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Sample records for china sea

  1. South China Sea Challenge

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    China's attempts to solve disputes with ASEAN over the South China Sea help regional peace China's marine economy and security are currently faced with new challenges, requiring careful handling, especially in disputes with ASEAN countries and in promoting common development of the South China Sea. The outcome of how this is dealt with could undoubtedly pave the way for solutions to other oceanic disputes. The South China Sea is located south of

  2. South China Sea

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Chinese Foreign Minister Yang Jiechi warned against attempts to "in-ternationalize" the issue of the South China Sea, where China has territorial disputes with some ASEAN member states, including Viet Nam and the

  3. South China Sea.

    Science.gov (United States)

    Morton, B; Blackmore, G

    2001-12-01

    The South China Sea is poorly understood in terms of its marine biota, ecology and the human impacts upon it. What is known is most often contained in reports and workshop and conference documents that are not available to the wider scientific community. The South China Sea has an area of some 3.3 million km2 and depths range from the shallowest coastal fringe to 5377 m in the Manila Trench. It is also studded with numerous islets, atolls and reefs many of which are just awash at low tide. It is largely confined within the Tropic of Cancer and, therefore, experiences a monsoonal climate being influenced by the Southwest Monsoon in summer and the Northeast Monsoon in winter. The South China Sea is a marginal sea and, therefore, largely surrounded by land. Countries that have a major influence on and claims to the sea include China, Malaysia, the Philippines and Vietnam, although Thailand, Indonesia and Taiwan have some too. The coastal fringes of the South China Sea are home to about 270 million people that have had some of the fastest developing and most vibrant economies on the globe. Consequently, anthropogenic impacts, such as over-exploitation of resources and pollution, are anticipated to be huge although, in reality, relatively little is known about them. The Indo-West Pacific biogeographic province, at the centre of which the South China Sea lies, is probably the world's most diverse shallow-water marine area. Of three major nearshore habitat types, i.e., coral reefs, mangroves and seagrasses, 45 mangrove species out of a global total of 51, most of the currently recognised 70 coral genera and 20 of 50 known seagrass species have been recorded from the South China Sea. The island groups of the South China Sea are all disputed and sovereignty is claimed over them by a number of countries. Conflicts have in recent decades arisen over them because of perceived national rights. It is perhaps because of this that so little research has been undertaken on the

  4. South China Sea

    Energy Technology Data Exchange (ETDEWEB)

    Morton, Brian [Hong Kong Univ., Swire Inst. of Marine Science, Hong Kong (China); Hong Kong Univ., Dept. of Ecology and Biodiversity, Hong Kong (China); Blackmore, Graham [Hong Kong Univ. of Science and Technology, Dept. of Biology, Hong Kong (China)

    2001-07-01

    The South China Sea is poorly understood in terms of its marine biota, ecology and the human impacts upon it. What is known is most often contained in reports and workshops and conference documents that are not available to the wider scientific community. The South China Sea has an area of some 3.3 million km{sup 2} and depths range from the shallowest coastal fringe to 5377m in the Manila Trench. It is also studded with numerous islets, atolls and reefs many of which are just awash at low tide. It is largely confined within the Tropic of Cancer and, therefore, experiences a monsoonal climate being influenced by the Southwest Monsoon in summer and the Northeast Monsoon in winter. The South China Sea is a marginal sea and, therefore, largely surrounded by land. Countries that have a major influence on and claims to the sea include China, Malaysia, the Philippines and Vietnam, although Thailand, Indonesia and Taiwan have some too. The coastal fringes of the South China Sea are home to about 270 million people that have had some of the fastest developing and most vibrant economics on the globe. Consequently, anthropogenic impacts, such as over-exploitation of resources and pollution, are anticipated to be huge although, in reality, relatively little is known about them. The Indo-West Pacific biogeographic province, at the centre of which the South China Sea lies, is probably the world's most diverse shallow-water marine area. Of three major nearshore habitat types, i.e., coral reefs, mangroves and seagrasses, 45 mangrove species out of a global total of 51, most of the currently recognised 70 coral genera and 20 of 50 known seagrass species have been recorded from the South China Sea. The island groups of the South China Sea are all disputed and sovereignty is claimed over them by a number of countries. Conflicts have in recent decades arisen over them because of perceived national rights. It is perhaps because of this that so little research has been undertaken

  5. South China Sea: Controversies And Solutions

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Disputes have recently broken out between China and some Southeast Asian countries and the United States in the South China Sea. The Beijing-based Economic Information Daily spoke to Liu Nanlai, a research fellow at the Institute of International Law under the Chinese Academy of Social Sciences, on the origin of the South China Sea issue and China’s position on it. Excerpts follow:

  6. The South China Sea Deep: Introduction

    Science.gov (United States)

    Wang, Pinxian; Li, Qianyu; Dai, Minhan

    2015-12-01

    The South China Sea (SCS) has increasingly become a global focus in ocean research and hydrocarbon explorations. Over the last two decades, at least 17 international cruises including two ODP/IODP expeditions were conducted in the SCS, and more than 2000 exploratory wells were drilled (Wang et al., 2014a). While its sedimentary basins on the continental shelf and slope are explored for offshore resources, the deep basin below 3500 m in depth that overlies the basaltic oceanic crust preserves the key to understanding their formation and development. In order to better understand the life history and functional system of the marginal sea, a major research program "Deep Sea Processes and Evolution of the South China Sea", or "The South China Sea Deep" for short, was launched in January 2011 by the National Natural Science Foundation (NSFC) of China. This venture represents the first ever large-scale basic-research program in ocean science in the country (Wang, 2012).

  7. Ecological studies on Prochlorococcus in China seas

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Prochlorococcus, a tiny oxygenic photosynthetic picoplankton with unique pigment composition, has been found to be ubiquitous and abundant in the world oceans, and has been recognized to be closely related to living resources and environmental issues. It has attracted the interest of marine biologists since its discovery, and field data on it over global oceans have accumulated rapidly in the past 10 years. In China, we have studied Prochlorococcus for 8 years, achieving a basic ecological understanding. The presence of Prochlorococcus in China seas, marginal seas of the west Pacific, was confirmed, and its distribution patterns were also brought to light. Prochlorococcus is very abundant in the South China Sea and the offshore regions of the East China Sea. It is seasonally present in the southeast part of the Yellow Sea and absent in the Bohai Sea. Temporal and spatial variations of the abundance of Prochlorococcus and their affecting factors, physiological and ecological characteristics of Prochlorococcus and their relationships to the other groups of picoplankton, and the importance of Prochlorococcus in total biomass and possible roles in living resources and environmental problems are discussed. In the future, isolation of different Prochlorococcus strains from the China seas and their physiological characteristics, genetic diversity, phylogenies and gene exploiture, etc. are important issues to be addressed.

  8. Navigation Issues in the South China Sea

    OpenAIRE

    2005-01-01

    The South China Sea is one of the most important sea lanes with numerous competing sovereignty disputes. The freedom of navigation in this region is critical to all major trading States in the world. After an introduction to the navigational regimes of UNCLOS, this article describes the whole navigation situation in this region, by separately introducing the navigation issues in the territorial sea, straits, archipelagic waters and the Spratly area. Meanwhile, since the legal status of the ma...

  9. Deep-sea pollen research in China

    Institute of Scientific and Technical Information of China (English)

    SUN Xiangjun; LUO Yunli; CHEN Huaicheng

    2003-01-01

    This paper briefly presents the progress of deep-sea pollen research in China since the beginning ofninetieths of the last Century. All the deep-sea pollen contri-butions mainly come from the South China Sea (SCS) andthe East China Sea (ECS). The German-Chinese joint cruise(Sonne 95) and ODP 184 cruise initiated by Chinese scientistsin the SCS provided excellent material for the deep-sea pol-len research. So far a number of pollen results of 20-30 kaand million years from the SCS have been published. A couple of deep-sea pollen records from Okinawa Through of the ECS also came out. The high resolution pollen records obtained from the continuous deposits with high sedimentation rates and reliable age control of the deep-sea sediments provided a high time resolution history (hundred to millennial scales) of vegetation, environment and monsoon evolution of the pollen source areas (southern China and Japan). Spectral analysis of deep-sea pollen records from the SCS discovered orbital (100, 41, 23, 10 ka) and suborbital cyclicities (Heinrich and Dansgaard/Oscheger-O/D events) in the vege-tation changes. Moreover, cross spectral analysis showed that the trend of vegetation changes in northern SCS was regulated mainly by changes of the ice volume in the Northern Hemisphere. The pollen record of the last 20 ka from the Okinawa Through of the ECS indicates that the marine environmental change lagged that on the terrestrail by about 1000 year. The asynchronous environmental changes between land and sea were probably caused by the time difference in thermohaline circulation. This study underscored the role of the deep-sea plant fossils as a bridge across the land and sea.

  10. A Survey of Coral Reefs in South China Sea Completed

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ An investigation of coral reefs in South China Sea has recently completed by CAS scientists at South China Sea Institute of Oceanography (SCSIO) in Guangzhou. The compilation and analysis of the obtained data is now under way.

  11. Studies on Genus Cryptomonas from China seas

    Institute of Scientific and Technical Information of China (English)

    胡鸿钧; 李夜光; 吴莉平; 齐雨藻

    2002-01-01

    Six species of Genus Cryptomonas from the East and South China Seas are reported. C.varibilis H. J. Huet L. P. Wu, C. zhanjiangensis H. J. Huet L. P. Wu and C. zhejiangensis H. J. Hu et Y. G. Li are described as new. C. profunda Butcher, C. pseudobaltica Butcher and C. chrysoides Butcher are reported as new record.

  12. Sea surface temperatures and salinities from platforms in the Barents Sea, Sea of Japan, North Atlantic Ocean, Philippine Sea, Red Sea, and the South China Sea (Nan Hai) from 1896-1950 (NODC Accession 0000506)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Surface temperatures and salinities were collected in the Barents Sea, Sea of Japan, North Atlantic Ocean, Philippine Sea, Red Sea, and South China Sea (Nan Hai)...

  13. Characteristics of bivalve diversity in typical habitats of China seas

    OpenAIRE

    Fengshan Xu; Junlong Zhang

    2011-01-01

    With vast sea areas, long coastline and complex environmental conditions, the China seas contain various habitats for bivalves. The diversity characteristics of some typical habitats can reflect the molluscan fauna of China seas. Based on our years of work and records from malacologists home and abroad, the bi-valve diversity, habitats and ecological habits in different environments are described, and the distribution characters in different sea areas are analysed. Due to the effects of coast...

  14. A Note on the South China Sea Shallow Interocean Circulation

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The existing estimates of the volume transport from the Pacific Ocean to the South China Sea are summarized, showing an annual mean westward transport, with the Taiwan Strait outflow subtracted, of 3.5±2.0 Sv (1 Sv=106 m3 s-1). Results of a global ocean circulation model show an annual mean transport of 3.9 Sv from the Pacific to the Indian Ocean through the South China Sea. The boreal winter transport is larger and exhibits a South China Sea branch of the Pacific-to-Indian Ocean throughflow, which originates from the western Philippine Sea toward the Indonesian Seas through the South China Sea, as well as through the Karimata and Mindoro Straits. The southwestward current near the continental slope of the northern South China Sea is shown to be a combination of this branch and the interior circulation gyre.This winter branch can be confirmed by trajectories of satellite-tracked drifters, which clearly show a flow from the Luz6n Strait to the Karimata Strait in winter. In summer, the flow in the Karimata Strait is reversed. Numerical model results indicate that the Pacific water can enter the South China Sea and exit toward the Sulu Sea, but no observational evidence is available. The roles of the throughflow branch in the circulation, water properties and air-sea exchange of the South China Sea, and in enhancing and regulating the volume transport and reducing the heat transport of the Indonesian Throughflow, are discussed.

  15. Toxic Algae and Early Warning Management in Yellow Sea and Bohai Sea of China

    Institute of Scientific and Technical Information of China (English)

    Song; Lun; Song; Guangjun; Song; Yonggang; Xu; Xiaohong

    2014-01-01

    The research status of toxic algae in Yellow Sea and Bohai Sea are reviewed from the aspects of toxicity characteristics,toxic mechanism and early warning management,and the existing toxic algae and their toxicity in Yellow Sea and Bohai Sea are analyzed in the paper. The early warning level of toxic algae in Yellow Sea and Bohai Sea of China is put forward,and the research direction of shellfish poisoning in future is summarized.

  16. Comparison among four kinds of data of sea surface wind stress in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    谢强; 王卫强; 毛庆文

    2002-01-01

    By using remote sensing (ERS) data, FSU data, GOADS data and Hellerman & Rcsenstein objective analysis data to analyze the sea surface wind stress in the South China Sea, it is found that the remote sensing data have higher resolution and more reasonable values. Therefore we suggest that remote sensing data be chosen in the study of climatological features of sea surface wind stress and its seasonal variability in the South China Sea, especially in the study of small and middle scale eddies.

  17. Intensified Springtime Deep Convection over the South China Sea and the Philippine Sea Dries Southern China

    Science.gov (United States)

    Li, Zhenning; Yang, Song; He, Bian; Hu, Chundi

    2016-07-01

    Springtime rainfall, accounting for 25-40% of the annual rainfall in southern China, exerts great agricultural and socioeconomic impacts on the region. In the recent decades, southern China has experienced a significant declining trend of precipitation in boreal spring. Meanwhile, precipitation has increased over the South China Sea and the Philippine Sea (SCS-PhS). This paper presents observational and modeling evidences suggesting that the intensified latent heating released by the convection over SCS-PhS leads to suppressed springtime rainfall over southern China. Moisture budget analysis indicates that the drying trend over southern China is due mainly to weakened convergence of moisture flux, which is controlled by a heat-induced anomalous overturning circulation reinforced by the convection over SCS-PhS. Further idealized simulations support the feature that the heat-induced overturning circulation and its corresponding anomalous cyclone can be well established in several days under the spring mean flow condition. Thus, this rapid dynamic process is associated with both the intraseasonal-to-interannual variations and the long-term change of the springtime rainfall over southern China.

  18. Mineral Resources and Their Comprehensive Utilization in China Sea

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@It was said that mineral resources in oceans might be a reliable source for the material production. Ocean water is regarded as a huge “liquid deposit” for its ability to dissolve many kinds of elements. The total amount of elements in ocean water is greater than that in land. At the seafloor or below, occur a large number of mineral resources besides those in the water.China Sea, situated in the junction between North China block, Yangtze block and the Pacific plate and the Philippines plate, is excellent in ore-forming geological conditions, resulting in the presence of many kinds of deposits and abundant reserves. Mineral resources found in China Sea mainly include oil-gas resources, sea-beach placer and submarine coalfield.In addition, the manganese nodule and cobalt-rich crust are also discovered in South China Sea. Furthermore, the hydrothermal metalliferous deposit and gas hydrate may also be present in South China Sea.

  19. Distribution characteristics of marine litter on the sea bed of the East China Sea and the South Sea of Korea

    Science.gov (United States)

    Lee, Dae-In; Cho, Hyeon-Seo; Jeong, Sun-Beom

    2006-10-01

    The types, quantities, and distribution of marine litter found on the sea bed of the East China Sea and the South Sea of Korea are surveyed. Surveys were evaluated using bottom trawl nets during 1996-2005 cruises. Mean distribution densities were high in coastal seas, especially in the South Sea of Korea offshore from Yeosu, with 109.8 kg km -2, and low in the East China Sea, with densities of 30.6 kg km -2. Fishing gear, such as pots, nets, octopus jars, and fishing lines, accounted for about 42-72% and 37-62% of litter items in the East China Sea and the South Sea of Korea, respectively, whereas the contributions of rubber, vinyl, metal, plastic, glass, wood, and clothing were below 30% mainly. Rope and drum composition fluctuated greatly, between 54% and 0%. Eel and net pots dominated the marine debris of the South Sea of Korea, and some vinyl, plastics, and fishing gear made in Korea, China, and Japan were collected in abundance in the East China Sea. Fishing gear was probably discarded into the sea, deliberately or inadvertently, by fishing operations. A comprehensive joint approach by Korea, China, and Japan is needed for the continuous monitoring of input sources, the actual conditions, and the behavior of marine litter for protection against litter pollution and fisheries resource management in this area.

  20. New production in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    CAI; Pinghe

    2002-01-01

    estuary, Acta Oceanologica Sinica (in Chinese), 1993, 15(4): 50-55.[12]Okubo, T., Furuyama, K., Sakanoue, M., Distribution of 228Ra in surface sea water of the east Indian Ocean, Geochimica Journal, 1979, 13: 201-206.[13]Moore, W. S., Oceanic concentrations of 228Ra, Earth and Planetary Science Letters, 1969, 17: 437-446.[14]Sakanoue, M., Okubo, T., Furuyama, K., 228Ra in sea water, in Isotope Marine Chemistry (eds. Goldberg, E. D., Horibe, Y., Saruhashi, K.), Tokyo: Uchida Rokakuho Publishing Co. Ltd, 1980.[15]Dunne, J. P., Murray, J. M., Rodier, M. et al., Export flux in the western and central equatorial Pacific: Zonal and temporal variability, Deep-Sea ResearchⅠ, 2000, 47: 901-936.[16]Diego-McGlone, M. L. S., Jacinto, G. S., Dupra, V. C. et al., A comparison of nutrient characteristic and primary produc-tivity in the Sulu Sea and South China Sea, Acta Oceanographica Taiwanica, 1999, 37(3): 219-229.[17]Emerson, S., Quay, P., Karl, D. et al., Experimental determination of organic carbon flux from open-ocean waters, Nature, 1997, 389: 951-954.

  1. Cenozoic Volcanism in South China Sea and Its Vicinity and South China Sea Spreading

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The rock series, rock types and Sr-Nd isotopic dating of the Cenozoic volcanic rocks in the South China Sea are similar to those in its vicinity. On the basis of the spreading age of the South China Sea, the Cenozoic volcanic rocks are divided into three stages: the pre-spreading stage, the spreading stage and the post-spreading stage. The deep process characteristics of the asthenosphere and lithosphere may be inferred from the study on primary basaltic magma. The top layers of the asthenosphere both in the spreading stage and in the pre-spreading stage are closer to the earth surface than that in the post-spreading stage. From the pre-spreading stage to the spreading stage, the top layer of the asthenosphere decreased in depth, while the amount of interstitial partial melts increased. The evolution of the primary basaltic magma shows a progressive evolution sequence of the rifting volcanism and a faster lithospheric spreading velocity. From the spreading stage to the post-spreading stage, the top layer of the asthenosphere gradually increased in depth, but the amount of interstitial partial melts decreased. The evolution of primary basaltic magma shows a retrogressive evolution sequence of the rifting volcanism and a gradual decrease in the lithospheric spreading velocity. The depth recognized by the study on the Cenozoic volcanism demonstrates the deep environment for the formation and evolution of the South China Sea.

  2. A sea temperature data assimilation system for the China Seas and adjacent areas

    Institute of Scientific and Technical Information of China (English)

    YOU Xiaobao; ZHOU Guangqing; ZHU Jiang; LI Rongfeng

    2003-01-01

    A sea temperature data assimilation system for the China Seas and adjacent areas is developed based on a nested regional ocean circulation model and variational optimal interpolation assimilation method. A 12-year assimilation experiment is performed by using the observational temperature profiles from World Ocean Database 1998 (WOD98) and ECMWF reanalysis surface wind stress. Experimental results indicate that the variational scheme shows good skill in assimilating the observed sea temperature into a regional ocean circulation model. Compared with simulation alone, the sea temperature data assimilation significantly improves the performance of a regional ocean model and obtains comprehensive description of the circulations in the China Seas and adjacent areas. Assimilation results, such as the strength and flowing axis of the Kuroshio, Yellow Sea Cold Water Mass and its corresponding horizontal circulation in summer and dipole eddies in the South China Sea in the late summer/early autumn and the eastward jet between them, are well consistent with the observed evidences.

  3. Polycyclic aromatic hydrocarbons in sediments of China Sea.

    Science.gov (United States)

    Li, Yanxia; Duan, Xiaoyong

    2015-10-01

    Increasing pollution pressures were placed in the coastal and estuarine ecosystems in China because of the elevated pollutants discharged from various sources. Polycyclic aromatic hydrocarbons (PAHs) in the environment were closely linked to human activities, which have been intensively studied for their geochemical interest as markers. In this review, the status of PAH contamination in China Sea was assessed by comprehensive reviews of the concentrations, sources, and fates of PAHs in sediments of China Sea. PAH concentrations in China Sea sediments decreased from north to south due to the higher emissions in North China. Atmosphere was probably the main carrier of PAHs in the north due to the higher contents of atmospheric fine particles and higher wind speeds. However, riverine inputs were probably the most important sources of PAHs in the coastal sediments of South China due to higher rainfall.

  4. On Study of Sea Fog over the Yellow and Bohai Seas in China

    Science.gov (United States)

    Fu, G.; Gao, S.; Yang, Y.; Xu, X.; Wang, X.; Chen, Y.; Xue, D.; Shen, J.

    2010-07-01

    A ubiquitous feature of the Yellow and Bohai Sea (YBS) in the eastern Asian region is the frequent occurrence of the sea fog in spring and summer season. The pioneer work on sea fog over YBS can be traced back to Prof. Binhua Wang as early as 1940's. He investigated sea fog systematically and published his book Sea Fog in 1985 (by China Ocean Press and Springer-Verlag). Recently, a research group in the Department of Marine Meteorology at Ocean University of China (OUC) continued sea fog research collaborated with Shandong Meteorological Bureau and Qingdao Meteorological Bureau under the financial supports of National Natural Science Foundation of China and China Meteorological Administration. Their researches involved in both observation analyses and high-resolution modeling of sea fog over YBS. In this talk, the brief history of sea fog research in China will be reviewed firstly. Then, a typical heavy sea fog event over YBS occurred in the morning of 11 April 2004 will be documented by using all available observational data and high-resolution Regional Atmospheric Modeling System (RAMS) modeling results. Finally, the applications of a quasi-operational sea fog forecasting system which was mainly based on RAMS model will be introduced.

  5. Distributions of dimethylsulfide in the Bohai Sea and Yellow Sea of China

    Institute of Scientific and Technical Information of China (English)

    HU Min; TANG Xiao-yan; LI Jin-long; MA Qi-ju

    2003-01-01

    Dimethylsulfide(DMS) measurements in the surface seawater of China eastern coastline were conducted during March 9-10, 1993 in Bohai Sea along the cruise from Dalian to Tianjin and during September 24-25, 1994 in Yellow Sea along the cruise from Shanghai to Qingdao. On the cruise in Bohai Sea DMS concentrations varied from 0. 11 to 2.63 nmol/L with an average of 1.31 nmol/L, while DMS flux Bohai Sea. DMS concentrations and fluxes had a similar spatial trend both in Bohai Sea and Yellow Sea with the correlation coefficients of 0.75 and 0.64, respectively.

  6. Status of Marine Biodiversity of the China Seas

    OpenAIRE

    Liu, J. Y.

    2013-01-01

    China's seas cover nearly 5 million square kilometers extending from the tropical to the temperate climate zones and bordering on 32,000 km of coastline, including islands. Comprehensive systematic study of the marine biodiversity within this region began in the early 1950s with the establishment of the Qingdao Marine Biological Laboratory of the Chinese Academy of Sciences. Since that time scientists have carried out intensive multidisciplinary research on marine life in the China seas and h...

  7. High resolution bathymetry of China seas and their surroundings

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Based on the oceanic lithospheric flexure and the worldwide bathymetric data ETOPO5, the high resolu tion bathymetry of the China seas and their surroundings is computed from altimeter derived gravity anomalies. The new bathymetry obtained by this study is higher resolution and accuracy than the widely used ETOPO5 data, mean while it shows clearly the seafioor, the tectonic characteristics and the geodynamical processes in the China seas.

  8. Japan's Energy Policy on China:In the Perspective of Oil Dispute in East China Sea

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ Over recent years, the oil dispute in the East China Sea has become a new contradictory focus in Sino-Japanese relations after the issues of the Yasukuni Shrine and history text book. This article tries to take the oil dispute in the East China Sea as a penetrating point to analyze the basic line of thinking in Japan's China energy policy adjustment so as to better recognize the current situation and future of Sino-Japanese energy relations.

