the presently known forty-one species. 

scholarly journals Regional and Urban-Scale Environmental Influences of Oceanic DMS Emissions over Coastal China Seas

Atmosphere ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 849 ◽  
Author(s):  
Shanshan Li ◽  
Yan Zhang ◽  
Junri Zhao ◽  
Golam Sarwar ◽  
Shengqian Zhou ◽  
...  
Keyword(s):  
Bohai Sea ◽  
Regional Scale ◽  
The Yellow Sea ◽  
East China ◽  
China Seas ◽  
The East China Sea ◽  
Different Seasons ◽  
Fine Mode ◽  
Atmospheric Sulfur ◽  
Coastal China

Marine biogenic dimethyl sulfide (DMS) is an important natural source of sulfur in the atmosphere, which may play an important role in air quality. In this study, the WRF-CMAQ model is employed to assess the impact of DMS on the atmospheric environment at the regional scale of eastern coastal China and urban scale of Shanghai in 2017. A national scale database of DMS concentration in seawater is established based on the historical DMS measurements in the Yellow Sea, the Bohai Sea and the East China Sea in different seasons during 2009~2017. Results indicate that the sea-to-air emission flux of DMS varies greatly in different seasons, with the highest in summer, followed by spring and autumn, and the lowest in winter. The annual DMS emissions from the Yellow Sea, the Bohai Sea and the East China Sea are 0.008, 0.059, and 0.15 Tg S a−1, respectively. At the regional scale, DMS emissions increase atmospheric sulfur dioxide (SO2) and sulfate (SO42−) concentrations over the East China seas by a maximum of 8% in summer and a minimum of 2% in winter, respectively. At the urban scale, the addition of DMS emissions increase the SO2 and SO42− levels by 2% and 5%, respectively, and reduce ozone (O3) in the air of Shanghai by 1.5%~2.5%. DMS emissions increase fine-mode ammonium particle concentration distribution by 4% and 5%, and fine-mode nss-SO42− concentration distributions by 4% and 9% in the urban and marine air, respectively. Our results indicate that although anthropogenic sources are still the dominant contributor of atmospheric sulfur burden in China, biogenic DMS emissions source cannot be ignored.

Interannual variability of typhoon-induced northeast Asian marginal seas-mean sea level

2021 ◽  
Author(s):  
MyeongHee Han ◽  
SungHyun Nam
Keyword(s):  
Sea Level ◽  
East China Sea ◽  
East China ◽  
Interannual Variations ◽  
The East China Sea ◽  
Mean Sea Level ◽  
China Sea ◽  
Marginal Seas ◽  
Pass Through ◽  
Northeast Asian

<p><span>As connected through relatively narrow and shallow straits, inflow and outflow volume transports of the northeast Asian marginal seas (NEAMS) are strongly forced to yield significant convergence or divergence and resulting rise or drop in spatially-averaged sea level. Here, we examined interannual variations of August NEAMS-mean sea level observed from satellite altimetry from 1993 to 2019. Typhoon activity was found to be a primary factor controlling the interannual variations of NEAMS-mean sea level in August. Relatively high August sea level over the NEAMS is derived in years when more typhoons pass through the East China Sea (Period H) due to typhoon-induced Ekman transports. The resultant NEAMS-mean sea level is a few cm higher than that during the years of less or no typhoon activity in the East China Sea (Period L). This study highlights the importance of typhoon (hurricane) activity on interannual variations of regional sea level in the mid-latitude and semi-enclosed marginal seas.</span></p>

scholarly journals Using rare earth elements to constrain particulate organic carbon flux in the East China Sea

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Chin-Chang Hung ◽  
Ya-Feng Chen ◽  
Shih-Chieh Hsu ◽  
Kui Wang ◽  
Jianfang Chen ◽  
...  
Keyword(s):  
Rare Earth ◽  
Organic Carbon ◽  
Rare Earth Elements ◽  
Continental Shelf ◽  
Particulate Organic Carbon ◽  
East China Sea ◽  
Sediment Resuspension ◽  
East China ◽  
The East China Sea ◽  
Marginal Seas

Abstract Fluxes of particulate organic carbon (POC) in the East China Sea (ECS) have been reported to decrease from the inner continental shelf towards the outer continental shelf. Recent research has shown that POC fluxes in the ECS may be overestimated due to active sediment resuspension. To better characterize the effect of sediment resuspension on particle fluxes in the ECS, rare earth elements (REEs) and organic carbon (OC) were used in separate two-member mixing models to evaluate trap-collected POC fluxes. The ratio of resuspended particles from sediments to total trap-collected particles in the ECS ranged from 82–94% using the OC mixing model, and 30–80% using the REEs mixing model, respectively. These results suggest that REEs may be better proxies for sediment resuspension than OC in high turbidity marginal seas because REEs do not appear to undergo degradation during particle sinking as compared to organic carbon. Our results suggest that REEs can be used as tracers to provide quantitative estimates of POC fluxes in marginal seas.

scholarly journals Sea surface temperature (SST) anomalies of the Yellow and East China Seas in July of 2020

2021 ◽  
Vol 228 ◽  
pp. 02006
Author(s):  
Bin Wang ◽  
Lei Wu
Keyword(s):  
Heat Flux ◽  
Surface Temperature ◽  
Sea Surface Temperature ◽  
East China Sea ◽  
Sea Surface ◽  
East China ◽  
Westerly Wind ◽  
China Seas ◽  
The East China Sea ◽  
China Sea

With the global warming, the long term variations of sea surface temperature and its anomalies in the Yellow and East China Seas, especially for the July of 2020 due to the abnormally torrential rain along Changjiang/Yangtze River Valley, have been investigated based on the Merged Satellite and In-situ Data Global Daily sea surface temperature (MGDSST) provided by the Japan Meteorological Agency (JMA) using the methods of composite and correlation analyses. The results suggest, contrary to warming anomalies in the North-western Pacifica Ocean, the sea surface temperature in the East China Sea is cooler around 0.5°C and that in the East China Sea is cooler around 1.3°C than the normal values. The sea surface temperatures approach the extreme low value in the Yellow Sea and East China Sea in July, and warm up to the normal year in August. In addition, the south-westerly summer monsoon over this region, is proposed to contribute the transport of Kuroshio and its pathway. The obvious westerly wind anomalies, correspond to the lower sea surface temperature over the Yellow and East China Seas in July of 2020, leads to a clear less heat advection from Kuroshio to this region. Further, the low sea surface temperature, leading a downward air motion with a convergence at near sea surface level, is helpful for the enhance of the westerly wind anomalies until the strong surface heat flux in August. This study suggests that the local horizontal circulation advection and net heat flux are also dominated on the heat content of the East China waters. Further quantitative studies are worth conducting.

Sign in / Sign up

Export Citation Format

Share Document