  9. KUROSHIO INTRUSION INTO THE SOUTH CHINA SEA

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qing-hua; FAN Hai-mei; QU Yuan-yuan

    2006-01-01

    In this article, the circulation of the South China Sea (SCS), which is idealized as the rectangular basin with constant depth, is studied under Kuroshio boundary forces. Starting from the linearly quasi-geostrophic vorticity equation, the solution of the SCS circulation is given in the form of corrected Fourier series under proper boundary conditions. The results show that the intruded current flows westward and separates into the northward branch and the southward branch before arriving at the western boundary. The southward branch flows out of the SCS through the southwestern passage, at the same time, the induced cyclonic (anti-clockwise) ring almost occupies the middle and southern parts, and concomitant anti-cyclonic (clockwise) vortex appears between the cyclone and the western boundary. While the northward branch outflows through the northeastern passage, the anti-cyclonic (clockwise) ring is triggered at the northern part of the SCS. The above two vortexes are both intensified if the south-entering and the north-leaving current loop intrusion are superposed. The outer flow of the northern vortex flows westward, then northward, and then eastward, and it is very similar to the configuration of the SCS Warm Current (SCSWC) at the northern part of the SCS, thus, a kind of generating mechanism of the SCSWC is presented.

  10. An improved algorithm of simulation on air-sea turbulent heat fluxes in China seas

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    With a global GSSTF2 and NCEP/NCAR reanalysis database and observation data at the Yong Xing station of Xisha Island in the South China Sea, we simulated the turbulent sensible and latent heat flux at sea surface in Chinese and neighboring seas (hereafter termed as China seas) using a common bulk method with some improved parameters. Comparing the simulated results with the observed and reanalyzed data, the improvement yielded higher accuracy, a smaller mean square deviation within 10 W/m2, and a smaller average relative error at about 25%. In addition, spatial resolution was improved to 0.1°×0.1°. The simulation is able to replay the main features of regional and seasonal variation in turbulent heat fluxes, and also the general pattern of heat flux changes during the summer monsoon outbreak in the South China Sea.

  11. Wind energy input in coastal seas east of China

    Institute of Scientific and Technical Information of China (English)

    ZANG Nan; WU Dexing

    2013-01-01

    This study investigates the wind energy input,an important source of mechanical energy,in the coastal seas east of China.Using the wind field from the high-resolution sea surface meteorology dataset in the Bohai Sea,Yellow Sea,and East China Sea,we studied the wind energy input through surface ageostrophic currents and surface waves.Using a simple analytical formula for the Ekman Spiral with timedependent wind,the wind energy input through ageostrophic currents was estimated at ~22 GW averaged from 1960 to 2007,and through use of an empirical formula,the wind energy input through surface waves was estimated at ~169 GW.We also examined the seasonal variation and long-term tendency of mechanical energy from wind stress,and found that the wind energy input to the East China Sea decreased before the 1980s,and then subsequently increased,which is contrary to what has been found for the Bohai Sea and Yellow Sea.More complicated physical processes and varying diffusivity need to be taken into account in future studies.

  12. Zooplankton community structure in the Yellow Sea and East China Sea in autumn

    Directory of Open Access Journals (Sweden)

    Hongju Chen

    2015-12-01

    Full Text Available Abstract Study on zooplankton spatial distribution is essential for understanding food web dynamics in marine ecosystems and fishery management. Here we elucidated the composition and distribution of large mesozooplankton on the continental shelf of the Yellow Sea and East China Sea, and explored the zooplankton community structure in these water masses. Sixty vertical hauls (bottom or 200 m in deep water to surface using a ring net (diameter 0.8 m, 505-μm mesh were exploited in November 2007. The biogeographic patterns of zooplankton communities were investigated using multivariate analysis methods; copepod biodiversity was analyzed using univariate indices. Copepods and protozoans were dominate in the communities. Based on the species composition, we divided the study areas into six station groups. Significant differences in zooplankton assemblages were detected between the Yellow Sea and East China Sea. Species richness was higher in East China Sea groups than those in Yellow Sea, whereas taxonomic distinctness was higher in Yellow Sea than in East China Sea. There was a clear relationship between the species composition and water mass group.

  13. Comparative study of SEA experiences between EU and China

    DEFF Research Database (Denmark)

    Gao, Jingjing; Kørnøv, Lone; Christensen, Per

    making, such as: How inclusive will the system be in relation to environmental, economic and social indicators? And how can the appropriate aggregation level for indicators be found? This paper makes a comparative study of the experiences of using indicators in SEA in two European countries and China...... SEA legislation and guidelines, this paper evaluates the different requirements related to indicator use within SEA in different national contexts. Furthermore, technical questions of how to design and use indicators in SEA are investigated. Finally, it is explored, from a political perspective, how...

  14. THE CLIMATE FEATURES OF THE SOUTH CHINA SEA WARM POOL

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    There exists a warm pool in the South China Sea (SCS). The temporal and spatial distribution and evolution of SCS warm pool is investigated using water temperatures at a depth of 20 m in the sea. The formation of the warm pool is discussed by combining water temperatures with geostrophic currents and simulated oceanic circulation. It is found that there are significant seasonal and interannual changes in the warm pool and in association with the general circulation of the atmosphere. The development of SCS warm pool is also closely related to the gyre activities in the sea and imported warm water from Indian Ocean (Java Sea) besides radiative warming.

  15. Status of marine biodiversity of the China seas.

    Directory of Open Access Journals (Sweden)

    J Y Liu

    Full Text Available China's seas cover nearly 5 million square kilometers extending from the tropical to the temperate climate zones and bordering on 32,000 km of coastline, including islands. Comprehensive systematic study of the marine biodiversity within this region began in the early 1950s with the establishment of the Qingdao Marine Biological Laboratory of the Chinese Academy of Sciences. Since that time scientists have carried out intensive multidisciplinary research on marine life in the China seas and have recorded 22,629 species belonging to 46 phyla. The marine flora and fauna of the China seas are characterized by high biodiversity, including tropical and subtropical elements of the Indo-West Pacific warm-water fauna in the South and East China seas, and temperate elements of North Pacific temperate fauna mainly in the Yellow Sea. The southern South China Sea fauna is characterized by typical tropical elements paralleled with the Philippine-New Guinea-Indonesia Coral triangle typical tropical faunal center. This paper summarizes advances in studies of marine biodiversity in China's seas and discusses current research mainly on characteristics and changes in marine biodiversity, including the monitoring, assessment, and conservation of endangered species and particularly the strengthening of effective management. Studies of (1 a tidal flat in a semi-enclosed embayment, (2 the impact of global climate change on a cold-water ecosystem, (3 coral reefs of Hainan Island and Xisha-Nansha atolls, (4 mangrove forests of the South China Sea, (5 a threatened seagrass field, and (6 an example of stock enhancement practices of the Chinese shrimp fishery are briefly introduced. Besides the overexploitation of living resources (more than 12.4 million tons yielded in 2007, the major threat to the biodiversity of the China seas is environmental deterioration (pollution, coastal construction, particularly in the brackish waters of estuarine environments, which are

  16. The Crustal Structure Character of East China Sea

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    This paper presents actuality of investigation and study of the crustal structure characters of East China Sea at home and abroad. Based on lots of investigation and study achievements and the difference of the crustal velocity structure from west to east, the East China Sea is divided into three parts - East China Sea shelf zone, Okinawa Trough zone and Ryukyu arc-trench zone. The East China Sea sheff zone mostly has three velocity layers, i.e.,the sediment blanket layer (the velocity is 5.8-5.9 km/s), the basement layer (the velocity is 6.0-6.3 km/s), and the lower crustal layer (the velocity is 6.8-7.6 km/s). So the East China Sea shelf zone belongs to the typical continental crust. The Okinawa Trough zone is located at the transitional belt between the continental crust and the oceanic crust. It still has the structural characters of the continental crust, and no formation of the oceanic crust, but the crust of the central trough has become to thinning down. The Ryukyu arc-trench zone belongs to the transitional type crust as a whole, but the ocean side of the trench already belongs to the oceanic crust. And the northwest Philippine Basin to the east of the Ryukyu Trench absolutely belongs to the typical oceanic crust.

  17. The Suspended Sediment Concentration Distribution in the Bohai Sea, Yellow Sea and East China Sea

    Institute of Scientific and Technical Information of China (English)

    BIAN Changwei; JIANG Wensheng; Richard J.Greatbatch; DING Hui

    2013-01-01

    The distribution of the suspended sediment eoncentration (SSC) in the Bohai Sea,Yellow Sea and East China Sea (BYECS) is studied based on the observed turbidity data and model simulation results.The observed turbidity results show that (i)the highest SSC is found in the coastal areas while in the outer shelf sea areas turbid water is much more difficult to observe,(ii) the surface layer SSC is much lower than the bottom layer SSC and (iii) the winter SSC is higher than the summer SSC.The Regional Ocean Modeling System (ROMS) is used to simulate the SSC distribution in the BYECS.A comparison between the modeled SSC and the observed SSC in the BYECS shows that the modeled SSC can reproduce the principal features of the SSC distribution in the BYECS.The dynamic mechanisms of the sediment erosion and transport processes are studied based on the modeled results.The horizontal distribution of the SSC in the BYECS is mainly determined by the current-wave induced bottom stress and the fine-grain sediment distribution.The current-induced bottom stress is much higher than the wave-induced bottom stress,which means the tidal currents play a more significant role in the sediment resuspension than the wind waves.The vertical mixing strength is studied based on the mixed layer depth and the turbulent kinetic energy distribution in the BYECS.The strong winter time vertical mixing,which is mainly caused by the strong wind stress and surface cooling,leads to high surface layer SSC in winter.High surface layer SSC in summer is restricted in the coastal areas.

  18. Long Term Sea Level Change and Water Mass Balance in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    RONG Zengrui; LIU Yuguang; ZONG Haibo; XIU Peng

    2009-01-01

    Sea level anomalies observed by altimeter during the 1993-2006 period, thermosterie sea level anomalies estimated by using subsurface temperature data produced by Ishii and SODA reanalysis data, tide gauge records and HOAPS freshwater flux data were analyzed to investigate the long term sea level change and the water mass balance in the South China Sea. The altimeter-observed sea level showed a rising rate of (3.5±0.9)mm yr-1 during the period 1993-2006, but this figure was considered to have been highly distorted by the relatively short time interval and the large inter-decadal variability, which apparently exists in both the thermosteric sea level and the observed sea level. Long term thermosteric sea level from 1945 to 2004 gave a rising rate of 0.15±0.06 mmyr-1. Tide gauge data revealed this discrepancy and the regional distributions of the sea-level trends. Both the 'real' and the thermosteric sea level showed a good correspondence to ENSO: decreasing during E1 Nifio years and increasing during La Nina years. Amplitude and phase differences between the 'real' sea level and the thermosteic sea level were substantially revealed on both seasonal and interannual time scales. As one of the possible factors, the freshwater flux might play an important role in balancing the water mass.

  19. Scientific questions about South China Sea ocean dynamics

    Institute of Scientific and Technical Information of China (English)

    HUANG Rui Xin; DU Yan

    2015-01-01

    South China Sea, its circulation and connection with other parts of the world oceans, poses important scientific questions. From the prospective view, we postulate ten key research directions to be pursued in the coming future, including ventilation of a monsoon dominated sea, water mass formation/transformation, heat/salt and water mass balance, energetics and mixing, mesoscale eddies, the role of typhoon, deep circulation and paleoclimate records, interaction with adjacent oceans, upwelling and ecology system, and response to climate changes.

  20. Bathymetric Inversion of South China Sea from Satellite Altimetry Data

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    This paper focuses on the study of ocean bathymetric inversion from satellite altimeter data by using FFT technique.In this study,the free-air gravity anomalies over the South China Sea are determined by the satellite altimeter data of GEOSAT,ERS-1,ERS-2 and T/P.And the 2.5′×2.5′ bathymetry model in South China Sea is calculated from the gravity anomalies with the inversion model given.After the analysis of the inversion and the comparison between the results,some conclusions can be drawn.

  1. Restricting factors of the development of SEA in China

    Institute of Scientific and Technical Information of China (English)

    Wang Xianghua; Zhu Xiaodong; LiYangfan; Chen Shanshan

    2006-01-01

    "Environmental Impact Assessment Law of P. R. China" was promulgated on Oct. 28th, 2002 and has been put into effect on Sep 1st, 2003. This paper puts forward some important factors which restrict the development of Strategic Environmental Assessment according to the preliminary practices of SEA in China. These restricting factors are: (1) potential resistance from some departments; (2) poor cooperation between different departments; (3) limited availability of information resources; (4) lack of well-developed SEA methods; (5) difficulties in public participation. The primary thought to solve these problems were proposed at policy and technique level.

  2. Navigating the Security Dilemma: China, Vietnam, and the South China Sea

    Directory of Open Access Journals (Sweden)

    Jason J. Blazevic

    2012-01-01

    Full Text Available Competition and conflict in the South China Sea involves many nations due to its resources and vital sea lanes. However, it is China which increasingly serves as a common denominator of intensifying anxiety for its South China Sea maritime neighbours due to the aggressive scope of its claims to the sea and its islands. Among those states, Vietnam is most affected as it is first in the path of Chinese ambitions – ambitions which authorities fear would give China significant tactical military and economic advantage. For China, there are similar fears over threats to the sea lanes and sea bed resources. Leaders of both states also perceive their diplomatic and martial actions in the sea in historical terms as well. However, enforcement actions taken by either state may lead to a worsening security dilemma in which reactive security strategies could dangerously destabilise relations. This article discusses the motivations and strategies of both states as well as the consequences of such and applies realism, its tenets of defensive and offensive realism, and neoliberalism to examine their security concerns and perceptions. The article further proposes that the most valuable insights can be provided by defensive realism and neoliberalism, which together can encourage security, cooperation and conciliation in order to best promote the improvement of relations.

  3. Inter-annual sea level variability in the southern South China Sea

    Science.gov (United States)

    Soumya, M.; Vethamony, P.; Tkalich, P.

    2015-10-01

    The South China Sea (SCS) is the largest marginal sea in the western Pacific Basin. Sea level anomalies (SLAs) in the southern South China Sea (SSCS) are assumed to be governed by various phenomena associated with the adjacent parts of the Indian Ocean and the Pacific Ocean. We have used monthly sea level anomalies obtained from 12 tide gauge stations of PSMSL and UHSLC and merged and gridded AVISO products of SLAs (sea level anomalies) derived from satellite altimeter. We find that IOD-influenced inter-annual variations are found only in the southwestern and southeastern coastal regions of SSCS. Our analysis reveals that inter-annual regional sea level drops are associated with positive phase of the IOD, and the rises with negative phase of the IOD. SLA variations at decadal scale in the southeastern and northern Gulf of Thailand correlate with Pacific Decadal Oscillations (PDO). Multiple linear regression analysis of inter-annual SLAs and climate indices shows that IOD induced inter-annual variations dominate in the southwestern SCS and it contributes to about ~ 40% of inter-annual sea level variation. Meanwhile, ENSO contributes to around ~ 30% variation in sea level in the southwestern and ~ 40% variation in the southeastern SSCS. The present study also suggests that inter-annual SLA variations in the SSCS can occur by ENSO and IOD induced changes in wind stress curl and volume transport variations.

  4. Accumulation and exploration of gas hydrate in deep-sea sediments of northern South China Sea

    Institute of Scientific and Technical Information of China (English)

    ZHANG Guangxue; CHEN Fang; YANG Shengxiong; SU Xin; SHA Zhibin; WANG Hongbin; LIANG Jinqiang; ZHOU Yang

    2012-01-01

    The large deep-sea area from the southwestern Qiongdongnan Basin to the eastern Dongsha Islands,within the continental margin of northern South China Sea,is a frontier of natural gas hydrate exploration in China.Multiform of deep-sea sedimentations have been occurred since late Miocene,and sediment waves as a potential quality reservoir of natural gas hydrate is an most important style of them.Based on abundant available data of seismic,gravity sampling and drilling core,we analyzed the characteristics of seismic reflection and sedimentation of sediment waves and the occurrence of naturat gas hydrate hosted in it,and discussed the control factors on natural gas hydrate accumulation.The former findings revealed the deep sea of the northern South China Sea have superior geological conditions on natural gas hydrate accumulation.Therefore,it will be of great significance in deep-sea natural gas hydrate exploration with the study on the relationship between deep-sea sedimentation and natural gas hydrate accumulation.

  5. The complexity of South China Sea kinematics

    Science.gov (United States)

    Sibuet, Jean-Claude; Gao, Jinyao; Zhao, Minghui; Wu, Jonny; Ding, Weiwei; Yeh, Yi-Ching; Lee, Chao-Shing

    2016-04-01

    Magnetic modeling shows that the age of the youngest South China Sea (SCS) oceanic crust is controversial (e.g. 15.5 Ma, Briais et al., JGR 1993 and 20.5 Ma, Barckhausen et al., MPG 2014). Close to the rift axis of the East sub-basin, Ar-Ar age dating of oceanic crustal rocks collected during IODP Leg 349 gives ages of 15 and 15.2 +/- 0.2 Ma (Koppers, Fall AGU meeting, 2014), which seems to favor the 15.5 Ma age given by Briais et al. modeling. However, basaltic samples might belong to a sill and not to the typical oceanic crust. As post-spreading magmatic activity (~8-13 Ma) largely masks the spreading fabric, in particular near the previously identified E-W portion of the extinct ridge axis of the East sub-basin, the published locations of the axial magnetic anomaly and spreading rates are incorrect. The compilation of available swath bathymetric data shows that if post-spreading volcanics hide the seafloor spreading magnetic fabric mostly along and near the extinct spreading axis, the whole SCS is globally characterized by rift directions following three directions: N055°in the youngest portion of the SCS, N065° and N085° in the oldest portions of the SCS (Sibuet et al., Tectonophysics 2016) suggesting the extinct ridge axis is N055° trending instead of E-W. We present an updated version of the whole SCS structural sketch based on previously published swath bathymetric trends and new detailed magnetic lineations trends compiled from an extremely dense set of magnetic data. The new structural sketch shows: - The distribution of conjugate kinematic domains, - The early opening of the NW and East sub-basins, before a jump of the rift axis, - A second ridge jump in the East basin, - The different expressions of the post-spreading magmatism in the East and SW sub-basins. In the East sub-basin, crustal magmatic intrusions led to the formation of extrusive basalts associated with the presence of numerous volcanoes (Wang et al., Geological Journal 2016). In the SW

  6. Deepwater oil and gas field development in South China Sea

    Institute of Scientific and Technical Information of China (English)

    Zhang Dagang; Wybro Pieter; Kang Yongtian

    2013-01-01

    This paper focuses on potential development models of future oil and gas exploration in South China Sea.A detailed study of current development models worldwide is performed through some examples of industry installed/ongoing projects and major technical issues encountered during these practice.Key technologies are discussed for the success of field development.Some of the technologies and field development experience can be used for South China Sea project.Several models are studied in field development for different scenarios,including marginal field,large oil field and gas field.With the massive investment activities,continued improved technologies,and rapidly growing pool of professionals,the offshore industry in China will soon encounter a golden period.

  7. A study of long-term sea level variability in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    XU Ying; LIN Mingsen; ZHENG Quanan; YE Xiaomin; LI Junyi; ZHU Benlu

    2015-01-01

    From the analyses of the satellite altimeter Maps of Sea Level Anomaly (MSLA) data, tidal gauge sea level data and historical sea level data, this paper investigates the long-term sea level variability in the East China Sea (ECS). Based on the correlation analysis, we calculate the correlation coefficient between tidal gauge and the closest MSLA grid point, then generate the map of correlation coefficient of the entire ECS. The results show that the satellite altimeter MSLA data is effective to observe coastal sea level variability. An important finding is that from map of correlation coefficient we can identify the Kuroshio. The existence of Kuroshio decreases the correlation between coastal and the Pacific sea level. Kurishio likes a barrier or a wall, which blocks the effect of the Pacific and the global change. Moreover, coastal sea level in the ECS is mainly associated with local systems rather than global change. In order to calculate the long-term sea level variability trend, the empirical mode decomposition (EMD) method is applied to derive the trend on each MSLA grid point in the entire ECS. According to the 2-D distribution of the trend and rising rate, the sea level on the right side of the axis of Kuroshio rise faster than in its left side. This result supports the barrier effect of Kuroshio in the ECS. For the entire ECS, the average sea level rose 45.0 mm between 1993 and 2010, with a rising rate of (2.5±0.4) mm/a which is slower than global average. The relatively slower sea level rising rate further proves that sea level rise in the ECS has less response to global change due to its own local system effect.

  8. Mercury Export from Mainland China to Adjacent Seas and Its Influence on the Marine Mercury Balance.

    Science.gov (United States)

    Liu, Maodian; Chen, Long; Wang, Xuejun; Zhang, Wei; Tong, Yindong; Ou, Langbo; Xie, Han; Shen, Huizhong; Ye, Xuejie; Deng, Chunyan; Wang, Huanhuan

    2016-06-21

    Exports from mainland China are a significant source of mercury (Hg) in the adjacent seas (Bohai Sea, Yellow Sea, East China Sea, and South China Sea) near China. A total of 240 ± 23 Mg was contributed in 2012 (30% from natural sources and 70% from anthropogenic sources), including Hg from rivers, industrial wastewater, domestic sewage, groundwater, nonpoint sources, and coastal erosion. Among the various sources, the Hg from rivers amounts to 160 ± 21 Mg and plays a dominant role. The Hg that is exported from mainland China increased from 1984 to 2013; the contributions from rivers, industrial wastewater, domestic sewage and groundwater increased, and the contributions from nonpoint sources and coastal erosion remained stable. A box model is constructed to simulate the mass balance of Hg in these seas and quantify the sources, sinks and Hg biogeochemical cycle in the seas. In total, 160 Mg of Hg was transported to the Pacific Ocean and other oceans from these seas through oceanic currents in 2012, which could have negative impacts on the marine ecosystem. A prediction of the changes in Hg exportation through 2030 shows that the impacts of terrestrial export might worsen without effective pollution reduction measures and that the Hg load in these seas will increase, especially in the seawater of the Bohai Sea, Yellow Sea, and East China Sea and in the sea margin sediments of the Bohai Sea and East China Sea. PMID:27243109

  9. Future acidification of marginal seas: A comparative study of the Japan/East Sea and the South China Sea

    Science.gov (United States)

    Luo, Yiming; Boudreau, Bernard P.

    2016-06-01

    The response of marginal (peripheral) seas to ocean acidification on short and long time scales is not well established. Through modeling, we examine the future acidification of two adjacent marginal seas, the South China Sea (SCS) and the Japan/East Sea (J/ES). Our results illustrate the importance of unique features in determining their acidification. The J/ES basin will become completely undersaturated with regard to calcite rapidly in the next few decades, while the SCS basin will experience relatively slower acidification. During its acidification, the J/ES will continually act as a sink for atmospheric CO2, whereas the SCS will temporarily switch from a source to a sink during the peak pCO2 interval, only to return slowly to being a source again. Marginal sea acidification will be determined by multiple factors, including their connections with the open ocean and their unique physical and biogeochemical dynamics, in addition to the level of atmospheric CO2.

  10. Mass-balance ecosystem model of the East China Sea

    Institute of Scientific and Technical Information of China (English)

    Jiahua Cheng; William W.L. Cheung; Tony J. Pitcher

    2009-01-01

    Using the Ecopath mass-balance trophodynamic model, this paper analyzed the trophic levels, flows, food web structure and ecosys-tem maturity of the East China Sea, and identified ecologically important functional groups in the ecosystem. The model is based on fishery resource surveys of the East China Sea in 2000, studies on diet composition and global databases such as FishBase and the Sea Around Us Project Database. The results showed that trophic levels of the functional groups are between 2.86 and 4.37, with an average of 3.32. Anchocy (Engraulis japonicus), small fishes and benthic crustaceans such as shrimps and crabs are important groups in terms of the trophic structure and flow dynamics in the East China Sea. Energy flows of most groups are between specific trophic levels, except file fish (Thamnaconus spp.), pomfret (Pampus spp.) and cephalopods. Trophic transfer efficiency of levels Ⅱ,Ⅲ,Ⅳ and more than Ⅴ are 11.8%, 21.1%, 17.4% and 22.1-22.5%, respectively. Effects of fishery-the largest 'consumer' of the ecosystem -are much stronger than those exerted by biological groups in the system. The model suggests that the current fishery can further reduce the complexity of the ecosystem. Evaluations of the system indices suggest that maturity of the ecosystem is low. The conclusion of this model indicates that it was the overfishing that caused the ecosystem of the East China Sea declined, which should be taken into account as a critical reference for fisheries management in the future.

  11. Distribution of drifting seaweeds in eastern East China Sea

    Science.gov (United States)

    Komatsu, Teruhisa; Tatsukawa, Kenichi; Filippi, Jean B.; Sagawa, Tatsuyuki; Matsunaga, Daisuke; Mikami, Atsuko; Ishida, Kenichi; Ajisaka, Tetsuro; Tanaka, Katsuhiko; Aoki, Masakazu; Wang, Wei-Ding; Liu, Hui-Fei; Zhang, Shou-Du; Zhou, Min-Dong; Sugimoto, Takashige

    2007-09-01

    In offshore waters with relatively low primary production, drifting seaweeds composed of Sargassum species form an identical ecosystem such as an oasis in desert. Commercially important pelagic fishes such as jack mackerel ( Trachurus japonicus) and yellow tail ( Seriola quinqueradiata) spawn in East China Sea pass their juvenile period accompanying drifting seaweeds. Therefore drifting seaweeds are very important not only in offshore ecosystem but also fishery resources. However the distribution of drifting seaweeds in East China Sea has scarcely known. Then we conducted two research cruises of R/V Hakuho-Maru in May 2002 and in March 2004. During the cruises, drifting seaweeds were visually observed from the bridge and sampled with a towing net. The observation revealed that the drifting seaweeds were distributed along the front between the Kuroshio Current and coastal waters and mainly composed of one seaweed species, Sargassum horneri (Turner) C. Agardh from spring to early summer. There are no reports on geographical distribution of this species in the coasts south of southern Kyushu Island in Japan. Kuroshio Current flows northeastward there. Buoys with GPS attached to drifting seaweeds released off Zhejiang Province, China, in March 2005 to track their transport. Their positions monitored by ORBCOM satellite showed that they were transported to the area in East China Sea, where the drifting seaweeds were observed during the cruises, in 2 months. These facts suggest that S. horneri detached from Chinese coast in March or months earlier than March could be transported to fringe area of continental shelf and waters influenced by Kuroshio Current from March to May. Therefore the Sargassum forests, especially S. horneri, along the Chinese coast play a very important role in the ecosystem of the East China Sea as a source of drifting seaweeds.

  12. Reduced inorganic sulfur in the sediments of the Yellow Sea and East China Sea

    Institute of Scientific and Technical Information of China (English)

    KANG Xuming; LIU Sumei; ZHANG Guoling

    2014-01-01

    Cold diffusion methods are used to separate and quantify the three reduced inorganic sulfur species into acid volatile sulfide (AVS), pyrite-S and element sulfur (ES) in the sediments of the Yellow and East China Seas. The results show that up to 25.02μmol/g of AVS, 113.1μmol/g of pyrite-S and 44.4μmol/g of ES are observed in the sediments of the Yellow Sea and East China Sea. Pyrite-S is the predominant sulfide mineral in the sediments, while the concentration of AVS is quite low at most stations in the study area. The amounts and reactivity of organic matter are the primary limited factor for the sulfide formation, while an iron limi-tation and a sulfate limitation are not observed in the sediments of the Yellow Sea and East China Sea. The irregular profiles of the three reduced inorganic sulfur species also reflected the comprehensive influence of sediment composition and sedimentation rates.

  13. Causes of seasonal sea level anomalies in the coastal region of the East China Sea

    Institute of Scientific and Technical Information of China (English)

    WANG Hui; LIU Kexiu; QI Dongmei; GAO Zhigang; FAN Wenjing; ZHANG Zengjian; WANG Guosong

    2016-01-01

    Based on the analysis of sea level, air temperature, sea surface temperature (SST), air pressure and wind data during 1980-2013, the causes of seasonal sea level anomalies in the coastal region of the East China Sea (ECS) are investigated. The research results show: (1) sea level along the coastal region of the ECS takes on strong seasonal variation. The annual range is 30-45 cm, larger in the north than in the south. From north to south, the phase of sea level changes from 140° to 231°, with a difference of nearly 3 months. (2) Monthly mean sea level (MSL) anomalies often occur from August to next February along the coast region of the ECS. The number of sea level anomalies is at most from January to February and from August to October, showing a growing trend in recent years. (3) Anomalous wind field is an important factor to affect the sea level variation in the coastal region of the ECS. Monthly MSL anomaly is closely related to wind field anomaly and air pressure field anomaly. Wind-driven current is essentially consistent with sea surface height. In August 2012, the sea surface heights at the coastal stations driven by wind field have contributed 50%-80% of MSL anomalies. (4) The annual variations for sea level, SST and air temperature along the coastal region of the ECS are mainly caused by solar radiation with a period of 12 months. But the correlation coefficients of sea level anomalies with SST anomalies and air temperature anomalies are all less than 0.1. (5) Seasonal sea level variations contain the long-term trends and all kinds of periodic changes. Sea level oscillations vary in different seasons in the coastal region of the ECS. In winter and spring, the oscillation of 4-7 a related to El Ni?o is stronger and its amplitude exceeds 2 cm. In summer and autumn, the oscillations of 2-3 a and quasi 9 a are most significant, and their amplitudes also exceed 2 cm. The height of sea level is lifted up when the different oscillations superposed. On the

  14. Tertiary Sea Level Changes and Sequence Stratigraphic Framework in East China Sea Shelf Basin

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The East China Sea shelf basin is a key area for setting up the sea level changes of Cenozoic in the West Pacific. Based upon the characteristics of seismic reflection, the analysis of sequence stratigraphy and depositional system, the high-resolution chronostratigraphic framework has been set up by using the data of micropaleontologic biozone fossils. The relative sea level change curve has been set up by combining analysis of paleoecology, genetic facies, specific sedimentary structures and on-lap recognized from the seismic profiles with study of geochemical characteristics. There are 4 2nd-order basin cycles showing the long-term sea level changes, and 22 3rd-order cycles showing short-term ones with relative changing ranges of 0-150 m. Transgression and regression showing long-term sea level changes bear asymmetric feature, which indicates that the speed of transgression is faster than that of regression. There are a lot of differences when compared with Haq's curve. The sequence stratigraphic framework has also been set up and 3 tectonic sequences, 7 supersequences and 19 sequences have been subdivided for Tertiary in the East China Sea shelf basin. On the basis of detailed analysis of genetic facies and log facies, 9 sedimentary systems, 20 depositional assemblages and many genetic facies have also been recognized and investigated. Based on the studies mentioned above, the favorable source and reservoir facies of gas and petroleum are indicated.

  15. Long-term Variability of Sea Surface Temperature in the East China Sea: A Review

    Directory of Open Access Journals (Sweden)

    Jae Hak Lee

    2013-06-01

    Full Text Available The long-term variability of sea surface temperature in the East China Sea was reviewed based mainly on published literatures. Though the quantitative results are not the same, it is generally shown that sea surface temperature is increasing especially in recent years with the rate of increase about 0.03oC/year. Other meaningful results presented in the literatures is that the difference of water properties between layers upper and lower than the thermocline in summer shows an increasing trend both in temperature and salinity, suggesting that the stratification has been intensified. As a mechanism by which to evaluate the wintertime warming trend in the region, the weakening of wind strength, which is related to the variation of sea level pressure and atmospheric circulation in the western North Pacific and northern Asian continent, is suggested in the most of related studies.

  16. Heavy metals in sea cucumber juveniles from coastal areas of Bohai and Yellow seas, north China.

    Science.gov (United States)

    Jiang, Haifeng; Tang, Shizhan; Qin, Dongli; Chen, Zhongxiang; Wang, Jinlong; Bai, Shuyan; Mou, Zhenbo

    2015-05-01

    The study was undertaken to assess the contents of heavy metals (Cu, Zn, Cr, Pb, Cd, As and Hg) in sea cucumber (Apostichopus japonicus) juveniles from coastal areas of Bohai and Yellow seas in northern China. Sea cucumber juveniles were collected from twenty commercial hatcheries distributed in five coastal cities. The mean concentrations obtained for heavy metals in mg/kg were as follows: Cu (0.179), Zn (2.634), Cr (0.108), Pb (0.065), Cd (0.161), As (0.372), Hg (0.034). All the mean concentrations were below the maximum residual limits set by Chinese legislation, but As in 10 % samples exceeded the safety threshold. Significant differences in contents of Cr, Pb and Hg were found among the five investigated areas. Overall, the heavy metal levels in sea cucumber juveniles were relatively low and more attention should be paid to toxic metals Pb, Cd, As and Hg in future routine monitoring program.

  17. Climate analysis of evaporation ducts in the South China Sea

    OpenAIRE

    McKeon, Brian D.

    2013-01-01

    Approved for public release; distribution is unlimited. Evaporation ducts have important implications for U.S. Naval activities involving electromagnetic propagation. The presence of an evaporation duct can affect naval operations involving communications, surveillance, electronic warfare, and detection of low-flying missiles, surface ships, or submarine periscopes. We conducted a climate scale analysis of evaporation duct heights (EDH) in the northern South China Sea (SCS), including how ...

  18. Progress of marine biodiversity studies in China seas

    OpenAIRE

    Ruiyu Liu

    2011-01-01

    Efforts have been made by scientists studying on the taxonomy, biogeography and biodiversity in China seas since 1950, the establishment of Qingdao Marine Biological Laboratory, Chinese Academy of Sciences (CAS). Over 1,000 papers and 200 volumes of monographs have been published, of which more than 47 volumes are Fauna Sinica ― Invertebrata (27 volumes on marine biota), 11 volumes of Fauna Sinica ― Vertebrata are on fishes, and 8 volumes are Flora Algarum Marinarum Sinicarum. Results of stud...

  19. Heat exchange at air-sea interface in the South China Sea during monsoon periods in 1986

    Institute of Scientific and Technical Information of China (English)

    WU Disheng; LU Boming; FENG Weizhong; XU Jianping; YAN Jinghua; ZHAO Xue; ZHOU Shuihua; ZHANG Jiwei; QIAO Guanyu; LIN Fu

    2006-01-01

    In order to explore the interaction between the sea and monsoon in the South China Sea, the heat exchanges at air-sea interface during monsoon periods in 1986 were calculated using observational data. It shows that when the summer monsoon bursts and prevails over the South China Sea, the air-sea interface heat exchange is strong and the latent heat rises rapidly in the intertropical convergence zone and the tropic cyclone system near 20.49°N, 114.14°E. On May 24, 1986, the sensible heat became positive in the typhoon system. The heating exchange indicates that heat is transported from ocean to atmosphere, with major contribution of latent heat. When the summer monsoon prevails over the South China Sea and the weather is fine, even SST (sea surface temperature) is high, but sensible heat appears to be negative. The heat exchange indicates that heat is transported from atmosphere to ocean, with major contribution of short-wave radiation absorbed by sea surface and sensible heat. When summer monsoon is over and the northeast monsoon prevails over the South China Sea, the heat exchange at air-sea interface is very strong. The heating exchange shows that the ocean heats the atmosphere, with major contribution of latent heat when cold air arrives at the sea surface and the sensible heat rises to positive rapidly. Therefore it can be concluded that the heat exchange at air-sea interface is different from the SST in South China Sea. When the summer monsoon prevails over the South China Sea, the main trend is the ocean responding to the atmosphere.

  20. Chemical hydrography of coastal upwelling in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    WANG Baodong; WANG Xiulin

    2007-01-01

    Based on the field data obtained during cruises on the shelf of the East China Sea from 1997 to 1999, seasonal variations of coastal upwelling on the inner shelf are discussed by using cross-shelf transect profiles and horizontal distributions of chemical and hydrographic variables. Results show that the coastal upwelling was year-round, but the areas and intensities of the upwelling were quite different in season. The coastal upwelling occurred in all of the coastal areas of the region in spring and summer, but in autumn only in the area off Zhejiang Province, and in winter in the area off Fujian Province. It was the strongest in summer and the weakest in winter. Geographically, it was the strongest in the area off Zhejiang Province and the weakest in the southmost or northmost parts of the East China Sea.The estimated nutrient fluxes upward into euphotic zone through coastal upwelling were quite large, especially for phosphate, which contributed significantly to primary production and improved the nutrient structure of the coastal ecosystem in the East China Sea.

  1. Modal Wave Number Tomography for South China Sea Front

    Institute of Scientific and Technical Information of China (English)

    彭临慧; 王宁; 邱晓芳; 田纪伟

    2003-01-01

    Monitoring of the South China Sea is always one of the focuses in the field of ocean engineering for its particular geographic position. The modal wave number tomography is proposed for monitoring the front and numerical simulation is performed for the front of the South China Sea. With the empirical orthonormal function (EOF) applied to reduce the parameter search space, the perturbation inversion method is used for inversing sound speed profiles. The 2-D ocean environment used for numerical simulation is selected from the ocean area, located in 20°N, 118°E~20°N, 125°E, near the Luzon Strait in the South China Sea. The ocean environment sound speed distribution in the ocean area under study is obtained from the assimilation of multi-source remote sensing data. The numerical simulation shows that the modal wave number tomography can inverse the average sound speed profile, therefore,it can be used to monitor ocean internal structures such as ocean fronts and eddies which affect sound speed distribution.

  2. Mitochondrial DNA variation in the East China Sea and Yellow Sea populations of swimming crab Ovalipes punctatus.

    Science.gov (United States)

    Zheng, Wei; Han, Zhiqiang; Chen, Guobao; Yu, Cungen; Gao, Tianxiang

    2015-08-01

    Swimming crab Ovalipes punctatus is a commercially important species in the East China Sea and Yellow Sea, but there is limited knowledge of its genetic population structure. The population genetic structure of O. punctatus in East China Sea and Yellow Sea was examined with a 658-bp segment of the mtDNA COI gene. A total of 60 individuals were collected from five locations and 48 haplotypes were obtained. Mean haplotype diversity and nucleotide diversity for the five populations were 0.9876 ± 0.0068 and 0.0074 ± 0.0041, respectively. Analysis of molecular variance (AMOVA) detected no significant differences at all hierarchical levels, and all FST values were non-significant, indicating that no significant population genetic structure exists in the East China Sea and Yellow Sea. These results supported the null hypothesis that O. punctatus within the East China Sea and Yellow Sea constitutes a panmictic mtDNA gene pool. Neutrality tests and mismatch distribution supported population expansion in this species, indicating that climate change could play an important role in affecting the demographic history of marine species. Strong dispersal capacity of larvae and adults, and ocean currents in the studied area could be the reasons for genetic homogeneity in this species in the East China Sea and Yellow Sea. Another explanation for the lack of phylogeographic structure in O. punctatus might reflect a recent range expansion after the last glacial maximum and insufficient time to attain migration-drift equilibrium.

  3. Relationship between Antarctic sea ice and the climate in summer of China

    Institute of Scientific and Technical Information of China (English)

    Ma Lijuan; Lu Longhua; Bian Lingen

    2006-01-01

    The variations of sea ice are different in different regions in Antarctica,thus have different impacts on local atmospheric circulation and global climatic system. The relationships between the sea ice in Ross Sea and Weddell Sea regions and the synoptic climate in summer of China are investigated in this paper via diagnostic analysis methods by using global sea ice concentration gridded data covering Jan. 1968through Dec. 2002 obtained from Hadley Center, combined with Geopotential Height on 500hPa and 100hPa over North Hemisphere and monthly precipitation and air temperatures data covering the corresponding period over 160 meteorological stations in China obtained from CMA (China Meteorological Administration). Results disclose that both these two regions are of indicative meanings to the climate in summer of China. The Ross Sea Region is the key sea ice region to the precipitation in Northeast China in summer. More sea ice in this region in September will result in less precipitation in Northeast China in the following June. Weddell Sea Region is the key sea ice region to the air temperature in Northeast China in summer. More sea ice in this region in September will contribute to lower air temperature in Northeast China in the following June.

  4. Distributions and sources of volatile chlorocarbons and bromocarbons in the Yellow Sea and East China Sea

    International Nuclear Information System (INIS)

    Highlights: • Concentrations of the six VHOC were determined in the Yellow Sea and East China Sea. • VHOC distributions were affected by anthropogenic, biologic and hydrographic factors. • Diurnal variations of the six VHOC were observed. • Relationships between VHOC and related parameters were discussed. • Sources of the six VHOC were identified by principal component analysis. - Abstract: Six volatile halogenated organic compounds (VHOC), namely, chloroform, carbon tetrachloride, trichloroethylene, bromodichloromethane, dibromochloromethane, and bromoform, were studied in the Yellow Sea and East China Sea from April to May, 2009. The spatial variability of these VHOC was influenced by various factors, including anthropogenic inputs, biogenic production and complicated hydrographic features such as Changjiang Diluted Water, Yellow Sea Cold Water Mass, and Kuroshio Current. Diurnal study results showed that factors such as solar irradiation, biological activity, and tide affected the abundance of these VHOC. Correlation analyses revealed that bromodichloromethane was positively correlated with chlorophyll a in surface seawater. Principal component analysis suggested that chlorinated compounds like carbon tetrachloride originated from anthropogenic sources whereas brominated compounds such as bromodichloromethane originated from biogenic sources. Sources of other chlorinated and brominated compounds may not be governed by biological processes in the marine environment

  5. Modern sedimentation and extreme event in the South China Sea

    Science.gov (United States)

    Chen, Yu-Huang; Su, Chih-Chieh

    2016-04-01

    The South China Sea is the largest marginal sea of the northwest Pacific. It is situated at the plate boundary of the Eurasian, Philippine Sea, and Indian plates and also on the North Western Pacific corridor of typhoons. The unique tectonic and climatic environment makes it has to face the potential of seafloor destructions, like submarine landslides and slumps, and high sediment discharges which induced by typhoon from Philippine. In this study, we analysis the sediment properties of modern extreme event records in cores and attempt to evaluate the history of extreme events in the South China Sea. Twelve gravity cores were collected in the central South China Sea basin and around Taiping island by using R/V Ocean Research 1 from 2014 to 2015 and a series of analysis including multi-sensor core logger, XRF core scanner (Itrax), core surface images, X-radiographs, bulk density, grain size, Pb-210 chronology and X-ray diffractometer were conducted in this study. On core surface images, an obvious brownish oxidized layer exist in core top with higher Pb-210 activity beneath this oxidized layer, and we speculate this layer is caused by nature hazard. According to the sampling time, we conjecture the oxidized layer might formed by typhoon Haiyan in 2013. In addition, the Itrax data shows high manganese content only exist in this layer which might related to the modern industrial pollution delivered by typhoon induced flooding from Philippine. The sedimentation rate of the non-event years in these cores which derived from Pb-210 chronology method is about 0.02 ~0.03 cm/yr. On contrary, the event layer caused by Haiyan with a recorded maximum 87cm deposits in the South China Sea. This study aims to characterize the typhoon induced deposits in the turbidite layer and use it to identify whether the other event layers recorded in these cores were related to typhoon activities and to reconstruct the strong tropical cyclone history in the western Pacific.

  6. Mean sea surface heights of the South and East China Seas from ocean circulation model and geodetic leveling

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The mean sea surface heights (sea surface topography) of the South China, East China, Yellow and Bohai Seas are derived from an ocean general circulation model and surface air pressure. The circulation model covers the global oceans, with fine grid (1/6°) covering the East Asian marginal seas and coarse grid (3°) covering the rest part of the global oceans. The result shows that the China 1985 National Altitude Datum is 24.7 cm above the mean sea surface height of the world oceans. The mean sea surface in the coastal ocean adjacent to China is higher in the south than in the north. Intercomparison of the model results with the geodetic leveling measurements at 28 coastal tidal stations shows a standard deviation of 4.8 cm and a fitting coefficient of 95.3%. After correction through linear regression, the standard deviation is reduced to 4.5 cm. This indicates that the accuracy of rmodel results is sufficient for practical application. Based on the model results, the mean sea surface heights for the study area with a resolution of 1/6 degree are given. This result also links the mean sea levels at islands with those on the mainland coast and gives the mean sea surface heights at tidal stations in the Taiwan Island, the Dongsha Islands, the Xisha Islands and the Nansha Islands relative to the China 1985 National Altitude Datum.

  7. Effect of Sea Level Variation on Tidal Characteristic Values for the East China Sea

    Institute of Scientific and Technical Information of China (English)

    于宜法; 俞聿修; 左军成; 万振文; 陈宗镛

    2003-01-01

    Tidal waves in the East China Sea are simulated numerically with POM(Princeton Ocean Model) model for normal mean sea level, 30 cm higher, 60 cm higher, and 100 cm higher, respectively, and the simulated result is compared with the harmonic analysis result of hourly sea level data from 19 tide gauges for more than 19 years. It is indicated that the long-term mean sea level variation affects notably tidal waves in this region. Generally, the tidal amplitude increases when the mean sea level rises, but this relationship may be inverse for some sea areas. The maximal variation of tidal amplitude takes place in the zones near the Fujian coast and the Zhejiang coast, rather than the shallowest Bohai Sea. The maximum increase of M2 amplitude can exceed about 15 cm corresponding to the 60 cm rise of the mean sea level along the Fujian coast. The other regions with large variations of tidal amplitude are those along the Jiangsu coast, the south-east coast of Shandong, and the south-east coast of Dalian. The propagation of tidal waves is also related to mean sea level variation, and the tidal phase-lag decreases generally when the mean sea level rises. Almost all the regions where the tidal phase-lag increases with rising mean sea level are close to amphidromic points, meanwhile the spatial area of such regions is very small. Because the influence of mean sea level variation upon tidal waves is spatially marked, such spatial effect should be considered in calculation of the tidal characteristic value and engineering water level. In the region where the amplitudes of the major tidal constituents increase, the probable maximum high water level becomes higher, the probable maximum low water level becomes lower, and both design water level andcheck water level increase obviously. For example, the design water level at Xiamen increases by 13.5 cm due to the variation of tidal waves when the mean sea level rises 60 cm, the total increase of design water level being 73.5 cm.

  8. Chinese assertiveness in the South China Sea and Southeast Asian responses

    OpenAIRE

    Thayer, Carlyle A.

    2011-01-01

    This article reviews Chinese assertive behaviour towards the Philippines and Vietnam over South China Sea issues in 2011. The article compares and contrasts Chinese diplomatic behaviour in the period before and after the adoption by ASEAN member states and China of Guidelines for the Implementation the Declaration on Conduct of Parties in the South China Sea in July. In the first period China aggressively asserted its claims to sovereignty by interfering with commercial fishing and oil explor...

  9. The South China sea margins: Implications for rifting contrasts

    Science.gov (United States)

    Hayes, D.E.; Nissen, S.S.

    2005-01-01

    Implications regarding spatially complex continental rifting, crustal extension, and the subsequent evolution to seafloor spreading are re-examined for the northern and southern-rifted margins of the South China Sea. Previous seismic studies have shown dramatic differences in the present-day crustal thicknesses as the manifestations of the strain experienced during the rifting of the margin of south China. Although the total crustal extension is presumed to be the same along the margin and adjacent ocean basin, the amount of continental crustal extension that occurred is much less along the east and central segments of the margin than along the western segment. This difference was accommodated by the early formation of oceanic crust (creating the present-day South China Sea basin) adjacent to the eastern margin segment while continued extension of continental crust was sustained to the west. Using the observed cross-sectional areas of extended continental crust derived from deep penetration seismics, two end-member models of varying rift zone widths and varying initial crustal thicknesses are qualitatively examined for three transects. Each model implies a time difference in the initiation of seafloor spreading inferred for different segments along the margin. The two models examined predict that the oceanic crust of the South China Sea basin toward the west did not begin forming until sometime between 6-12 my after its initial formation (???32 Ma) toward the east. These results are compatible with crustal age interpretations of marine magnetic anomalies. Assuming rifting symmetry with conjugate margin segments now residing along the southern portions of the South China Sea basin implies that the total width of the zone of rifting in the west was greater than in the east by about a factor of two. We suggest the most likely causes of the rifting differences were east-west variations in the rheology of the pre-rift crust and associated east-west variations in the

  10. Pigment signatures of some diatoms isolated from China seas

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The photosynthetic pigments of 12 species (14 strains) of cultured diatoms from six genera under specific conditions were examined by the HPLC. The diatom genera were Skeletonema, Thalassiosira, Chaetoceros, Nitzschia, Phaeodactylum and Meuniera. All strains were isolated from China seas and most of them were from the Jiaozhou Bay, China. Fifteen pigments were identified and eight of them were various chlorophyll a derivatives. Chlorophyll a, c2 and c1 and the carotenoids fucoxanthin, diadinoxanthin, diatoxanthin and β,β-carotene existed in all species. The ratios of each pigment to chlorophyll a were compared with the results in literatures. The pigment ratios of this study generally fall within the ranges reported by the literatures although the maximum ratio of fucoxanthin to chlorophyll a was higher and the ratios of chlorophyll c and diatoxanthin to chlorophyll a were low. The pigment ratios are useful to understanding the pigment signatures of diatoms in the Jiaozhou Bay, China, and to setting up the chemotaxonomic method ofphytoplankton in these sea areas.

  11. Numerical Study of Water and Suspended Matter Exchange Between the Yellow Sea and the East China Sea

    Institute of Scientific and Technical Information of China (English)

    庞重光; 白学志; 胡敦欣

    2003-01-01

    POM was used to study the monthly mean circulation in the Yellow Sea and East China Sea. The calculated results showed almost all major characteristics of the circulation system. The calculated circulation system and observational data were used to determine the sediment concentration, volume transport, heat flux and suspended matter flux between the Yellow Sea and the East China Sea. The conclusions obtained were that the volume and heat are transported northward through the 32°N section during each season; that in winter and autumn, total suspended matter is transported southward, and is larger in winter than in autumn. The reason is that the Yellow Sea Coastal Current is strong and always contains more suspend matter in winter and autumn. The seasonal suspended matter exchange between the Yellow Sea and the East China Sea are 0.58 x 107 tons in spring, 2.81 x 107 tons in summer, - 2.60 x 107 tons in autumn and - 3.40 x 107 tons in winter. Net flux of suspended matter from the Yellow Sea to the East China Sea is 2.61 x 107 tons every year.

  12. Distribution characteristics of zooplankton biomass in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    XU Zhaoli; CHAO Min; CHEN Yaqu

    2004-01-01

    On the basis of the data of oceanographic survey in the East China Sea in four seasons during 1997~2000 (23°30′~33°00′N,118°30′~ 128°E), the variation of total biomass and diet biomass of zooplankton and their spatial-temporal distribution and relationship with the fishing ground of Engraulisjaponicus are approached and analyzed. The results show that the average biomass is 65.32 mg/m3 in four seasons, autumn (86.18 mg/m3) being greater than summer (69.18 mg/m3) greater than s pring ( 55.67 mg/m3) greater than winter (50.33 mg/m3). The average value of diet zooplankton biomass is 40.9 mg/m3.The trends of horizontal distribution both in the total biomass and the diet biomass of zooplankton are similar. The high biomass region (250~500 mg/m3) is very limited, only accounting for 1% of the investigation area. Seasonal variation of the biomass is very remarkable in the west and north parts of East China Sea coastal waters ( 29°30′N, 125°E). The horizontal distribution of diet zooplankton depends on the abundance distribution of crustacean. The distribution of diet zooplankton is related to the fishing ground of Engraulis japonicus and the high-density area of young fish and larval. In spring, the central fishing ground of Engraulis japonicus (>100 kg/h) and the high-density area of young fish and larval (>100 individuals per net) are located at the same place of high-density (100~250 mg/m3)area of diet zooplankton in the middle-southern part of East China Sea or the edge of its waters.

  13. Distribution characteristics of zooplankton biomass in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    XU Zhaoli; CHAO Min; CHEN Yaqu

    2004-01-01

    On the basis of the data of oceanographic survey in the East China Sea in four seasons during 1997~2000 (23°30′~33°00′N,118°30′~ 128°E), the variation of total biomass and diet biomass of zooplankton and their spatial-temporal distribution and relationship with the fishing ground of Engraulis japonicus are approached and analyzed. The results show that the average biomass is 65.32 mg/m3 in four seasons, autumn (86.18 mg/m3) being greater than summer (69.18 mg/m3) greater than spring (55.67 mg/m3) greater than winter (50.33 mg/m3). The average value of diet zooplankton hiomass is 40.9 mg/m3.The trends of horizontal distribution both in the total biomass and the diet biomass of zooplankton are similar. The high biomass region (250~500 mg/m3) is very limited, only accounting for 1% of the investigation area. Seasonal variation of the biomass is very remarkable in the west and north parts of East China Sea coastal waters (29°30'N,125°E). The horizontal distribution of diet zooplankton depends on the abundance distribution of crustacean. The distribution of diet zooplankton is related to the fishing ground of Engraulis japonicus and the high-density area of young fish and larval. In spring, the central fishing ground of Engraulis japonicus (>100 kg/h) and the high-density area of young fish and larval (>100 individuals per net) are located at the same place of high-density (100~250 mg/m3)area of diet zooplankton in the middle-southern part of East China Sea or the edge of its waters.

  14. Seismic stratigraphy of the Qiongdongnan deep sea channel system, northwest South China Sea

    Institute of Scientific and Technical Information of China (English)

    YUAN Shengqiang; L(U) Fuliang; WU Shiguo; YAO Genshun; MA Yubo; FU Yanhui

    2009-01-01

    Based on more than 4000 km 2D seismic data and seismic stratigraphic analysis, we discussed the extent and formation mechanism of the Qiongdongnan deep sea channel. The Qiongdongnan deep sea channel is a large incised channel which extends from the east boundary of the Yinggehai Basin, through the whole Qiongdongnan and the Xisha trough, and terminates in the western part of the northwest subbasin of South China Sea. It is more than 570 km long and 4-8 km wide. The chaotic (or continuous) middle (or high) amplitude, middle (or high) continuity seismic facies of the channel reflect the different lithological distribution of the channel. The channel formed as a complex result of global sea level drop during early Piiocene, large scale of sediment supply to the Yinggehai Basin, inversion event of the Red River strike-slip fault, and tilted direction of the Qiongdongnan Basin. The large scale of sediment supply from Red River caused the shelf break of the Yinggehai Basin to move torwards the S and SE direction and developed large scale of prograding wedge from the Miocene, and the inversion of the Red River strike-slip fault induced the sediment slump which formed the Qiongdongnan deep sea channel.

  15. Sea level rise projection in the South China Sea from CMIP5 models

    Institute of Scientific and Technical Information of China (English)

    HUANG Chuanjiang; QIAO Fangli

    2015-01-01

    Future potential sea level change in the South China Sea (SCS) is estimated by using 24 CMIP5 models under different representative concentration pathway (RCP) scenarios. By the end of the 21st century (2081–2100 relative to 1986–2005), the multimodel ensemble mean dynamic sea level (DSL) is projected to rise 0.9, 1.6, and 1.1 cm under RCP2.6, RCP4.5, and RCP8.5 scenarios, respectively, resulting in a total sea level rise (SLR) of 40.9, 48.6, and 64.1 cm in the SCS. It indicates that the SCS will experience a substantial SLR over the 21st century, and the rise is only marginal larger than the global mean SLR. During the same period, the steric sea level (SSL) rise is estimated to be 6.7, 10.0, and 15.3 cm under the three scenarios, respectively, which accounts only for 16%, 21% and 24% of the total SLR in this region. The changes of the SSL in the SCS are almost out of phase with those of the DSL for the three scenarios. The central deep basin has a slightly weak DSL rise, but a strong SSL rise during the 21st century, compared with the north and southwest shelves.

  16. Dynamics of the cross-shelf circulation in the Yellow and East China Seas in winter

    Science.gov (United States)

    Yuan, Dongliang; Hsueh, Ya

    2010-10-01

    A general ocean circulation model is used to study the dynamics of the cross-shelf circulation in the Yellow and East China Seas in winter. The model results show that the shelf circulation in winter is induced primarily by the northerly monsoonal winds. Compared with the wind-driven circulation, the Kuroshio-forced circulation over the shelf is very weak. The westward shift of the Yellow Sea Warm Current is produced by the northerly winds through the generation of a sea-level trough off the Subei coasts and a sea-level ridge along the center of the Yellow Sea topographic trough. The sea-level trough off the Subei coasts is produced because the sea level at the coast is tied to the depression in the northern Yellow Sea and is moderated by the surface Ekman transport of the northerly monsoon. The sea-level ridge along the center of the Yellow Sea topographic trough is produced because the sea level along both the east China and the west Korea coasts decreases. The structure of the sea level gives rise to a geostrophic intrusion against the wind along the western side of the Yellow Sea trough and southward movement of the Korean coastal currents along the eastern side of the trough. Under the northerly wind forcing, the currents over the East China Sea shelf flow southward in an opposite direction to the Yellow Sea Warm Current. The resulting divergence, therefore, forces the Yellow Sea Coastal Current to move offshore to form the East China Sea Current. At the head of the submarine canyon off the Changjiang mouth, a northward intrusion is produced by downwind pile-up of sea level and by the wind-curl forcing. The Yellow Sea Warm Current and the canyon intrusion then extend southward through the propagation of topographic Rossby waves to reverse the wind-driven currents over the East China Sea shelf, generating the offshore and inshore branches of the Taiwan Warm Current, both of which serve to raise the sea level over the East China Sea shelf. The final adjustment

  17. Records of Toba eruptions in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    LlANG; Xirong

    2001-01-01

    [1]Rose,W. I., Chesner, C. A., Dispersal of ash in the great Toba eruption, 75 ka, Geology, 1987, 15: 913-917.[2]Acharyya, S. K., Basu, P. K. ,Toba ash on the Indian subcontinent and its implications for correlation of late Pleistocene alluvium, Quaternary Research, 1993, 40: 10-19.[3]Shane, P., Westgate, J., Williams, M. et al., New geochemical evidence for the youngest Toba Tuff in India, Quaternary Research, 1995, 44: 200-204.[4]Westgate, J. A., Sha ne, P. A. R., Pearce, N. J. G. et al., All Toba occurrences across Peninsular India belong to the 75000yr B. P. eruption, Quaternary Research, 1998, 50:107-112.[5]Pattan, J. N., Shane, P., Banakar, V. K., New occurrences of youngest Toba Tuff in abyssal sediments of the Central Indian Basin, Marine Geology, 1999, 155: 243-248.[6]Gasparotto, G., Spadafora, E,, Summa, V. et al., Contribution of grain size and compositional data from the Bengal Fan sediment to the understanding of Toba volcanic event, Marine Geology, 2000, 162: 561-572.[7]Dehn, J., Farrell, J. W., Schmincke, H. U., Neogene tephrochronology from Site 758 on northern Ninetyeast Ridge: Indon isian arc volcanism of the Past 5 Ma, Proceedings of the Ocean Drilling Program, Scientific Results (eds. Weissel, J. P.,Taylor, E., Alt, J. et al.), College Station, Texas, Ocean Drilling Program, 1991, 121: 273-295.[8]Lee M. Y., Wet, K. Y., Chen, Y. G., High-resolution oxygen isotope stratigraphy for the last 150000 years in the southern South China Sea, Terrestrial, Atmospheric and Oceanic Sciences TAO, 1999, 10: 239-254.[9]Biihring, C., Sarnthein, Toba ash layers in the South China Sea: Evidence of contrasting wind directions during eruption ca.74 ka, Geology, 2000, 28: 275-278.[10]Chesner, C. A., Petrogenesis of the Toba tuffs, Sumatra, Indonesia, Journal of Petrology, 1998, 39: 397-438.[11]Rampino, M. R., Self. S., Volcanic winter and accelerated glaciation follow ing the Toba super-eruption, Nature, 1992, 359:50-52.

  18. SEASONAL AND INTER-ANNUAL VARIABILITY OF THE SOUTH CHINA SEA WARM POOL AND ITS RELATION TO THE SOUTH CHINA SEA MONSOON ONSET

    Institute of Scientific and Technical Information of China (English)

    赵永平; 陈永利

    2001-01-01

    The South China Sea warm pool interacts vigorously with the summer monsoon which is active in the region. However, there has not been a definition concerning the former warm pool which is as specific as that for the latter. The seasonal and inter-annual variability of the South China Sea warm pool and its relations to the South China Sea monsoon onset were analyzed using Levitus and NCEP/NCAR OISST data. The results show that, the seasonal variability of the South China Sea warm pool is obvious, which is weak in winter, develops rapidly in spring, becomes strong and extensive in summer and early autumn, and quickly decays from mid-autumn. The South China Sea warm pool is 55 m in thickness in the strongest period and its axis is oriented from southwest to northeast with the main section locating along the western offshore steep slope of northern Kalimantan-Palawan Island. For the warm pools in the South China Sea, west Pacific and Indian Ocean, the oscillation, which is within the same large scale air-sea coupling system, is periodic around 5 years. There are additional oscillations of about 2.5 years and simultaneous inter-annual variations for the latter two warm pools. The intensity of the South China Sea warm pool varies by a lag of about 5 months as compared to the west Pacific one. The result also indicates that the inter-annual variation of the intensity index is closely related with the onset time of the South China Sea monsoon. When the former is persistently warmer (colder) in preceding winter and spring, the monsoon in the South China Sea usually sets in on a later (earlier) date in early summer. The relation is associated with the activity of the high pressure over the sea in early summer. An oceanic background is given for the prediction of the South China Sea summer monsoon, though the mechanism through which the warm pool and eventually the monsoon are affected remains unclear.

  19. An oil slick spectral experiment of nearshore sea water in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    WANG Difeng; PAN Delu; GONG Fang; WANG Tianyu; ZHAN Yuanzeng

    2013-01-01

    Along with the rapid advance in global industrialization, oil spill events caused by offshore operations, trans-portation and accidents are increasing. Compared with ship surveys, monitoring oil spills through remote sensing has real-time, comprehensive, low-cost advantages, which can effectively guide cleaning and evalu-ation, and reduce the marine ecological destruction resulting from oil spills. Therefore, studying the remote sensing mechanism used to monitor marine oil spills is of great significance for ecological environmen-tal protection. This paper describes an experiment and corresponding analysis based on the above-water method, using the East China Sea coastal turbid water. The analysis shows that“upward short-wave”in ultraviolet and blue-purple bands and its displacement, along with the changing thickness, are important characteristics for distinguishing between the oil slick and the sea water, and also to differentiate oil slicks of different thicknesses. From blue to near-infrared bands, the spectrum of lube oil is flatter than that of diesel, and the diesel spectrum rises faster than the lube spectrum on the right side of the trough at 400 nm. These two features form an important basis for differentiating diesel from lube oil. These analyses will further the development of oil spill remote sensing in the East China Sea.

  20. Seasonal Variability of the Yellow Sea/East China Sea Surface Fluxes and Thermohaline Structure

    Institute of Scientific and Technical Information of China (English)

    Peter CHU; CHEN Yuchun; Akira KUNINAKA

    2005-01-01

    We use the U.S. Navy's Master Oceanographic Observation Data Set (MOODS) for the Yellow Sea/East China Sea (YES) to investigate the climatological water mass features and the seasonal and non-seasonal variabilities of the thermohaline structure, and use the Comprehensive Ocean-Atmosphere Data Set (COADS) from 1945 to 1989 to investigate the linkage between the fluxes (momentum, heat, and moisture) across the air-ocean interface and the formation of the water mass features. After examining the major current systems and considering the local bathymetry and water mass properties, we divide YES into five regions: East China Sea (ECS) shelf, Yellow Sea (YS) Basin, Cheju bifurcation (CB) zone, Taiwan Warm Current (TWC) region, Kuroshio Current (KG) region. The long term mean surface heat balance corresponds to a heat loss of 30 W m-2 in the ESC and CB regions, a heat loss of 65 W m-2 in the KG and TWC regions, and a heat gain of 15 W m-2 in the YS region. The surface freshwater balance is defined by precipitation minus evaporation. The annual water loss from the surface for the five subareas ranges from 1.8 to 4 cm month-1. The fresh water loss from the surface should be compensated for from the river run-off. The entire water column of the shelf region (ECS, YS, and CB) undergoes an evident seasonal thermal cycle with maximum values of temperature during summer and maximum mixed layer depths during winter. However, only the surface waters of the TWC and KG regions exhibit a seasonal thermal cycle.We also found two different relations between surface salinity and the Yangtze River run-off, namely, out-of-phase in the East China Sea shelf and in-phase in the Yellow Sea. This may confirm an earlier study that the summer fresh water discharge from the Yangtze River forms a relatively shallow, low salinity plume-like structure extending offshore on average towards the northeast.

  1. Brief Understanding of the South China Sea Intermittent Line and China’s Relations With Its Neighbors Surrounding the South China Sea

    Institute of Scientific and Technical Information of China (English)

    Hou; Yi

    2014-01-01

    <正>I,Formation of the South China Sea"Intermittent Line"According to historical records,as early as the Qin and Han dynasties,Chinese people began sailing activities onto the Oceans.With the ongoing maritime activities,and improved shipbuilding technology and expanded fishing,the Chinese people in the Han Dynasty first discovered the islands in the South China Sea,

  2. Numerical Simulation of the Influence of Mean Sea Level Rise on Typhoon Storm Surge in the East China Sea.

    OpenAIRE

    Gao, Zhigang; Han, Shuzong; Liu, Kexiu; Zhrng, Yunxia; Yu, Huaming

    2008-01-01

    In this paper, ECOMSED (Estuarine Coastal Ocean Model with sediment transport) model is employed to simulate storm surge process caused by typhoon passing across East China Sea in nearly years. Capability of ECOMSED to simulate storm surge is validated by comparing model result with observed data. Sensitivity experiments are designed to study the influence of sea level rise on typhoon storm surge. Numerical experiment shows that influence of mean sea level rise on typhoon storm surge is non-u...

  3. Internal solitary waves in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    LI Xiaofeng; ZHAO Zhongxiang; HAN Zhen; XU Liuxiong

    2008-01-01

    A European Space Agency's ENVISAT advanced synthetic aperture radar (ASAR) image covering Zhejiang coastal water in the East China Sea (ECS) was acquired on 1 August 2007. This image shows that there are about 20 coherent internal solitary wave (ISW) packets propagating southwestward toward Zhejiang coast. These ISW packets are separated by about 10 kin, suggesting that these ISWs are tide-generated waves. Each ISW packet contains 5--15 wave crests. The wavelengths of the wave crests with-in the ISW packets are about 300 m. The lengths of the leading wave crests are about 50 km. The ISW amplitude is estimated from solving KdV equation in an ideal two-layer ocean model. It is found that the ISW amplitudes is about 8 m. Further analysis of the ASAR image and ocean stratification profiles show that the observed ISWs are depression waves. Analyzing the tidal current finds that these waves are locally generated. The wavelength and amplitude of the ECS ISW are much smaller than their counter-parts in the South China Sea (SCS). The propagation speed of the ECS ISW is also an order of magnitude smaller than that of the SCS ISW. The observed ISWs in the ECS happened during a spring tide period.

  4. Ocean primary productivity estimation of China Sea by remote sensing

    Institute of Scientific and Technical Information of China (English)

    PAN Delu; GUAN Wenjiang; BAI Yan; HUANG Haiqing

    2005-01-01

    Ocean primary productivity is a key parameter in the research of global carbon cycle, ocean biological resources, and in evaluation of the feature and quality of ocean biological environment. Traditional shipboard measurement which is costly and time-consuming is impossible to obtain the spatial and temporal information on primary productivity on a large scale in a short period of time. Satellite remote sensing is an effective strategy to acquire the ocean information in near real time. Here we propose a model special for China Sea based on the concept of primary productivity using in situ primary productivity and environmental data from 1984 to 1990, and discuss every modeling parameter which can be retrieved by remote sensing in detail. The reliability of this model is tested by in situ data, and the comparison of other primary productivity models is made. We also analyze the temporal and spatial distribution of China Sea primary productivity in 2000. From our analysis the satellite remote sensing data have been proved very useful for ocean primary productivity study.

  5. Profiler-sonobuoy measurements in the South China Sea basin

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, W.J.; Kumar, N.; Houtz, R.E.

    1979-07-10

    Analyses of single-channel seismic reflection profiles, and wide-angle reflection and refraction data from sonobuoys, indicate that the deep part of the South China Sea basin is typically oceanic in structure, except that layer 2 is about 1 km thicker than usual and layer 3 is only about half the usual thickness. The top of layer 2 has a rough upper surface and becomes deeper in the northern part of the basin, where it is overlain by sediments of velocity 1.7--3.8 km/s up to 3 km thick. A 6-km-thick sequence of sediments fills a basement depression just north of the outer subsurface (peripheral) ridge of the Sunda shelf. Thick sediments were measured at the outer parts of the Sunda shelf, Palawan shelf, Northeast Borneo shelf, and in the Taiwan straits south of the Penghu-Peikang basement high. The Manila trench is divided into two sections, a sediment-filled trench between southernmost Taiwan and Stewart bank off central northern Luzon and a topographic trench between Stewart bank southward into the Mindoro straits. Burial of part of the trench by sediments that thicken to the north and the thick sediment cover of the northern South China Sea basin indicate provenance from the north. The northern margin of the South China Sea basin is predominantly a zone of tension the southern margin is predominantly a zone of compression, the western margin may be a zone of shear, and the eastern margin is a subduction zone. It seems probable that the southern margin of the basin, called the Reed bank crustal block, was formerly attached to mainland Asia. Sometime during the Paleogene the Reed bank crustal block broke away from the continent, and new sea floor was created between the southeastward migrating block and the Asian mainland. Old ocean crust in front of the advancing block was subducted along the northwestern sides of Borneo and Palawan. Subduction ceased in the early Miocene with the collision of the crustal block and the Borneo-Palawan isthmian ridge.

  6. PRELIMINARY STUDY OF RELATIONSHIP BETWEEN INTERANNUAL VARIATIONS OF SST IN SOUTH CHINA SEA AND TROPICAL INDIAN OCEAN AND SOUTH CHINA SEA MONSOON OUTBREAK

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Conclusions are divided regarding the role of the variations of thermodynamics in the monsoon activity for the South China Sea region. In this study, primary eigenvectors are studied for the SSTA from East Asia to the tropical eastern Indian Ocean in May. The results show that temperature anomalies that center on Sumatra are closely related with the outbreak of the South China Sea monsoon. When the SST is warmer (cooler) than average year, it is likely that the monsoon set in late (early). It may be caused by the changes in meridional difference in thermodynamics between the Indochina Peninsula and its southern tropical oceans. Studying the temporal and spatial evolution of primary eigenvector distribution of the SSTA in the South China Sea-tropical eastern Indian Ocean from winter to summer, we find that the temperature anomalies that center around Sumatra in late spring and early summer can be traced back to the variations of the SST fields in the South China Sea in the preceding winter. Being well associated with the outbreak of the South China Sea monsoon, the latter is a significant index for it. The work helps understanding the atmospheric and oceanic background against which the South China Sea monsoon breaks out and behaves.

  7. Model study of the upper circulation in the Sulu Sea and its relation to the South China Sea circulation

    Institute of Scientific and Technical Information of China (English)

    CAI Shuqun; HE Yinghui; LONG Xiaomin; WANG Shengan

    2008-01-01

    According to the satellite remote sensing monthly mean sea surface temperature data from 1998 to 2002, it is shown that, the Sulu Sea is dominated by a cold eddy both in summer and winter. A coupled single-layer/two-layer model is employed here to study the summery and wintry characteristics and dynamic mechanism of the upper circulation in the Sulu Sea. According to the numerical experiments, it is found that, due to the local monsoon stress cud, the upper circulation in the Sulu Sea is dominated by a weak anticyclonic eddy in summer and a strong cyclonic eddy in winter. Once there is a large outflow via the Sibutu Passage flowing out of the Sulu Sea in summer, the upper circulation in the Sulu Sea may be dominated by a cyclonic eddy instead of the normal anti- cyclonic one. Moreover, in summer, the water exchange between the Sulu Sea and South China Sea via the Mindoro and Balabac Straits might have some effect on the separation position and strength of the northward western boundary current next to the Indo - China Peninsula in the southern South China Sea.

  8. Four new recorded species of marine nanoplanktonic diatoms found in the East China Sea and Huanghai Sea

    Institute of Scientific and Technical Information of China (English)

    Yang Li; Yahui Gao

    2003-01-01

    In a study of species composition of marine nanoplanktonic diatoms (< 20 μm) in watersamples from the East China Sea and Huanghai Sea (Yellow Sea), four diatom species were identifiedby TEM as new records for China. They were Thalassiosira oceanica Hasle, Navicula britannicaHustedt et Aleem, Nitzschia leehyi Fryxell and Synedra indica Taylor. Detailed description of the taxo-nomic characteristics with TEM photographs of the four species and their ecological behavior and distri-bution is given in this paper.

  9. Heavy metals in sea cucumber juveniles from coastal areas of Bohai and Yellow seas, north China.

    Science.gov (United States)

    Jiang, Haifeng; Tang, Shizhan; Qin, Dongli; Chen, Zhongxiang; Wang, Jinlong; Bai, Shuyan; Mou, Zhenbo

    2015-05-01

    The study was undertaken to assess the contents of heavy metals (Cu, Zn, Cr, Pb, Cd, As and Hg) in sea cucumber (Apostichopus japonicus) juveniles from coastal areas of Bohai and Yellow seas in northern China. Sea cucumber juveniles were collected from twenty commercial hatcheries distributed in five coastal cities. The mean concentrations obtained for heavy metals in mg/kg were as follows: Cu (0.179), Zn (2.634), Cr (0.108), Pb (0.065), Cd (0.161), As (0.372), Hg (0.034). All the mean concentrations were below the maximum residual limits set by Chinese legislation, but As in 10 % samples exceeded the safety threshold. Significant differences in contents of Cr, Pb and Hg were found among the five investigated areas. Overall, the heavy metal levels in sea cucumber juveniles were relatively low and more attention should be paid to toxic metals Pb, Cd, As and Hg in future routine monitoring program. PMID:25421712

  10. Sea level change under IPCC-A2 scenario in Bohai, Yellow, and East China Seas

    Directory of Open Access Journals (Sweden)

    Chang-lin CHEN

    2015-10-01

    Full Text Available Because of the environmental and socioeconomic impacts of anthropogenic sea level rise (SLR, it is very important to understand the processes leading to past and present SLRs towards more reliable future SLR projections. A regional ocean general circulation model (ROGCM, with a grid refinement in the Bohai, Yellow, and East China Seas (BYECSs, was set up to project SLR induced by the ocean dynamic change in the 21st century. The model does not consider the contributions from ice sheets and glacier melting. Data of all forcing terms required in the model came from the simulation of the Community Climate System Model version 3.0 (CCSM3 under the International Panel on Climate Change (IPCC-A2 scenario. Simulation results show that at the end of the 21st century, the sea level in the BYECSs will rise about 0.12 to 0.20 m. The SLR in the BYECSs during the 21st century is mainly caused by the ocean mass redistribution due to the ocean dynamic change of the Pacific Ocean, which means that water in the Pacific Ocean tends to move to the continental shelves of the BYECSs, although the local steric sea level change is another factor.

  11. Sea level change under IPCC-A2 scenario in Bohai, Yellow, and East China Seas

    Institute of Scientific and Technical Information of China (English)

    Chang-lin CHEN; Jun-cheng ZUO; Mei-xiang CHEN; Zhi-gang GAO; C-K SHUM

    2014-01-01

    Because of the environmental and socioeconomic impacts of anthropogenic sea level rise (SLR), it is very important to understand the processes leading to past and present SLRs towards more reliable future SLR projections. A regional ocean general circulation model (ROGCM), with a grid refinement in the Bohai, Yellow, and East China Seas (BYECSs), was set up to project SLR induced by the ocean dynamic change in the 21st century. The model does not consider the contributions from ice sheets and glacier melting. Data of all forcing terms required in the model came from the simulation of the Community Climate System Model version 3.0 (CCSM3) under the International Panel on Climate Change (IPCC)-A2 scenario. Simulation results show that at the end of the 21st century, the sea level in the BYECSs will rise about 0.12 to 0.20 m. The SLR in the BYECSs during the 21st century is mainly caused by the ocean mass redistribution due to the ocean dynamic change of the Pacific Ocean, which means that water in the Pacific Ocean tends to move to the continental shelves of the BYECSs, although the local steric sea level change is another factor.

  12. Interannual to decadal variation of spring sea level anomaly in the western South China Sea

    Science.gov (United States)

    Qiu, Fuwen; Fang, Wendong; Pan, Aijun; Cha, Jing; Zhang, Shanwu; Huang, Jiang

    2016-04-01

    Satellite observations of sea level anomalies (SLA) from January 1993 to December 2012 are used to investigate the interannual to decadal changes of the boreal spring high SLA in the western South China Sea (SCS) using the Empirical Orthogonal Function (EOF) method. We find that the SLA variability has two dominant modes. The Sea Level Changing Mode (SLCM) occurs mainly during La Niña years, with high SLA extension from west of Luzon to the eastern coast of Vietnam along the central basin of the SCS, and is likely induced by the increment of the ocean heat content. The Anticyclonic Eddy Mode (AEM) occurs mainly during El Niño years and appears to be triggered by the negative wind curl anomalies within the central SCS. In addition, the spring high SLA in the western SCS experienced a quasi-decadal change during 1993-2012; in other words, the AEM predominated during 1993-1998 and 2002-2005, while the La Niña-related SLCM prevailed during 1999-2001 and 2006-2012. Moreover, we suggest that the accelerated sea level rise in the SCS during 2005-2012 makes the SLCM the leading mode over the past two decades.

  13. Study on numerical simulation and dynamic mechanism of winter- time circulation in the eastern China seas

    Institute of Scientific and Technical Information of China (English)

    HAN Dong; HOU Yijun; WEI Zexun; LIU Xingquan; ZHAO Xixi

    2004-01-01

    An MOM2 based 3-dimentional prognostic baroclinic Z-ordinate model was established to study the circulation in eastern China seas, considering the topography, inflow and outflow on the open boundary, wind stress, temperature and salinity exchange on the sea surface. The results were consistent with observation and showed that the Kuroshio intrudes in large scale into the East China Sea continental shelf East China, during which its water is exchanged ceaselessly with outer sea water along Ryukyu Island. The Tsushima Warm Current is derived from several sources, a branch of the Kuroshio, part of the Taiwan Warm Current, and Yellow Sea mixed water coming from the west of Cheju Island. The water from the west of Cheju Island contributes approximately 13% of the Isushima Warm Current total transport through the Korea Strait. The circulation in the Bohai Sea and Yellow Sea is basically cyclonic circulation, and is comprised of coastal currents and the Yellow Sea Warm Current. Besides simulation of the real circulation, numerical experiments were conducted to study the dynamic mechanism. The numerical experiments indicated that wind directly drives the East China Sea and Yellow Sea Coastal Currents, and strengthens the Korea Coastal Current and Yellow Sea Warm Current. In the no wind case, the kinetic energy of the coastal current area and main YSWC area is only 1% of that of the wind case. Numerical experiments also showed that the Tsushima Warm Current is of great importance to the formation of the Korea Coastal Current and Yellow Sea Warm Current.

  14. Autumn living coccolithophores in the Yellow Sea and the East China Sea

    Institute of Scientific and Technical Information of China (English)

    BAI Jie; GU Xiaoyao; FENG Yuanyuan; JIANG Wensheng; JIN Haiyan; CHEN Jianfang; SUN Jun

    2014-01-01

    An investigation was carried out on living coccolithophores (LCs) distribution in the Yellow Sea and the East China Sea from October 17 to November 24, 2011. A total of 223 samples from different depths were col-lected at 48 stations. Totally 18 taxa belonging to coccolithophyceae were identified using a polarized micro-scope at the 1 000× magnification. The maximum species abundance was found at the outside of Transect P. The dominated species wereGephyrocapsa oceanica, Emiliania huxleyi,Helicosphaera carteri,andAlgiros-phaera robusta.The abundance of coccoliths and cells ranged 0-2 965.73 coccoliths/mL, and 0-119.16 cells/mL, with the average values of 471.00 coccoliths/mL and 23.42 cells/mL, respectively. The LCs in surface layer were mainly observed on the coastal belt and middle part of the survey area. The comparison among Transects A, F, P and E indicated lower species diversity and less abundance in the Yellow Sea than those of the East China Sea. The highest abundance of LCs was found in transect F and P. The coccolith abundance increased slightly from surface to bottom in the water column, but the highest value of the cell abundance was observed in the depth of 10-30 m. Temperature, depth and nutrient concentration were suggested as the major environmental factors controlling the distribution and species composition of LCs in the studying area based on canonical correspondence analysis (CCA).

  15. The Issue of China' s Land & Sea Frontiers and the Proper Response%The Issue of China' s Land & Sea Frontiers and the Proper Response

    Institute of Scientific and Technical Information of China (English)

    Jin Canrong

    2012-01-01

    China is located at the eastern end of Eurasia and on the western side of the Pacific. Since ancient times, China has had both land and sea territory. In addition, China has common land or sea borders with many neighboring countries. So China has always regarded her land and maritime frontiers as important. Much of China' s history has been dominated by a feudal farming civilization and so border problems were largely restricted to land boundaries.

  16. Trends of sea level rise in the South China Sea during the 1990s: An altimetry result

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Using 7 years of TOPEX/POSEIDON satellite altimetry data, we have identified a general trend of sea level rising in the South China Sea between January 1993 and December 1999. The estimated bulk rising rate of the entire basin is ~1 cm/a. The rise of sea level appears to be spatially non-homogeneous, which shows a highest rate of 2.7 cm/a in the deep basin west of Luzon and generally Iow (even negafive) rates over the shallow continental shelves. It is believed that the observed rapid rising of sea level is a regional phenomenon and is mainly caused by warming of the upper layer of the South China Sea, which showed a bulk warming rate of 0.15℃/a in the same period. It is also suggested that the observed rising trend is mainly a decadal signal, which is possibly associated with decadal variation of the Pacific warm pool region.

  17. Water-transparency (Secchi Depth) monitoring in the China Sea with the SeaWiFS satellite sensor

    Science.gov (United States)

    He, Xianqiang; Pan, Delu; Mao, Zhihua

    2004-10-01

    Water transparency (Secchi depth) is a basic parameter that describes the optical property of water, and it is a traditional item measured in situ. The traditional method of monitoring water transparency is the in-situ measurement by ship. However, because of its inherent shortcoming, this in situ method can not satisfy the requirement of the large-scale, quick and real-time monitoring of the water transparency. Therefore, it must be combined with the remote sensing technology to fulfill the monitoring of the water transparency. This paper studies the water transparency monitoring in China Sea by using SeaWiFS satellite sensor. First, the inversing algorithm of water transparency is introduced briefly, which based on the radiative transfer theory and bio-optical model of water. Second, the accuracy of the algorithm is validated by using the large-scale in-situ data from the Japan Meteorological Agency (JMA), which covered most of the Northwest Pacific ocean. The result shows the inversing relative error of water transparency is 22.6% by using the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) data, and it is even better in the open sea. Third, using this algorithm and SeaWiFS data, a remote sensing product data set of water transparency in China Sea was generated. Finally, we present the analysis of seasonal distribution and fluctuation patterns of water transparency in China Sea by using the generated remote sensing product collection of water transparency.

  18. Distribution of heavy metals and nutrients in rainwater in coastal regions between the southern Yellow Sea and East China Sea

    Institute of Scientific and Technical Information of China (English)

    LIU Changling; ZHANG Guosen; REN Hongbo; ZHANG Jing

    2005-01-01

    Rainwater samples were collected in series in Qianliyan Island (southern Yellow Sea) and Shengsi Archipelago (East China Sea) between May 2000 and May 2002, chemical analysis for pH values,concentrations of heavy metals (Cu, Pb, Zn and Cd) and nutrients (NH4+, NO3-, PO43-, SiO32-) were performed.Results indicate that concentrations of most of the heavy metals and nutrients in rainwater show clear seasonal variation, i.e. high level in winter and low level in summer. Regionally, concentrations are higher in the southern Yellow Sea than in the East China Sea, but the annual input of heavy metals into oceans by wet deposition is similar in both stations. However, the input of nutrients by wet deposition in the East China Sea is 2-3 times higher than that in the southern Yellow Sea. In individual, Pb and PO43- are input to the sea mainly by dry deposition; whereas Cu, Zn, Cd and N compounds are input dominantly by wet deposition, the N/P ratios in the rainwater from two stations are much higher than those in seawater, showing a significant impact of atmospheric wet deposition on marine production and biogeochemical circulation of nutrients in these sea regions.

  19. Potential impacts of Three Gorges Dam in China on the ecosystem of East China Sea

    Institute of Scientific and Technical Information of China (English)

    WANG Baodong; BROCKMANN Uwe

    2008-01-01

    The Changjiang River in China was dammed in 2003.The possible changes in matters fluxes from the river downstream after the completion of Three Gorges Dam and their potential impacts on the ecosystem of the East China Sea are discussed.The estuarine and coastal waters in the East China Sea were heavily fertilized by the inflow of nutrient-rich freshwater from the Changjiang River, which has led to severe eutrophication and frequent harmful algal blooms,thus worsening the ecosystem health in this area.Analy- sis showed that the nutrient loadings are very likely to be reduced in the lower Changjiang River due to the construction of Three Gorges Dam.Especially for the total phosphorus,the discharges to the East China Sea will be reduced by one-third,which would relieve the severe eutrophication in this area.However,the expected decrease in the riverine silicate discharge would lead the ra- tio of silicon to nitrogen to be much less than 1 in the estuarine and coastal waters and thus may cause an elevation of flagellate growth.The changes in the annual water discharges and their seasonal distributions below the dam will be minor.Reduction of suspended particulate matter loading,due to the sedimentation behind the dam,will reduce the nutrient loadings of the particulate form especially for phosphorus,and decrease the turbidity of estuarine and coastal waters.On the other hand,this may enhance the erosion of the delta and the coasts as well as modifythe benthic ecosystem.

  20. The circulation in the southern Huanghai Sea and northern East China Sea in June 1999

    Institute of Scientific and Technical Information of China (English)

    Yaochu Yuan; Yonggang Liu; Mingyu Zhou; Arata Kaneko; Zhou Yuan; Noriaki Gohda

    2003-01-01

    On the basis of hydrographic data and current measurement (the mooring system, vessel-mounted ADCP and toward ADCP) data obtained in June 1999, the circulations in the southern Huang-hai Sea (HS) and northern East China Sea (ECS) are computed by using the modified inverse method.The Kuroshio flows northeastward through eastern part of the investigated region and has the main coreat Section PN, a northward flow at the easternmost part of Section PN, a weaker anti-cyclonic eddy be-tween these two northward flows, and a weak cyclonic eddy at the western part of Section PN. Theabove current structure is one type of the current structures at Section PN in ECS. The net northwardvolume transport (VT) of the Kuroshio and the offshore branch of Taiwan Warm Current (TWCOB)through Section PN is about 26.2× 106 m3/s in June 1999. The VT of the inshore branch of TaiwanWarm CArrent (TWCIB) through the investigated region is about 0.4 × 106 m3/s. The Taiwan WarmCurrent (TWC) has much effect on the currents over the continental shelf. The Huanghai Sea CoastalCurrent (HSCC) flows southeastward and enters into the northwestern part of investigated region, andflows to turn cyclonically, and then it flows northeastward, due to the influences of the Taiwan WarmCurrent and topography. There is a cyclonic eddy south of Cheju Island where the Huanghai Sea CoastalCurrent flows to turn cyclonically. It has the feature of high dense and cold water. The uniform and coldwater is occurred in the layer from about 30 m level to the bottom between Stations C306 and C311 atthe northernmost Section C3. It is a southern part of the Huanghai Sea Cold Water Mass (HSCWM).

  1. Comparison of TOPEX/POSEIDON altimeter derived wave period with ocean buoy data in the East China Sea and South China Sea

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Altimeter wave period data obtained from continental shelf seas are analyzed in this paper.Empirical models are introduced for zero up-crossing and peak wave period calculation with TOPEX/POSEIDON data. Their performances are assessed using independent validation dataset in four sites in the open ocean of China. To provide more accurate wave period estimation, new coefficients are applied to reliable in situ data. Comparison of our estimated the wave periods with new linear calibrations based on independent data of Seapac 2100 deployed in the East China Sea and South China Sea showed that the accuracy was improved over estimates determined from earlier empirical models. Regional analysis indicated that the wave period model works better under wind sea condition.

  2. Optical absorption and scattering properties in the East China Sea

    Science.gov (United States)

    Zhang, Xuan; He, Xian-qiang; Chen, Xiao-yan; Hao, Zeng-zhou; Huang, Haiqing; Zhu, Qiankun

    2011-11-01

    The absorption and particulate backscattering coefficients are the basic parameters of the water inherent optical properties (IOPs), which are also the basic parameters for the development and validation of the semi-analysis models of the ocean color remote sensing. In this work, the absorption and backscattering coefficients in the East China Sea (ECS) were measured in the summer and winter of 2009 using the three in-situ optical instruments, including the WET Labs acs, and the HOBI Labs HydroScat-6. Based on the in-situ measured data, the distribution of the absorption and backscattering coefficients in the ECS are analyzed. The results show that in the summer the water absorption coefficient at 440nm (a(440nm),excluding the absorption of the pure sea water) in the surface layer is ranged from 0.022 to 0.067 m-1, and the particulate backscattering coefficient at 442nm(bbp(442nm), is between 0.00064 and 0.03274 m-1. As a whole, both of the absorption and backscattering coefficients decrease with the offshore direction, and the high values located at the mouth of Changjiang River. In the winter, a(440nm) is between 0.051 and 0.887 m-1, and bbp(442nm) is ranged from 0.000639 to 0.14614 m-1 at the surface layer. The spatial distributions in winter are similar as the summer, with the high value in the coast and low value in the offshore. The absorption and backscattering coefficients in winter are significantly larger than the summer's, especially in coastal area near the mouth of Changjiang River, which maybe caused by the southward Fujian-Zhejiang coastal current occurring in winter. As the vertical profile distributions, we find that both of the absorption and backscattering coefficients present a layer structure, which caused by the stratification of the sea water in the summer; while in the winter, affected by the strong wind disturbing, both of the absorption and backscattering coefficients are thoroughly vertical mixing. To our knowledge, it is the first time

  3. Impact of Sea Surface Temperature Front on Stratus-Sea Fog over the Yellow and East China Seas-A Case Study with Implications for Climatology

    Institute of Scientific and Technical Information of China (English)

    LI Man; ZHANG Suping

    2013-01-01

    A stratus-sea fog event that occurred over the Yellow and East China Seas on 3 June 2011 is investigated using observations and a numerical model,with a focus on the effects of background circulation and Sea Surface Temperature Front (SSTF) on the transition of stratus into sea fog.Southerly winds of a synoptic high-pressure circulation transport water vapor to the Yellow Sea,creating conditions favorable for sea fog/stratus formation.The subsidence from the high-pressure contributes to the temperature inversion at the top of the stratus.The SSTF forces a secondary circulation within the ABL (Atmospheric Boundary Layer),the sinking branch of which on the cold flank of SSTF helps lower the stratus layer further to reach the sea surface.The cooling effect over the cold sea surface counteracts the adiabatic warming induced by subsidence.The secondary circulation becomes weak and the fog patches are shrunk heavily with the smoothed SSTF.A conceptual model is proposed for the transition of stratus into sea fog over the Yellow and East China Seas.Finally,the analyses suggest that sea fog frequency will probably decrease due to the weakened SSTF and the reduced subsidence of secondary circulation under global warming.

  4. On the tidally driven circulation in the South China Sea: modeling and analysis

    Science.gov (United States)

    Nelko, Varjola; Saha, Abhishek; Chua, Vivien P.

    2014-03-01

    The South China Sea is a large marginal sea surrounded by land masses and island chains, and characterized by complex bathymetry and irregular coastlines. An unstructured-grid SUNTANS model is employed to perform depth-averaged simulations of the circulation in the South China Sea. The model is tidally forced at the open ocean boundaries using the eight main tidal constituents as derived from the OSU Tidal Prediction Software. The model simulations are performed for the year 2005 using a time step of 60 s. The model reproduces the spring-neap and diurnal and semidiurnal variability in the observed data. Skill assessment of the model is performed by comparing model-predicted surface elevations with observations. For stations located in the central region of the South China Sea, the root mean squared errors (RMSE) are less than 10 % and the Pearson's correlation coefficient ( r) is as high as 0.9. The simulations show that the quality of the model prediction is dependent on the horizontal grid resolution, coastline accuracy, and boundary locations. The maximum RMSE errors and minimum correlation coefficients occur at Kaohsiung (located in northern South China Sea off Taiwan coast) and Tioman (located in southern South China Sea off Malaysia coast). This may be explained with spectral analysis of sea level residuals and winds, which reveal dynamics at Kaohsiung and Tioman are strongly influenced by the seasonal monsoon winds. Our model demonstrates the importance of tidally driven circulation in the central region of the South China Sea.

  5. A new evaporation duct climatology over the South China Sea

    Science.gov (United States)

    Shi, Yang; Yang, Kunde; Yang, Yixin; Ma, Yuanliang

    2015-10-01

    The climatology of evaporation ducts is important for shipborne electromagnetic system design and application. The evaporation duct climatology that is currently used for such applications was developed in the mid 1980s; this study presents efforts to improve it over the South China Sea (SCS) by using a state-of-the-art evaporation duct model and an improved meteorology dataset. This new climatology provides better evaporation duct height (EDH) data over the SCS, at a higher resolution of 0.312°×0.313°. A comparison between the new climatology and the old one is performed. The monthly average EDH in the new climatology is between 10 and 12 m over the SCS, higher than that in the old climatology. The spatiotemporal characteristics of the evaporation duct over the SCS in different months are analyzed in detail, based on the new climatology.

  6. Geochemistry of Soil Formation in south China Sea Islands

    Institute of Scientific and Technical Information of China (English)

    GONGZI-TONG; HUANGBIAO

    1995-01-01

    The soils in South China sea Islands(SCSI)were divided into three types,nmaely,phospho-calc soils,skeletisols and coastic solonchake,which were derived from bio-clastic and strongly calcareous sediments.In comparison with their parent materials,the phospho-Calc soils have higher contents of P,Zn Cu,Ba,and Cd,which tend to increase gradually with time,and lower contents of Mg,Ca,Sr,B,V,Pb,and Mo,which tend to decrease by degrees with time,The above-mentioned constituents in skeletisols and coastic solonchaks are similar to those in their parent materials except for P and Na,The factors affecting element distribution are mainly special bioclimate and parent material,meanwhile,resulting in the remakable influence on element distribution through soil-forming time.

  7. The statistic inversion algorithms of water constituents for the Huanghai Sea and the East China Sea

    Institute of Scientific and Technical Information of China (English)

    TANG Junwu; WANG Xiaomei; SONG Qingjun; LI Tongji; CHEN Jiezhong; HUANG Haijun; REN Jingping

    2004-01-01

    A group of statistical algorithms are proposed for the inversion of the three major components of Case-Ⅱ waters in the coastal area of the Huanghai Sea and the East China Sea. The algorithms are based on the in situ data collected in the spring of 2003 with strict quality assurance according to NASA ocean bio-optic protocols. These algorithms are the first ones with quantitative confidence that can be applied for the area. The average relative error of the inversed and in situ measured components' concentrations are: Chl-a about 37%, total suspended matter (TSM) about 25%,respectively. This preliminary result is quite satisfactory for Case-Ⅱ waters, although some aspects in the model need further study. The sensitivity of the input error of 5% to remote sensing reflectance (Rrs) is also analyzed and it shows the algorithms are quite stable. The algorithms show a large difference with Tassan's local SeaWiFS algorithms for different waters, except for the Chl-a algorithm.

  8. Climatic changes in the northern South China Sea since the last glacial maximum

    OpenAIRE

    Kong, Deming; 孔德明

    2014-01-01

    The principal aim of this thesis is to reconstruct climatic changes in the open sea and coastal area of northern South China Sea (SCS) since the Last Glacial Maximum (LGM), and investigate its relationship with the East Asian monsoons, as well as insolation and sea level changes. The Sea Surface Temperature (SST) derived from long-chain alkenones in the open sea sediment core NS02G increased by 5°C and generally followed the sea level rise pattern from the LGM to mid Holocene. The SST kept in...

  9. Statistical Prediction of the South China Sea Surface Height Anomaly

    Directory of Open Access Journals (Sweden)

    Caixia Shao

    2015-01-01

    Full Text Available Based on the simple ocean data assimilation (SODA data, this study analyzes and forecasts the monthly sea surface height anomaly (SSHA averaged over South China Sea (SCS. The approach to perform the analysis is a time series decomposition method, which decomposes monthly SSHAs in SCS to the following three parts: interannual, seasonal, and residual terms. Analysis results demonstrate that the SODA SSHA time series are significantly correlated to the AVISO SSHA time series in SCS. To investigate the predictability of SCS SSHA, an exponential smoothing approach and an autoregressive integrated moving average approach are first used to fit the interannual and residual terms of SCS SSHA while keeping the seasonal part invariant. Then, an array of forecast experiments with the start time spanning from June 1977 to June 2007 is performed based on the prediction model which integrates the above two models and the time-independent seasonal term. Results indicate that the valid forecast time of SCS SSHA of the statistical model is about 7 months, and the predictability of SCS SSHA in Spring and Autumn is stronger than that in Summer and Winter. In addition, the prediction skill of SCS SSHA has remarkable decadal variability, with better phase forecast in 1997–2007.

  10. Sedimentation rate control on diagenesis, East China Sea sediments

    Science.gov (United States)

    Zheng, Yan; Zheng, Hongbo; Kissel, Catherine; Laj, Carlo

    2011-08-01

    Diagenesis of ferrimagnetic minerals can alter the magnetic properties, erasing partially or entirely the original paleomagnetic and paleoclimatic signals, especially on continental margins where sedimentation rates are usually high. Understanding the mechanisms by which magnetic particles are affected by diagenesis is therefore critical for retrieving paleomagnetic and paleoclimatic information from sediments. High-resolution magnetic analysis was carried out on rapidly deposited (0.4-20 mm/year) Holocene sediments from the East China Sea (ECS) inner continental shelf. The primary magnetic mineral assemblage in the sediment core contains ferrimagnetic minerals, such as magnetite, with minor contributions from hematite. The magnetic properties vary down-core in two steps, due to post-depositional reductive diagenesis. The first occurs at depths of 0.15-1.1 m and is characterized by reduction of both magnetite and hematite in suboxic sediments. The suboxic-sulfate boundary (SSB) is therefore located at 1.1 m. We demonstrate that the depth of the SSB has negative relation to the average sedimentation rate in Chinese marginal seas. The second step change in magnetic properties occurs at 3.2-5.8 m, and contains two intervals with extremely low magnetic mineral content, each corresponding to dissolution fronts associated with the former and present position of the sulfate-methanic transition (SMT). These two intervals correlate well with abrupt changes in sedimentation rate and separate the anoxic zone into two parts: the sulfidic zone and the methanic zone. Our study suggests that sedimentation rate provides a dominant control on magnetic mineral diagenesis, at least in the Chinese marginal seas, which controls not only the type of redox zonation, but also the thicknesses of diagenetic zones.

  11. Intercomparison of three South China Sea circulation models

    Institute of Scientific and Technical Information of China (English)

    DU Yan; WANG Dongxiao; ZHOU Weidong; WANG Weiqiang; LIU Xiongbin

    2004-01-01

    Three numerical oceanic circulation models: POM(Princeton ocean model), MICOM(Miami isopycnal coordinates ocean model) and GFDL model, which adopt sigma coordinate, isopycnal coordinate and depth coordinate respectively,are used in the South China Sea(SCS) circulation modeling. Model domain has the same topography, grid resolution,initial conditions and surface boundary conditions. The maximum ocean depth is set as 1000 m. Grid resolution is 0.5°×0.5°.Initial conditions are supplied by climatological temperature and salinity data in January. Climatological wind stress, surface temperature and salinity are used as surface forcing. Lateral boundaries take enclosed boundary conditions artificially. Focusing on the common point of different ocean circulation models, the circulation pattern in winter and summer, sea surface height in the northern SCS, seasonal cycle of the mixed layer thickness in the southem SCS,barotropic stream function in winter are selected to carry out intercomparison. In winter, a strong cyclonic gyre occupies the whole SCS. In summer, a strong anticyclonic gyre occupies the southern SCS and a weak cyclonic gyre occupies the northern SCS. The thickness of the mixed layer shows bimodal features in the southern SCS. Sea surface height anomaly(SSHA) in the northern SCS has an eastward propagating feature, in agreement with the remote sensing observation. Barotropic stream functions indicate that the circulation of the upper ocean is mainly forced by inputting of wind stress curl under closed boundary conditions. In addition, three models also show distinct differences. The basinscale circulation fiom MICOM is distinct. Output of POM has more mesoscale eddies than others. GFDL model seems good at simulating westward intensification.

  12. Limit analysis of extended reach drilling in South China Sea

    Institute of Scientific and Technical Information of China (English)

    Gao Deli; Tan Chengjin; Tang Haixiong

    2009-01-01

    Extended reach wells (ERWs), especially horizontal extended reach well with a high HD (horizontal displacement) to TVD (true vertical depth) ratio, represent a frontier technology and challenge the drilling limitations.Oil and gas reservoir in beaches or lakes and offshore can be effectively exploited by using extended reach drilling (ERD) technology.This paper focuses on the difficult technological problems encountered during exploiting the Liuhua 11-1 oil field in the South China Sea, China.Emphasis is on investigating the key subjects including prediction and control of open hole limit extension in offshore ERD, prediction of casing wear and its prevention and torque reduction, φ244.5mm casing running with floating collars to control drag force, and steerable drilling modes.The basic concept of limit extension in ERD is presented and the prediction method for open hole limit extension is given in this paper.A set of advanced drilling mechanics and control technology has been established and its practical results are verified by field cases.All those efforts may be significant for further investigating and practicing ERD limit theory and control technology in the future.

  13. South China Sea Territorial Disputes and Sino-Philippine Trade

    Institute of Scientific and Technical Information of China (English)

    FANG; WANG

    2015-01-01

    As political factors affect trade activities greatly, this paper considers whether a series of political events have had a negative impact on Sino-Philippine trade relations. Of particular concern is the influence on bilateral relations and the Philippines’ domestic economy from political and diplomatic tensions between China and the Philippines caused by territorial disputes in the South China Sea. Political events are divided into two levels, general conflicts and serious conflicts, which are analyzed from the perspectives of both overall level and product level to present their final impact on trade. This research finds that territorial disputes between the two countries deteriorated trade, as the volume of trade usually decreased distinctly after conflicts. The negative impact on trade generated by serious conflicts usually occurred more rapidly and on a larger scale. The effect of trade deterioration caused by political events weakened over time. Furthermore, after serious conflicts, although the volume of trade of certain products decreased temporarily, it rebounded quickly or even increased soon. However, industrial equipment or industrial raw materials trade activities between the two countries were basically independent of the conflicts’ impact.

  14. Chemical and temperature profile data from CTD casts in the East China Sea, Sea of Japan, and North Pacific Ocean (NODC Accession 9700022)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Chemical and temperature profile data were collected from CTD casts in the East China Sea, Sea of Japan, and North Pacific Ocean. Data were submitted by the Japan...

  15. The Delimitation of East China Sea Continental Shelf:Sino-Japanese Disputes from the Perspective of International Law

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The East China Sea which covers a total area of 750,000 square kilometers is a semi-closed sea lying between the eastern coast of China’s mainland and the Pacific Ocean, bounded on the west by China, on the east by the Kyushu and the Ryukyu Islands of Japan, and on the north by Jichu Island of the Republic of Korea (ROK) and the Yellow Sea, and connected with the South China Sea by the Taiwan Strait on

  16. Transition of Quaternary glacial cyclicity in deep-sea records at Nansha, the South China Sea

    Institute of Scientific and Technical Information of China (English)

    WANG; Pinxian

    2001-01-01

    [1]Shackleton. N. J., Opdyke, N. D., Oxygen isotope and paleomagnetic stratigraphy of Pacific core V28-239: Late Plio cene to Latest Pleistocene, Mem. Geol. Soc. Am., 1976, 145: 449-464.[2]Ding, Z., Liu, D., New Development of China Loess Research (1) Loess Stratigraphy, Quaternary Research (in Chinese),1989, 1: 24-35.[3]Raymo, M. E., Oppo, D. W., Curry. W., The mid-Pleistocene climate transition: A deep sea carbon isotopic perspective,Paleoceanography, 1997, 12(4): 546-559.[4]PrellW. L., Oxygen and carbon isotope stratigraphy for the Quaternary of Hole 502B: Evidence for two modes of isotopic variability, in Init. Repts. DSDP (eds. Prell and W. L., Gardner, J. V.), 1982, 68: 455-464.[5]Shackleton. N. J., The 100,000-year ice-age cycle identified and found to lag temperature, carbon dioxide, and orbital eccentricity, Science, 2000, 289: 1897-1902.[6]Rutherford, S., D'Hondt, S., Early onset and tropical forcing of 100,000-year Pleistocene glacial cycles, Nature, 2000, 408:72-75.[7]Berger, W. H., Bickert, T., Jansen, E. et al., The central mystery of the Quaternary Ice Age, Oceanus, 1993, 36(4): 53-56.[8]Raymo, M. E., The timing of major climate terminations, Paleoceanography, 1997, 12(4): 577-585.[9]Berger, W. H., Jansen, E., Mid-Pleistocene climate shift: The Nansen connection, Geophysical Monograph, 1994, 84:295-311.[10]Clark, P. C., Pollanrd, D., Origin of the middle Pleistocene transition by ice sheet erosion of regolith, Paleoceanography,1998, 13: 1-19.[11]Wang, P., Prell, W., Blum, P. et al. Initial Reports 184, Ocean Drilling Program in Proceedings of the ODP [CD-ROM].Texas: Texas A&M University, College Station, 2000, 1-103.[12]Zhao, Q., Jian, Z., Liang, J. et al., Neogene Oxygen Isotopic Stratigraphy, ODP Site 1148, northern South China Sea, Sci ence in China, Ser. D,2001, 44(10): 934-942.[13]Zhao, Q., Jian, Z., Li, B. et al., Microtektites in the Middle Pleistocene deep-sea sediments of the South China

  17. Distributions and sea-to-air fluxes of nitrous oxide in the South China Sea and the West Philippines Sea

    Science.gov (United States)

    Tseng, Hsiao-Chun; Chen, Chen-Tung Arthur; Borges, Alberto V.; DelValls, T. Angel; Lai, Chao-Ming; Chen, Ting-Yu

    2016-09-01

    Approximately 600 water samples from the South China Sea (SCS) and 250 water samples from the West Philippines Sea (WPS) were collected during seven cruises from August 2003 to July 2007 to determine nitrous oxide (N2O) distributions between the surface and a maximum depth of 4250 m. In the SCS, the average surface N2O concentration exceeded the atmospheric equilibrium concentration (on average 132±23%); however in the WPS, the surface N2O concentration was lower than the atmospheric equilibrium concentration (on average 90±22%). The N2O concentration reached a maximum (~23 nmol L-1) in the WPS at 800-1000 m, and (~28 nmol L-1) at a shallower depth of around 600-800 m in the SCS, owing to vertical mixing and intensive upwelling in the SCS. In the SCS, the surface N2O concentration was 7.59±1.32 nmol L-1 and the calculated sea-to-air flux was 5.5±3.9 μmol m-2 d-1. The surface N2O concentration in the WPS, 5.19±1.26 nmol L-1, was lower than that in the SCS. The WPS is a sink for N2O and the calculated sea-to-air flux was -1.7±3.9 μmol m-2 d-1. The SCS emitted 19.3×106 mol d-1 N2O to the atmosphere and exported 8.5×106 mol d-1 N2O to the WPS during the wet season.

  18. Introducing Seawater China for Sustainablefrom Bohai Sea to WestDevelopment in the Area

    Institute of Scientific and Technical Information of China (English)

    ChenChangli

    2004-01-01

    Sustained and profound aridization process in north-west China in Tertiary and Quaternary period and time of mankind history are discussed. The rain-creased function of 3 set high mountain condensation systems in north-west China is recognized once more. A sandstorm happened on 20th March 2002 in Alasan and Ejinaqi areas was very strong and arrived in Japan and Korea. For saving Alasan area from sandstorm a way of introducing sea water from Bohai to Alasan has been proposed. Four problems are replied in this paper. It is concluded that introducing sea water from Bohai to west China is the best way for sustainable development of west China.

  19. Reanalysis of the Atmospheric Flux of Nutrient Elements to the Southern Yellow Sea and the East China Sea

    Institute of Scientific and Technical Information of China (English)

    Wan Xiaofang; Wu Zengmao; Chang Zhiqing

    2003-01-01

    Based on the recent research results on dry and wet deposition of nutrient elements and sulphate, we estimate the atmospheric flux of nutrient elements and sulphate to the southern Yellow Sea and the East China Sea in each season. The results suggest that the concentrations of nutrient elements and sulphate in aerosol and precipitation show an apparent seasonal cycle with the maximum values in winter and the minimum values in summer. Depositions of nitrate and sulphate are dominated by wet deposition, while the deposition for phosphate is mainly dry deposition. Moreover, compared with the riverine inputs, the atmospheric deposition may be the main source of dissolved inorganic nutrients in the southern Yellow Sea and the East China Sea.

  20. Water Masses in the South China Sea and Water Exchange between the Pacific and the South China Sea

    Institute of Scientific and Technical Information of China (English)

    LI Fengqi; LI Lei; WANG Xiuqin; LIU Changle

    2002-01-01

    Water masses in the South China Sea (SCS) were identified and analyzed with the data collected in the summer and winter of 1998. The distributions of temperature and salinity near the Bashi Channel (the Luzon Strait) were analyzed by using the data obtained in July and December of 1997. Based on the results from the data collected in the winter of 1998,waters in the open sea areas of the SCS were divided into six water masses: the Surface Water Mass of the SCS (S), the Subsurface Water Mass of the SCS (U), the Subsurface-Intermediate Water Mass of the SCS (UI), the Intermediate Water Mass of the SCS (I), the Deep Water Mass of the SCS (D) and the Bottom Water Mass of the SCS(B). For the summer of 1998,the Kuroshio Surface Water Mass (KS) and the Kuroshio Subsurface Water Mass (KU) were also identified in the SCS. But no Kuroshio water was found to pass the 119.5°E meridian and enter the SCS in the time of winter observations. The Sulu Sea Water (SSW) intruded into the SCS through the Mindoro Channel between 50-75 m in the summer of 1998. However, the data obtained in the summer and winter of 1997 indicated that water from the Pacific had entered the SCS through the northern part of the Luzon Strait in these seasons, but water from the SCS had entered the Pacific through the southern part of the Strait. These phenomena might correlate with the 1998 El-Nino event.

  1. Late Oligocene sedimentary environments and provenance abrupt change event in the northern South China Sea

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A significant change in composition was recorded in late Oligocene sediments from the northern South China Sea.This abrupt event coincided with the seafloor spreading axis jump across the Oligocene/Miocene boundary,leading to sedimentation breaks and slumps as well as obvious changes in sediment geochemical composition,and representing the greatest tectonic activity in the South China Sea region since the Oligocene.Through this tectonic event,the sedimentary environment in the Baiyun sag area transformed from a continental shelf in the late Oligocene to a continental slope since the early Miocene,the provenance of the sediments changed from neighboring areas to the hinterland of the South China block,and the sea level rose since the early Miocene in the area.Therefore,this abrupt change event has a profound influence on the evolution of petroleum offshore in the northern South China Sea.

  2. Improvement of the South China Sea Prediction System Using NSCAT Winds, A Research Project Outline

    OpenAIRE

    Peter C. Chu

    1999-01-01

    Peter C. Chu, Principal Investigator. Improvement of the South China Sea Prediction System Using NSCAT Winds, NASA/JPL (through California State University, Monterey Bay) NASA/JPL (through California State University

  3. Tectonics and Sedimentary Basins of the South China Sea: Challenges and Progresses

    Institute of Scientific and Technical Information of China (English)

    Zhou Di; Yao Bochu

    2009-01-01

    @@ The special issue "Tectonics and Sedimentary Basins of the South China Sea" consists of 19 articles arranged in the order of deep structure,general tectonics,tectonic modeling,and sedimentary basins especially the deepwater sedimentary basins.

  4. DETERMINATION OF SOUTH CHINA SEA MONSOON ONSET AND EAST ASIAN SUMMER MONSOON INDEX

    Institute of Scientific and Technical Information of China (English)

    GAO-Hui; LIANG Jian-yin

    2006-01-01

    Results of the definition of South China Sea summer monsoon onset date and East Asian summer monsoon index in recent years are summarized in this paper. And more questions to be resolved are introduced later.

  5. A Preliminary Study of the Gas Hydrate Stability Zone in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    金春爽; 汪集旸

    2002-01-01

    Based on the analysis of sea-bottom temperature and geothermal gradient, and by means of the phaseboundary curve of gas hydrate and the sea-bottom temperature versus water depth curve in the South China Sea, thispaper studies the temperature and pressure conditions for gas hydrate to keep stable. In a marine environment, methanehydrate keeps stable at water depths greater than 550 m in the South China Sea. Further, the thickness of the gas hydratestability zone in the South China Sea was calculated by using the phase boundary curve and temperature-depth equations.The result shows that gas hydrate have a better perspective in the southeast of the Dongsha Islands, the northeast of theXisha Islands and the north of the Nansha Islands for thicker stability zones.

  6. Deep Structures of the Palawan and Sulu Sea and Their Implications for Opening of the South China Sea

    Science.gov (United States)

    Liu, W.; Li, C. F.; Li, J.; Fairhead, D.; Zhou, Z.

    2014-12-01

    Compared to the northern South China Sea continental margin, the deep structures and tectonic evolution of the Palawan and Sulu Sea and ambient regions are not well understood so far. However, this part of the southern continental margin and adjacent areas embed critical information on the opening of the South China Sea (SCS). We carry out geophysical investigations using regional magnetic, gravity and reflection seismic data. Analytical signal amplitudes (ASA) of magnetic anomalies are calculated to depict the boundaries of different tectonic units. Curie-point depths are estimated from magnetic anomalies using a windowed wavenumber-domain algorithm. Application of the Parker-Oldenburg algorithm to Bouguer gravity anomalies yields a 3D Moho topography. The Palawan Continental Block (PCB) is defined by quiet magnetic anomalies, low ASA, moderate depths to the top and bottom of the magnetic layer, and its northern boundary is further constrained by reflection seismic data and Moho interpretation. However, the continent-ocean transition zone between the PCB and the SCS is characterized by hyper-extended continental crust intruded with magmatic bodies. The NW Sulu Sea is interpreted as a relict oceanic slice and the geometry and position of extinct trench of the Proto South China Sea (PSCS) is further constrained. With additional age constraints from inverted Moho and Curie-point depths, we confirm that the spreading of the SE Sulu Sea started in the Early Oligocene/Late Eocene due to the subduction of the PSCS, and terminated in the Middle Miocene by the obduction of the NW Sulu Sea onto the PCB. According to the newly constrained age of SE Sulu Sea, we also estimate the approximate extent, spreading rate and subducting rate of original SE Sulu Sea.

  7. The assimilation experiment in the southwestern South China Sea in summer 2000

    Institute of Scientific and Technical Information of China (English)

    XIAO Xianjun; WANG Dongxiao; XU Jianjun

    2006-01-01

    We performed an assimilation experiment of the southern South China Sea in summer 2000, and the altimeter data were assimilated into Princeton Ocean Model (POM). The result was evaluated with the in situ data. There were obvious improvements of the currents in the southern South China Sea, and the modeling uncertainty coming from the error of wind stress forcing was reduced.This experiment provides us a new idea about improving the modeling of the ocean currents.

  8. Advances in Studying Oceanic Circulation from Hydrographic Data with Applications in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    王桂华; 李荣凤; 闫长香

    2003-01-01

    Methods for studying oceanic circulation from hydrographic data are reviewed in the context of their applications in the South China Sea. These methods can be classified into three types according to their different dynamics as follows: (1) descriptive methods, (2) diagnostic methods without surface and bottom forcing, and (3) diagnostic methods with the above boundary forcing. The paper discusses the progress made in the above methods together with the advancement of study in the South China Sea circulation.

  9. Mud Volcanoes from the Beaufort Sea to the South China Sea

    Science.gov (United States)

    Lundsten, E. M.; Paull, C. K.; Caress, D. W.; Dallimore, S.; Melling, H.; Liu, C. S.; Anderson, K.; Gwiazda, R.

    2015-12-01

    The detailed morphology of five submarine mud volcanoes were surveyed using an Autonomous Underwater Vehicle (AUV) developed at the Monterey Bay Aquarium Research Institute. Mud volcanoes are constructional features built by extrusion of gas, subsurface fluids and fine-grained sediment. Two surveys covering four submarine mud volcanoes were conducted on the CCGS Sir Wilfred Laurier in the Beaufort Sea in the Canadian Arctic. A survey of one mud volcano was conducted on the Taiwanese Ocean Research V in the South China Sea, SE of Taiwan. The AUV carried a multibeam sonar, a 1-6 kHz chirp sub-bottom profiler, and a110 kHz sidescan, and obtained overlapping multibeam bathymetric coverage at a vertical resolution of 0.15 m with a horizontal footprint of 0.9 m and chirp seismic-reflection profiles with a vertical resolution of 0.11 m. Mud volcanoes were either flat topped or conical. The conical mud volcano off Taiwan had a diameter of ~2 km and 10° side slopes; the conical feature in the Beaufort Sea had a diameter of ~1.5 km and 4° side slopes. The sides of the conical mud volcanoes were smooth, suggesting they were formed by sediment flows that emanate from a vent on their crests. The flanks of the conical mud volcanoes characteristically had very low acoustic reflectivity, but one single high reflectivity trail from the crest of the Beaufort Sea mud volcano indicates a recent flow. Three mud volcanoes in the Beaufort Sea formed circular, flat-topped plateaus that are up to ~1.1 km in diameter and elevated up to 30 m from the surrounding seafloor. The fine scale morphology and reflectivity on these plateaus show low relief, concentric, and ovoid circles that appear to be mud boils probably associated with eruptive events of varying ages at shifting vent sites. The different mud volcano shapes are attributed to variations in the viscosity of the erupting sediment slurries and may represent a sequential morphology, which is altered by shifts in venting position over

  10. GRAIN SIZE DISTRIBUTION OF SEDIMENT IN THE NORTHERN EAST CHINA SEA AND THE RELATIONSHIP WITH THE SEA CURRENTS

    Institute of Scientific and Technical Information of China (English)

    LEI Kun; YANG Zuosheng; GUO Zhigang

    2002-01-01

    This paper discusses the relationship between the grain size distribution of sediment and currents in the northern East China Sea on the basis of the grain size analysis. The results show that grain size distribution of suspended sediment is controlled by the currents. Suspended sediment in the littoral water is finer than those in the open sea currents. Grain size distribution of surface sediment is affected by the sea currents to some extent. And the grain size of suspended sediment and surface sediment do not agree with each other in positions.

  11. Transition of Quaternary glacial cyclicity in deep-sea records at Nansha, the South China Sea

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    High-resolution oxygen isotope records over the last 2249 ka (MIS 1-86) have been obtained from cores of the upper section (105.08 m) at ODP Site 1143 (water depth of 2772 m)drilled in the Nansha area, southern South China Sea. The sampling resolution is at about 2 ka intervals, resulting in one of the best oxygen isotope records over the global ocean. The oxygen isotope curves, displaying details in the Pleistocene glacial cycles, have revealed a nearly 300 ka long stage of transition from a predominant 40 ka to 100 ka periodicity. Therefore, the "Mid-Pleistocene Revolution" should be considered as a process of transition rather than an abrupt change. Within the 100 ka glacial cycles, the changes in tropical sea surface water were found to lead those in high-latitude ice sheet. Our comparisons show that the ice sheet expansion and the glacial stage extension in the Northern Hemisphere with the 100 ka cycles must have been driven not by ice sheet itself, but by processes outside the high latitudes of the Northern Hemisphere.

  12. Impact of two typhoons on the marine environment in the Yellow Sea and East China Sea

    Science.gov (United States)

    Fu, Dongyang; Luan, Hong; Pan, Delu; Zhang, Ying; Wang, Li'an; Liu, Dazhao; Ding, Youzhuan; Li, Xue

    2016-07-01

    This study investigated the effects of two typhoons (Nari and Wipha) on sea surface temperature (SST) and chlorophyll- a (Chl- a) concentration. Typhoons Nari and Wipha passed through the Yellow Sea on September 13, 2007 and the East China Sea (ECS) on September 16, 2007, respectively. The SST and Chl- a data were obtained from the Aqua/Terra MODIS and NOAA18, respectively, and the temperature and salinity in the southeast of the study area were observed in situ from Argo. The average SST within the study area dropped from 26.33°C on September 10 to a minimum of 22.79°C on September 16. Without the usual phenomenon of `right bias', the most striking response of SST was in the middle of the typhoons' tracks, near to coastal waters. Strong cooling of the upper layers of the water column was probably due to increased vertical mixing, discharge from the Changjiang River estuary, and heavy rainfall. During the typhoons, average Chl- a increased by 11.54% within the study area and by 21.69% in the offshore area near to the southeast ECS. From September 1 to 13, average Chl- a was only 0.10 mg/m3 in the offshore waters but it reached a peak of >0.17 mg/m3 on September 18. This large increase in Chl- a concentration in offshore waters might have been triggered by strong vertical mixing, upwelling induced by strong typhoons, and sedimentation and nutrient influx following heavy rainfall.

  13. Variability of sea surface height in the South China Sea and its relationship to Pacific oscillations

    Institute of Scientific and Technical Information of China (English)

    PEI Yuhua; ZHANG Rong-Hua; ZHANG Xiangming; JIANG Lianghong; WEI Yanzhou

    2015-01-01

    The spatio-temporal variability modes of the sea surface height in the South China Sea (SCS-SSH) are obtained using the Cyclostationary Empirical Orthogonal Function (CSEOF) method, and their relationships to the Pacific basin scale oscillations are examined. The first CSEOF mode of the SCS-SSH is a strongly phase-locked annual cycle that is modulated by a slowly varying principal component (PC); the strength of this annual cycle becomes reduced during El Niño events (at largest by 30% off in 1997/98) and enhanced during La Niña events. The second mode is a low frequency oscillation nearly on decadal time scale, with its spatial structure exhibiting an obscure month-dependence; the corresponding PC is highly correlated with the Pacific Decadal Oscillation (PDO) index. Five independent oscillations in the Pacific are isolated by using the independent component (IC) analysis (ICA) method, and their effects on the SCS-SSH are examined. It is revealed that the pure ENSO mode (which resembles the east Pacific ENSO) has little effect on the low frequency variability of the SCS-SSH while the ENSO reddening mode (which resembles the central Pacific ENSO) has clear effect. As the ENSO reddening mode is an important constituent of the PDO, this explains why the PDO is more important than ENSO in modulating the low frequency variability of SCS-SSH. Meridional saddle like oscillation mode, the Kuroshio extension warming mode, and the equatorial cooling mode are also successfully detected by the ICA, but they have little effect on the low frequency variability of the SCS-SSH. Further analyses suggest the Pacific oscillations are probably influencing the variability of the SCS-SSH in ways that are different from that of the sea surface temperature (SST) in the SCS.

  14. In situ study on photosynthetic characteristics of phytoplankton in the Yellow Sea and East China Sea in summer 2013

    Science.gov (United States)

    Li, Junlei; Sun, Xiaoxia; Zheng, Shan

    2016-08-01

    In situ studies on photosynthetic characteristics of phytoplankton were important for the analysis of changes in community structure and for the prediction and control of algal blooms, but such studies of phytoplankton in offshore China were few. In this study, the detailed distribution of photosynthetic characteristics of phytoplankton in the summer of 2013 in the Yellow Sea and East China Sea was measured using Phyto-PAM (Pulse Amplitude Modulation). The phytoplankton community structure and the environmental parameters were also investigated to estimate the relationship between the distribution of the photochemical competence of phytoplankton and ecological factors. The total average Fv/Fm (the potential maximum quantum yield) value of phytoplankton in the Yellow Sea and East China Sea in summer 2013 was less than 0.5, reflecting that the photosynthetic activity of phytoplankton was relatively low. Fv/Fm of phytoplankton in summer was significantly positively associated with nitrate content (NO2-), which reflects relationship between metabolism and photosynthesis of phytoplankton: accompanied by NO2- metabolism, photosynthesis and photosynthetic capacity may be enhanced simultaneously, so the Fv/Fm value would increase with the NO2- released by phytoplankton. Through the in situ study on photosynthetic characteristics of phytoplankton in the Yellow Sea and East China Sea, we come to the conclusion that photosynthetic characteristics and activity of phytoplankton are influenced by its biological characteristics and surrounding ecological factors, such as irradiance, nutrients and phytoplankton community. Meanwhile, the thermally stratified structure and the movement of water masses, such as the Yangtze River diluted water, the Yellow Sea cold water mass and other different water system, also have an important impact on phytoplankton photosynthetic activity and characteristics. Greater understanding of the detailed photosynthetic characteristics of phytoplankton

  15. Some Results from SAR and Optical Sensor Monitoring of China Seas

    Science.gov (United States)

    Yang, Jingsong; Lou, Xiulin; Chen, Peng; Wang, Juan; Ren, Lin; Chang, Junfang; Pan, Yufang

    2013-01-01

    As part of the final results of Dragon 2 Project Id. 5316 “Demonstrating SAR and optical sensor monitoring of Chinese Seas”, some results from SAR and optical sensor monitoring of China Seas including sea surface winds, ocean surface waves, typhoon and typhoon waves, ocean internal waves, red tides, and ships are given in this paper.

  16. Carbon budget in East China Sea in spring

    Energy Technology Data Exchange (ETDEWEB)

    Peng Tsunghung; Wanninkhof, R. [National Oceanic and Atmospheric Administration, Miami, FL (United States). Atlantic Oceanographic and Meteorological Labs.; Hung, Jiajang [NSYSU, Kaohsiung (Taiwan, Province of China); Millero, F.J. [Miami Univ., FL (United States). Dept. of Marine and Atmospheric Chemistry]|[Rosenstiel School of Marine and Atmospheric Sciences

    1999-04-01

    Results of total dissolved inorganic carbon (DIC) and total alkalinity (TA) measurements made in the East China Sea (ECS) during a geochemical expedition of KEEP (Kuroshio Edge Exchange Processes) program in May of 1996 show that ECS is a CO{sub 2} sink during the spring season. The mean difference of fCO{sub 2} (fugacity of CO{sub 2}) between the atmosphere and surface water is calculated to be 28 {mu}atm, and the resulting net CO{sub 2} invasion flux is 2.1 mol m{sup -2} yr{sup -1}, which gives about 0.03 GtC/yr of CO{sub 2} uptake in this continental shelf in spring. This study supports the notion that the shelf regions can be a significant CO{sub 2} sink. The riverine alkalinity, which discharges into ECS, is estimated to be 1,743 {mu}mol kg{sup -1} on the basis of a linear relationship between TA and salinity. The observed salinity-normalized alkalinity in ECS is higher than that in the open sea, and this excess alkalinity is estimated to be 42 {mu}mol kg{sup -1}. With the known rate of the Changjiang discharge, this excess TA gives a mean residence time of 1.2 years for the continental shelf water in the ECS. The DIC in the ECS is also found to be higher than that in the open sea. This excess DIC is estimated to be about 76 {+-} 70 {mu}mol kg{sup -1}, which is equal to a net carbon input to ECS of 3.9 {+-} 3.6 mol m{sup -2} yr{sup -1}. Based on the riverine alkalinity input, the equivalent riverine carbon flux from Changjiang discharge is estimated to be about 1.8 mol m{sup -2} yr{sup -1}. With net CO{sub 2} invasion flux of 2.1 {+-} 2.8 mol m{sup -2} yr{sup -1}, the remaining 0 {+-} 4.6 mol m{sup -2} yr{sup -1} could come from remineralization of organic matter derived from biological pump in the shelf or terrestrial sources. Although this preliminary carbon budget implies that gas exchange and riverine input are the main sources of excess carbon in ECS, the contribution of biological carbon flux can not be ruled out because of the large uncertainty

  17. Investigating Effects of Monsoon Winds on Hydrodynamics in the South China Sea

    Science.gov (United States)

    Chua, V. P.

    2013-12-01

    The South China Sea is a large marginal sea surrounded by land masses and island chains, and characterized by complex bathymetry and irregular coastlines. The circulation in South China Sea is subjected to seasonal and inter-annual variations of tidal and meteorological conditions. The effects of monsoon winds on hydrodynamics is investigated by applying spectral and harmonic analysis on surface elevation and wind data at stations located in the South China Sea. The analysis indicates varying responses to the seasonal monsoon depending on the location of the station. At Kaohsiung (located in northern South China Sea off Taiwan coast), tides from the Pacific Ocean and the southwest monsoon winds are found to be dominant mechanisms. The Kota Kinabalu and Bintulu stations, located to the east of South China Sea off Borneo coast, are influenced by low energy complex winds, and the shallow bottom bathymetry at these locations leads to tidal energy damping compared to other stations. The tidal dynamics at Tioman, located in southern South China Sea off Malaysia coast, are most responsive to the effects of the northeast monsoon. The complexity of our problem together with the limited amount of available data in the region presents a challenging research topic. An unstructured-grid SUNTANS model is employed to perform three-dimensional simulations of the circulation in South China Sea. Skill assessment of the model is performed by comparing model predictions of the surface elevations and currents with observations. The results suggest that the quality of the model prediction is highly dependent on horizontal grid resolution and coastline accuracy. The model may be used in future applications to investigate seasonal and inter-annual variations in hydrodynamics.

  18. Research on the dynamics of the South China Sea opening: Evidence from analogue modeling

    Institute of Scientific and Technical Information of China (English)

    SUN; Zhen; ZHOU; Di; ZHONG; Zhihong; XIA; Bin; QIU; Xuelin; ZENG; Zuoxun

    2006-01-01

    Independent of Indochina extrusion, the South China Sea experienced a process from passive continental rifting to marginal sea drifting. According to the fault patterns in the Beibu Gulf basin and the Pearl River Mouth basin, the continental rifting and early spreading stage from 32 to 26 Ma were controlled by extensional stress field, which shifted clockwise from southeastward to south southeastward. From 24 Ma on, the sea spread in NW-SE direction and ceased spreading at around 15.5 Ma. Integrated geological information with the assumption that the South China Sea developed along a pre-Cenozoic weakness zone, we did analogue experiments on the South China Sea evolution. Experiments revealed that the pre-existing weakness zone goes roughly along the uplift zone between the present Zhu-1 and Zhu-2 depression. The pre-existing weakness zone is composed of three segments trending NNE, roughly EW and NEE, respectively. The early opening of the South China Sea is accompanied with roughly 15° clockwise rotation, while the SE sub-sea basin opened with SE extension. Tinjar fault was the western boundary of the Nansha block (Dangerous Ground),while Lupar fault was the eastern boundary of the Indochina, NW-trending rift belt known as Zengmu basin developed between above two faults due to block divergent of Indochina from Nansha. In the experiment, transtensional flower structures along NW-trending faults are seen, and slight inversion occurs along some NE-dipping faults. The existence of rigid massifs changed the orientations of some faults and rift belt, and also led to deformation concentrate around the massifs. The rifting and drifting of the South China Sea might be caused by slab pull from the proto South China Sea subducting toward Borneo and/or mantle flow caused by India-Asia collision.

  19. Barrier and compensation layers in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    CHEN Xianyao; QIAO Fangli; WANG Qin; WANG Xiuhong; YUAN Yeli

    2008-01-01

    Climatology of the isothermal layer depth (ILD) and the mixed layer depth (MLD) has been produced from in-situ temperature-salinity observations in the East China Sea (ECS) since 1925. The methods applied on the global are used to compute the ILD and the MLD in the ECS with a temperature criterion △T=0.8℃ for the ILD, and a density criterion with a threshold △σθ corre-sponding to fixed △T=0.8℃ for the MLD, respectively. With the derived climatology ILD and MLD, the monthly variations of the barrier layer (BL) and the compensation layer (CL) in the ECS are analyzed. The BL mainly exists in the shallow water re-gion of the ECS during April-June with thickness larger than 15 m. From December to next March, the area along the shelf break from northeast of Taiwan Island to the northeast ECS is characterized by the CL. Two kinds of main temperature - salinity struc-tures of the CL in this area are given.

  20. The South China Sea thermohaline structure and circulation

    Institute of Scientific and Technical Information of China (English)

    Peter C. Chu(朱伯承); Binbing Ma; Yuchun Chen

    2002-01-01

    In this study, we used the Navy' s Master Oceanographic Observation Data Set (MOODS), consisting of 116 019 temperature and 9 617 salinity profiles, during 1968~1984 to investigate the temporal and spatial variabilities of South China Sea thermohaline structures and circulation.For temperature, profiles were binned into 204 monthly data sets from 1968 to 1984 (17 years). For salinity, profiles were binned into 12 climatological monthly data sets due to the data paucity. A twoscale optimal interpolation method was used to establish a three-dimensional monthly-varying gridded data set from MOODS, covering the area of 5°~25°N and 105°~ 125°E and the depth from the surface to 400 m. After the gridded data set had been established, both composite analysis and the Empirical Orthogonal Function (EOF) analysis (for temperature only) were used to identify the major thermohaline fratures including annual mean, monthly anomalies, and interarmual thermal variabilities. The inverted monthly circulation pattern using the P - vector method is also discussed.

  1. Spacebased Observations of the Oceanic Responses to Monsoons in South China Sea and Arabian Sea

    Science.gov (United States)

    Xie, Xiao-Su; Liu, W. Timothy

    2000-01-01

    A large percentage of the world's population and their agrarian economy must endure the vagaries of the monsoons over the tropical oceans between Africa and the Philippines. We know very little about the oceanic responses to changes of the monsoon in the South China Sea (SCS), which is under the influence of the East Asian Monsoon System, and the Arabian Sea (AS), which is dominated by the Indian Monsoon System; oceanic observations are sparse in both regions. Data from spaceborne microwave scatterometers and radiometers have been used to estimate the two major atmospheric forcing, momentum flux and latent heat flux (LHF), which change with the monsoon winds. Spaceborne sensors also observed the surface signatures of the oceanic response: SST and sea level changes (SLC. Sufficient durations of these data have recently become available to allow the meaningful studies of the annual cycles and interannual anomalies. In SCS, the winter monsoon is strong and steady but the summer monsoon is weak and has large intraseasonal fluctuations. In AS, the summer monsoon is much stronger than the winter monsoon. Significant correlations between LHF and SST tendency, and between curl of wind stress and SLC are found in both oceans. In the north SCS, winds are strong and dry, LHF is high, and ocean cooling is also large in fall; LHF is low and the ocean warms up in spring. In AS, LHF and SST tendency have a semi annual period; LHF is high in summer when the wind is strong and in winter when the wind is dry. Along the coast of Oman, the strong summer southwest monsoon causes intense upwelling, low SST and LHF in summer; such wind-driven SST changes is not as obvious along the Vietnam coast because of the weaker summer monsoon. The negative correlation between curl of wind stress and SLC found in the central basins of both SCS and AS agrees with a simple Ekman pumping scenario. Cyclonic winds drive surface divergence and upwelling in the ocean; the rise of the thermocline causes

  2. The past and the future of zooplankton diversity studies in China seas

    OpenAIRE

    Zhaoli Xu

    2011-01-01

    China has among the largest latitudinal ranges of any country on Earth. Environmental factors such as diverse climate, hydrology and topography jointly determine levels of marine environmental diversityand therefore patterns in zooplankton diversity in China seas. Studies of zooplankton diversity in China progressed through different stages from a main focus on species taxonomy, diversity of distribution pattern, to a focus on environment influences on the ecological group, and finally a focu...

  3. Vertical characteristics revealed by biweekly and synoptic variability of upper sea temperature in the northern South China Sea

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yani; ZHOU Faxiu; HUANG Fei

    2005-01-01

    On the basis of the analysis of the sea temperature data that are observed from the three automatic temperature line acquisition sysem mooring buoys deployed in the central South China Sea (SCS) during South China Sea monsoon experiment, vertical features of biweekly and synoptic variability are discussed. There are five vertical modes, that is, subsurface temperature variability is in phase with,out of phase with, leads to, lags the surface temperature variability, and at depths within the subsurface layer the upper and lower temperature variations are out of phase. The formation of these vertical modes is related to the property of low-level atmospheric forcing and to the background in atmosphere and ocean. Wind stress curl is the main driving factor in forming Modes 1 and 3, and wind stresses in forming Modes 2 and 4.

  4. What depth should deep-sea water be pumped up from in the South China Sea for medicinal research?

    Science.gov (United States)

    He, Shan; Liu, Hongbing; Yang, Xue; Li, Chunxia; Guan, Huashi

    2013-03-01

    In this study, seawater was pumped up from 150, 200, 300, 500 and 1000 m in the South China Sea and analyzed to make certain what depth should deep-sea water (DSW) be pumped up for medicinal usage. The pumping depth of DSW was determined on the basis of chemical ingredients. The analyses of inorganic elements and dissolved organic matter (DOM) were performed by inductively coupled plasma mass spectrometry (ICP-MS) and ultra performance liquid chromatography-mass spectrometry (UPLC-MS) respectively. The raw data were used for hierarchical cluster analysis (HCA) and principal component analysis (PCA). The results showed that seawater pumped up from 500 m and 1000 m was similar in their chemical ingredients, and was different from the seawater pumped up from other depths. These results indicated that seawater from more than 500 m depth had relatively stable chemical ingredients and could be used as DSW in the South China Sea.

  5. Characters of the PCO2 and CO2 Flux in the East China Sea in Autumn

    Institute of Scientific and Technical Information of China (English)

    纪雷; 崔鹤; 辛淑平; 王军; 张龙军; 陆贤昆

    2003-01-01

    PCO2 of air and seawater samples from the East China Sea (ECS) were measured in situ in autumn, 1994. Ocean currents, terrestrial fluviation, biological activities, etc., P CO2 characters in air and seawater were investigated. CO2 flux and its character in the East China Sea are discussed on the basis of the P CO2 profiles of air and seawater. It was clear that the nearshore was the source of CO2; and that the outer sea area was the sink of CO2; and that the shelf area of the ECS is a net sink for atmospheric CO2 in autumn.

  6. ESTIMATION OF SOUNDING ABILITY OF A BRILLOUIN LIDAR IN THE EAST CHINA SEA

    Institute of Scientific and Technical Information of China (English)

    吴东; 宋小全; 刘智深

    2001-01-01

    Vertical profiles of sound speed in the sea can be measured by using laser excited Brillouin scattering. In this paper the dependence of the accuracy of sound speed measurement on the accuracy of the Brillouin shift measurement is analyzed. We calculated the maximum detecting depths of sound speed to an accuracy of 1 m/s by lidar with different laser pulse energy, platform altitude, telescope aperture and lidar effective attenuation coefficient. The estimation of sounding ability in the East China Sea is made in some stations. These data can be used in the design of Brillouin Lidar for the China Sea.

  7. Crustal structure across the Xisha Trough, northwestern South China Sea

    Science.gov (United States)

    Qiu, Xuelin; Ye, Sanyu; Wu, Shimin; Shi, Xiaobin; Zhou, Di; Xia, Kanyuan; Flueh, Ernst R.

    2001-11-01

    Located at the northwestern part of the South China Sea (SCS) between the Hainan and Xisha (Paracel) Islands, the Xisha Trough represents a failed rift in conjunction with the opening of the SCS between 32 and 17 Ma. From west towards east within a scale of several hundred kilometers, it presents all major stages of the rifting process, and thus, provides an ideal place to study the rifting process in great details. In the autumn of 1996, a joint team of Sino-German scientists carried out a wide-angle seismic experiment across the Xisha Trough with 10 ocean bottom hydrophones (OBH) along a 237-km NNW-SSE-oriented profile, which was surveyed in 1987 with multi-channel seismic (MCS) method by BGR of Germany and SOA of China. Favorable weather conditions and the powerful 4×12-l air gun array rendered very good quality data with seismic signals observed at the offset of up to 110 km. A detailed velocity-depth model was obtained by using an interactive trial-and-error 2D ray-tracing method. Interpretation of the MCS data published by BGR provides very good geometrical constraints of the complex upper crustal structure, which is characterized by fault blocks, half-horsts and half-grabens filled with syn- and post-rift Cenozoic sediments. The velocity model in turn confirms the major structure outlined by the interpretation of the MCS data, showing a varying sedimentary layer between 1 and 4 km of thickness and velocities between 1.7 and 4.5 km/s. The P-wave velocity of 5.5 km/s on the top of the crystalline basement is relatively low, suggesting strong weathering. Within the crystalline crust, the velocity increases downward continuously to 6.8 km/s at the bottom of the crust without a clear differentiation in the middle crust, showing clearly its continental nature even beneath the Xisha Trough. The Moho is marked by a sharp first-order interface with a velocity of 8.0-8.1 km/s at the uppermost mantle. The Moho depth is 15 km beneath the center of the trough and

  8. Geopolitical Implications of the Sino-Japanese East China Sea Dispute for the U.S.

    OpenAIRE

    Chapman, Bert

    2016-01-01

    Much analysis on Asian strategic challenges facing the U.S. has justifiably emphasized the South China Sea (SCS). This has also been reflected in 2016 presidential campaign debate on the SCS as an emerging area of U.S. foreign and national security policy concern. The East China Sea (ECS) is at least as important for the strategic interests of the U.S. and its allies given the tension between China and Japan over the Senkaku/Diaoyu islands, potential energy resources in this body of water, in...

  9. Preliminary Design of Offshore Wind Turbine Tension Leg Platform In the South China Sea

    OpenAIRE

    Hai-feng Wang; You-hua Fan

    2013-01-01

    China has the richest offshore wind resource in the world. Much of undeveloped resource should consider floating tension leg platform (TLP) wind turbine because of its advantage and potential in cost and safety for deep sea, but the related research is short in China. In this thesis we assess a preliminary design for a type of TLP structure in the South China Sea (SCS-TLP) closed to Guangdong province basing on NREL 5MW wind turbine. By coupled analysis in the time domain, the pla...

  10. The barrier layer in the southern region of the South China Sea

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    By analysing the CTD data in the southernregion of the South China Sea gathered during six cruises between 1989 and 1999, a barrier layer with seasonal variation just like what exists in the equatorial oceans is found in this region. It is the first discovery in such a marginal sea yet.It is strong in autunm and a little weak in summer and winter. The thicker the barrier layer, the higher the average temperature of the upper mixed layer. The region with the thicker barrier layer overlaps the region with the higher average temperature of the upper mixed layer, and accords with the thicker region of the warm pool in the South China Sea got from the Levitus data. The barrier layer in the southern region of the South China Sea has significant influence on the heat storage of the upper ocean there.``

  11. Physical and underway data collected aboard the MELVILLE during cruise MGLN32MV in the Philippine Sea, South China Sea (Nan Hai) and Sulu Sea from 2008-02-07 to 2008-02-28 (NCEI Accession 0155954)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0155954 includes physical and underway data collected aboard the MELVILLE during cruise MGLN32MV in the Philippine Sea, South China Sea (Nan Hai) and...

  12. Physical and underway data collected aboard the MELVILLE during cruise MGLN30MV in the Philippine Sea, South China Sea (Nan Hai) and Sulu Sea from 2007-11-30 to 2008-01-04 (NODC Accession 0098586)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0098586 includes physical and underway data collected aboard the MELVILLE during cruise MGLN30MV in the Philippine Sea, South China Sea (Nan Hai) and...

  13. Chemical, optical and other data collected aboard the MELVILLE during cruise MV0902 in the Philippine Sea, South China Sea (Nan Hai) and Sulu Sea from 2009-02-06 to 2009-02-23 (NODC Accession 0116957)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0116957 includes chemical, optical and other data collected aboard the MELVILLE during cruise MV0902 in the Philippine Sea, South China Sea (Nan Hai)...

  14. Hydrodynamic condition and suspended sediment diffusion in the Yellow Sea and East China Sea

    Science.gov (United States)

    Li, Guangxue; Qiao, Lulu; Dong, Ping; Ma, Yanyan; Xu, Jishang; Liu, Shidong; Liu, Yong; Li, Jianchao; Li, Pin; Ding, Dong; Wang, Nan; Olusegun A, Dada; Liu, Ling

    2016-08-01

    Based on monthly averaged current, temperature, and salinity, we analyzed the changes of suspended sediment concentration (SSC) and the relationship with the warm current, coastal current, and cold water mass (CWM) in the East China Seas (ECSs). The result shows that the coastal current and surface diluted water are the route for transporting suspended sediment. The Kuroshio and its derived warm current branches play the important role of the continental shelf circulation system and control the diffusion of suspended sediment. High SSC has been mainly concentrated in coastal current and CWM. Two sedimentary dynamic patterns have been identified. The winter-half-year pattern lasts almost 7 months. The coastal currents off the Shandong Peninsula, northern Jiangsu, Zhejiang-Fujian coast are the main routes for diffusion and deposition of the suspended sediment from the Yellow River and Changjiang River. The summer-half-year pattern is characterized by the well-developed CWM. All CWMs have a unique function to trap suspended sediment under the thermocline due to weakening tidal current and residual current there. These CWMs in the Yellow Sea (YS) and north ECS are connected together. The layer above the thermocline is characterized by diluted water with low salinity, high temperature. Suspended sediment can be transported into the Okinawa Trough and the South Korea coast during this period. A strong eddy always occur nearby the Kuroshio bend at northeast Taiwan, which has promoted the exchange between the ECS shelf and Okinawa Trough, and the development of the shelf edge current and Taiwan warm current (TWC).

  15. Middle Holocene warm period and sea level high in coastal areas,North China

    Institute of Scientific and Technical Information of China (English)

    MENG Guanglan; HAN Yousong; WANG Shaoqing

    2005-01-01

    Relevant geological, geographical, archaeological data were collected to study the characteristics of middle Holocene warm period and sea level high on North China coast. Middle Holocene climate and sea level change on North China coast were correlated to warm marine environment events in about 8-3 ka B.P. The sea level in about 8 ka B.P. was higher than present mean sea level, then fluctuated for 5 000 years and after that it became even in 3 ka B.P. The highest sea level occurred in about 6-5 ka B.P.; the maximum was about 2-3 m and minimum was about 1-2 m.

  16. Assessment of satellite ocean color products of MERIS, MODIS and SeaWiFS along the East China Coast (in the Yellow Sea and East China Sea)

    Science.gov (United States)

    Cui, Tingwei; Zhang, Jie; Tang, Junwu; Sathyendranath, Shubha; Groom, Steve; Ma, Yi; Zhao, Wei; Song, Qingjun

    2014-01-01

    The validation of satellite ocean-color products is an important task of ocean-color missions. The uncertainties of these products are poorly quantified in the Yellow Sea (YS) and East China Sea (ECS), which are well known for their optical complexity and turbidity in terms of both oceanic and atmospheric optical properties. The objective of this paper is to evaluate the primary ocean-color products from three major ocean-color satellites, namely the Moderate Resolution Imaging Spectroradiometer (MODIS), Medium Resolution Imaging Spectrometer (MERIS), and Sea-viewing Wide Field-of-view Sensor (SeaWiFS). Through match-up analysis with in situ data, it is found that satellite retrievals of the spectral remote sensing reflectance Rrs(λ) at the blue-green and green bands from MERIS, MODIS and SeaWiFS have the lowest uncertainties with a median of the absolute percentage of difference (APDm) of 15-27% and root-mean-square-error (RMS) of 0.0021-0.0039 sr-1, whereas the Rrs(λ) uncertainty at 412 nm is the highest (APDm 47-62%, RMS 0.0027-0.0041 sr-1). The uncertainties of the aerosol optical thickness (AOT) τa, diffuse attenuation coefficient for downward irradiance at 490 nm Kd(490), concentrations of suspended particulate sediment concentration (SPM) and Chlorophyll a (Chl-a) were also quantified. It is demonstrated that with appropriate in-water algorithms specifically developed for turbid waters rather than the standard ones adopted in the operational satellite data processing chain, the uncertainties of satellite-derived properties of Kd(490), SPM, and Chl-a may decrease significantly to the level of 20-30%, which is true for the majority of the study area. This validation activity advocates for (1) the improvement of the atmosphere correction algorithms with the regional aerosol optical model, (2) switching to regional in-water algorithms over turbid coastal waters, and (3) continuous support of the dedicated in situ data collection effort for the validation task.

  17. Air-sea exchange of gaseous mercury in the East China Sea.

    Science.gov (United States)

    Wang, Chunjie; Ci, Zhijia; Wang, Zhangwei; Zhang, Xiaoshan

    2016-05-01

    Two oceanographic cruises were carried out in the East China Sea (ECS) during the summer and fall of 2013. The main objectives of this study are to identify the spatial-temporal distributions of gaseous elemental mercury (GEM) in air and dissolved gaseous mercury (DGM) in surface seawater, and then to estimate the Hg(0) flux. The GEM concentration was lower in summer (1.61 ± 0.32 ng m(-3)) than in fall (2.20 ± 0.58 ng m(-3)). The back-trajectory analysis revealed that the air masses with high GEM levels during fall largely originated from the land, while the air masses with low GEM levels during summer primarily originated from ocean. The spatial distribution patterns of total Hg (THg), fluorescence, and turbidity were consistent with the pattern of DGM with high levels in the nearshore area and low levels in the open sea. Additionally, the levels of percentage of DGM to THg (%DGM) were higher in the open sea than in the nearshore area, which was consistent with the previous studies. The THg concentration in fall was higher (1.47 ± 0.51 ng l(-1)) than those of other open oceans. The DGM concentration (60.1 ± 17.6 pg l(-1)) and Hg(0) flux (4.6 ± 3.6 ng m(-2) h(-1)) in summer were higher than those in fall (DGM: 49.6 ± 12.5 pg l(-1) and Hg(0) flux: 3.6 ± 2.8 ng m(-2) h(-1)). The emission flux of Hg(0) from the ECS was estimated to be 27.6 tons yr(-1), accounting for ∼0.98% of the global Hg oceanic evasion though the ECS only accounts for ∼0.21% of global ocean area, indicating that the ECS plays an important role in the oceanic Hg cycle. PMID:26975003

  18. Sea surface temperature record from the north of the East China Sea since late Holocene

    Institute of Scientific and Technical Information of China (English)

    LI GuangXue; SUN XiaoYan; LIU Yong; BICKERT Torsten; MA YanYan

    2009-01-01

    Using the alkenone paleotemperature index U_(37)~(k'), a high-resolution sea surface temperature (SST) record since 3600 a BP was reconstructed from the mud area in the north of the East China Sea. Com-bining with the grain size distribution curve of sensitive grain size group, which may reflect the East Asia Winter Monsoon activity, the palaeoenvironmental evolution cycle throughout the late Holocene in the area was obtained. The marine environment evolution during the last 3600 years displays a five-stage trend. (1) Temperature descending period from 0.85 cal. ka BP to present. The maximum temperature decrease amplitude is 213. The winter monsoon intensified and 'Little Ice Age' were recorded in this period. (2) Warming period from 1.90 to 0.85 cal. ka BP. The mean temperature increase amplitude is 0.8℃. The Sui-Tang warming period was recorded at about 0.85-1.35 cal. ka BP and a prominent cooling event was recorded at 1.4 cal. ka BP in this period. (3) Temperature descending period from 2.55 to 1.90 cal. ka BP. Temperature cooling amplitude is 0.9℃. This period is coincident with an integrated temperature circle recorded in the Antarctic ice core, with the temperature changes from a slow cooling stage to a rapid warming stage. (4) Temperature comparatively stable with a little as-cending period from 3.2 to 2.55 cal. ka BP. Temperature warming amplitude is 0.3℃. This period is coincident with the temperature fluctuant ascending period recorded in Antarctic ice core. (5) Temper-ature comparatively stable with little descending period from 3.6 to 3.2 cal. ka BP. This period corres-ponds with the temperature fluctuant cooling period recorded in Antarctic ice core. Basically, those five periods were coincident with the Antarctic ice core record. During the global cooling stage, the SST change in the continental shelf sea can be adjusted simultaneously.

  19. Maritime Territorialisation as Performance of Sovereignty and Nationhood in the South China Sea

    DEFF Research Database (Denmark)

    Roszko, Edyta

    2015-01-01

    The South China Sea (SCS) is a conflict-ridden international arena of rivalry between China, the US, India, and the other ASEAN countries over sovereignty, resources and security. In this geo-political clash China is the dominant force and Vietnam its main challenger. While most analysts assume...... that the various claims to the mostly uninhabited islands are motivated by the presence of submarine mineral resources, the conflicts evoke strong nationalist feelings in Vietnam and China, fuelled by narratives of the historical presence of fisheries and navies. By analyzing the tension between complex...... is a paradox of treating the sea as ‘land’ produced by the performance of a socially constructed image of the state geo-body capitalizing on strong nationalistic sentiments in China and Vietnam....

  20. Modelling sea level data from China and Malay-Thailand to estimate Holocene ice-volume equivalent sea level change

    Science.gov (United States)

    Bradley, Sarah L.; Milne, Glenn A.; Horton, Benjamin P.; Zong, Yongqiang

    2016-04-01

    This study presents a new model of Holocene ice-volume equivalent sea level (ESL), extending a previously published global ice sheet model (Bassett et al., 2005), which was unconstrained from 10 kyr BP to present. This new model was developed by comparing relative sea level (RSL) predictions from a glacial isostatic adjustment (GIA) model to a suite of Holocene sea level index points from China and Malay-Thailand. Three consistent data-model misfits were found using the Bassett et al. (2005) model: an over-prediction in the height of maximum sea level, the timing of this maximum, and the temporal variation of sea level from the time of the highstand to present. The data-model misfits were examined for a large suite of ESL scenarios and a range of earth model parameters to determine an optimum model of Holocene ESL. This model is characterised by a slowdown in melting at ∼7 kyr BP, associated with the final deglaciation of the Laurentide Ice Sheet, followed by a continued rise in ESL until ∼1 kyr BP of ∼5.8 m associated with melting from the Antarctic Ice Sheet. It was not possible to identify an earth viscosity model that provided good fits for both regions; with the China data preferring viscosity values in the upper mantle of less than 1.5 × 1020 Pa s and the Malay-Thailand data preferring greater values. We suggest that this inference of a very weak upper mantle for the China data originates from the nearby subduction zone and Hainan Plume. The low viscosity values may also account for the lack of a well-defined highstand at the China sites.

  1. Deepwater Ventilation and Stratification in the Neogene South China Sea

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Combined data of physical property, benthic foraminifera, and stable isotopes from ODP Sites 1148, 1146, and 1143 are used to discuss deep water evolution in the South China Sea (SCS) since the Early Miocene. The results indicate that 3 lithostratigraphic units, respectively corresponding to 21-17 Ma, 15-10 Ma, and 10-5 Ma with positive red parameter (a*) marking the red brown sediment color represent 3 periods of deep water ventilation. The first 2 periods show a closer link to contemporary production of the Antarctic Bottom Water (AABW) and Northern Component Water(NCW), indicating a free connection of deep waters between the SCS and the open ocean before 10 Ma.After 10 Ma, red parameter dropped but stayed higher than the modern value (a*=0), the CaCO3 percentage difference between Site 1148 from a lower deepwater setting and Site 1146 from an upper deepwater setting enlarged significantly, and benthic species which prefer oxygen-rich bottom conditions dramatically decreased. Coupled with a major negative excursion of benthic δ13C at ~10 Ma,these parameters may denote a weakening in the control of the SCS deep water by the open ocean.Probably they mark the birth of a local deep water due to shallow waterways or rise of sill depths during the course of sea basin closing from south to east by the west-moving Philippine Arc after the end of SCS seafloor spreading at 16-15 Ma. However, it took another 5 Ma before the dissolved oxygen approached close to the modern level. Although the oxygen level continued to stabilize, several Pacific Bottom Water (PBW) and Pacific Deep Water (PDW) marker species rapidly increased since ~6 Ma,followed by a dramatic escalation in planktonic fragmentation which indicates high dissolution especially after ~5 Ma. The period of 5-3 Ma saw the strongest stratified deepwater in the then SCS, as indicated by up to 40% CaCO3 difference between Sites 1148 and 1146. Apart from a strengthening PDW as a result of global cooling and ice

  2. Size distributions and source function of sea spray aerosol over the South China Sea

    Science.gov (United States)

    Chu, Yingjia; Sheng, Lifang; Liu, Qian; Zhao, Dongliang; Jia, Nan; Kong, Yawen

    2016-08-01

    The number concentrations in the radius range of 0.06-5 μm of aerosol particles and meteorological parameters were measured on board during a cruise in the South China Sea from August 25 to October 12, 2012. Effective fluxes in the reference height of 10 m were estimated by steady state dry deposition method based on the observed data, and the influences of different air masses on flux were discussed in this paper. The number size distribution was characterized by a bimodal mode, with the average total number concentration of (1.50 ± 0.76)×103 cm-3. The two mode radii were 0.099 µm and 0.886 µm, both of which were within the scope of accumulation mode. A typical daily average size distribution was compared with that measured in the Bay of Bengal. In the whole radius range, the number concentrations were in agreement with each other; the modes were more distinct in this study than that abtained in the Bay of Bengal. The size distribution of the fluxes was fitted with the sum of log-normal and power-law distribution. The impact of different air masses was mainly on flux magnitude, rather than the shape of spectral distribution. A semiempirical source function that is applicable in the radius range of 0.06 µm< r 80<0.3 µm with the wind speed varying from 1.00 m s-1 to 10.00 m s-1 was derived.

  3. A Preliminary Study of the Microbial Resources and Their Biological Activities of the East China Sea

    Directory of Open Access Journals (Sweden)

    Xiaoling Lu

    2011-01-01

    Full Text Available East China Sea is one of the four sea areas in China, which possesses peculiar ecological environment and many kinds of living creatures, especially the microorganisms. We established the East China Sea microorganism library (during 2006–2010 for the first time, which stored about 30000 strains that covered most kinds of the species. In this paper, 395 pure strains of East China Sea microorganism library which belong to 33 different genera were mainly introduced. Sulfitobacter, Halomonas, Bacillus, Pseudoalteromonas, and Idiomarina were the most dominant species. On the large-scale biological activity screening of the 395 strains, 100 strains possess different biological activities based on different screening models, of which 11.4% strains have antibacterial activities, 15.9% have cytotoxicity activities, and 6.1% have antioxidation activities. Besides, the secondary metabolites of 6 strains with strong biological activities were studied systematically; diketopiperazines and macrocyclic lactones are the active secondary metabolites. The species and the biological activity of microorganisms diversity, the abundant structure type of the secondary metabolites, and their bioactivities all indicate that East China Sea is a potent marine microorganisms-derived developing resource for drug discovery.

  4. Reconstruction of paleocoastlines for the northwestern South China Sea since the Last Glacial Maximum

    Institute of Scientific and Technical Information of China (English)

    HARFF; Jan; MEYER; Michael

    2009-01-01

    The range of relative sea level rise in the northwestern South China Sea since the Last Glacial Maximum was over 100 m. As a result, lowland regions including the Northeast Vietnam coast, Beibu Gulf, and South China coast experienced an evolution from land to sea. Based on the principle of reconstructing paleogeography and using recent digital elevation model, relative sea level curves, and sediment accumulation data, this paper presents a series of paleogeographic scenarios back to 20 cal. ka BP for the northwestern South China Sea. The scenarios demonstrate the entire process of coastline changes for the area of interest. During the late glacial period from 20 to 15 cal. ka BP, coastline slowly retreated, causing a land loss of only 1×104 km2, and thus the land-sea distribution remained nearly unchanged. Later in 15-10 cal. ka BP coastline rapidly retreated and area of land loss was up to 24×104 km2, causing lowlands around Northeast Vietnam and South China soon to be underwater. Coastline retreat continued quite rapidly during the early Holocene. From 10 to 6 cal. ka BP land area had decreased by 9×104 km2, and during that process the Qiongzhou Strait completely opened up. Since the mid Holocene, main controls on coastline change are from vertical crustal movements and sedimentation. Transgression was surpassed by regression, resulting in a land accretion of about 10×104 km2.

  5. Reconstruction of paleocoastlines for the northwestern South China Sea since the Last Glacial Maximum

    Institute of Scientific and Technical Information of China (English)

    YAO YanTao; HARFF Jan; MEYER Michael; ZHAN WenHuan

    2009-01-01

    The range of relative sea level rise in the northwestern South China Sea since the Last Glacial Maximum was over 100 m. As a result, lowland regions including the Northeast Vietnam coast, Beibu Gulf, and South China coast experienced an evolution from land to sea. Based on the principle of recon structing paleogeography and using recent digital elevation model, relative sea level curves, and sediment accumulation data, this paper presents a series of paleogeographic scenarios back to 20 cal. ka BP for the northwestern South China Sea. The scenarios demonstrate the entire process of coastline changes for the area of interest. During the late glacial period from 20 to 15 cal. ka BP, coastline slowly retreated, causing a land loss of only 1 ×104 km2, and thus the land-sea distribution remained nearly unchanged. Later in 15--10 cal. ka BP coastline rapidly retreated and area of land loss was up to 24×104 km2, causing lowlands around Northeast Vietnam and South China soon to be underwater. Coastline retreat continued quite rapidly during the early Holocene. From 10 to 6 cal. ka BP land area had decreased by 9×104 km2, and during that process the Qiongzhou Strait completely opened up. Since the mid Holocene, main controls on coastline change are from vertical crustal movements and sedimentation. Transgression was surpassed by regression, resulting in a land accretion of about 10×104 km2.

  6. Comparison of modern pollen distribution between northern and southern South China Sea

    Science.gov (United States)

    Luo, C.; Chen, M.; Xiang, R.; Liu, J.; Zhang, L.; Lu, J.

    2013-12-01

    To understand pollen transport mechanic and terrigenous area is the base to explain pollen data correctly in Southern South China Sea (Fig.1). Based on Palynology analyzing the following preliminary conclusions are listed. 1. Air pollen differences between northern and southern South China Sea 15 air pollen samples were collected from northern part of the South China Sea from August to September 2011. 13 air pollen samples were collected from southern South China Sea in December 2011. It was found that the air pollen are different between northern and southern part of South China Sea: the pollen types in the north are more abundant than in the south, Ulmaceae, Monolete spore, Cyperaceae, Euphorbiaceae, Rubiaceae, Artemisia, Chenopodiaceae, Rosaceae, Labiatae occur only in the north, they do not occur or is just sporadic in the south. The total pollen number and concentration in the north is 10 times of the south, one of the reasons may be that the sampling season in the north is autumn with more flowering plants, the sampling season in the south is winter, with fewer flowering plants; the second reason might be that pollen and spore in autumn and winter are mainly spread by the winter wind, thus they reduce from north to south. 2. Pollen differences of the surface sediments between northern and southern South China Sea 14 samples were collected from surface sediments in the northern part of the South China Sea from August to October, 2011. 12 samples were collected from surface sediments in the southern part of the South China Sea from year 1997 to 2002. The differences of pollen characteristics from the surface sediments between northern and southern part of South China Sea are: pollen types and quantities in the north are richer than in south. There are Trilete spores (35-100%), Pinus (3-65%) in northern of SCS, with pollen concentration of 33-1031grain/g. There are only a small amount of Trilete-spore and Pinus pollen in southern of SCS. Pollen concentration in

  7. Assessment of marine debris in beaches or seawaters around the China Seas and coastal provinces.

    Science.gov (United States)

    Zhou, Changchun; Liu, Xu; Wang, Zhengwen; Yang, Tiantian; Shi, Linna; Wang, Linlin; You, Suwen; Li, Min; Zhang, Cuicui

    2016-02-01

    Compared with United States of America (USA), Brazil, Chile, Australia, limited attention has been paid to marine debris research in China and few studies have attempted to quantify the abundance and mass of marine debris. In this study, firstly the general status and sources of marine debris in China were assessed in the time period between 2007 and 2014, and secondly marine debris situation was evaluated in three China Sea Areas (the North China Sea, the East China Sea and the South China Sea) from 2009 to 2013, and finally marine debris conditions and sources were analyzed in beaches or seawaters around some coastal provinces of China during 2007-2013. Based on above analysis, the primary conclusions were as follows: (1) The mean number and weight densities of beached marine debris (BMD) and submerged marine debris (SMD) were 4.30, 0.13items/100m(2) and 133.80, 22.60g/100m(2) in China from 2007 to 2014, respectively. The average number density of the large size FMD (LOSFMD) was 0.0024items/100m(2) and that of the small and medium size FMD (SMSFMD) was 0.30items/100m(2), and the mean weight density of the SMSFMD was 1.40g/100m(2) from 2008 to 2014. The SMD and FMD densities were at the low level and the BMD density was at the high level in China. (2) The marine debris primarily was comprised of plastic, Styrofoam, wood, glass, rubber, fabric/fiber and metal, which included almost all major categories of marine debris. (3) Sources of BMD and FMD were as follows: the first source was coastal/recreational activities, followed by other disposal sources, navigation/fishing activities and the activities related smoking, and the least source being those associated with medical/sanitary activities, while the source of SMD remained unknown. (4) The mean number and weight densities of BMD were the biggest in the North China Sea, while those of FMD and SMD were the highest in the northern South China Sea. The results of this study were beneficial to the establishment of

  8. Exploitable wave energy assessment based on ERA-Interim reanalysis data-A case study in the East China Sea and the South China Sea

    Institute of Scientific and Technical Information of China (English)

    WAN Yong; ZHANG Jie; MENG Junmin; WANG Jing

    2015-01-01

    Wave energy resources assessment is a very important process before the exploitation and utilization of the wave energy. At present, the existing wave energy assessment is focused on theoretical wave energy conditions for interesting areas. While the evaluation for exploitable wave energy conditions is scarcely ever performed. Generally speaking, the wave energy are non-exploitable under a high sea state and a lower sea state which must be ignored when assessing wave energy. Aiming at this situation, a case study of the East China Sea and the South China Sea is performed. First, a division basis between the theoretical wave energy and the exploitable wave energy is studied. Next, based on recent 20 a ERA-Interim wave field data, some indexes including the spatial and temporal distribution of wave power density, a wave energy exploitable ratio, a wave energy level, a wave energy stability, a total wave energy density, the seasonal variation of the total wave energy and a high sea condition frequency are calculated. And then the theoretical wave energy and the exploitable wave energy are compared each other;the distributions of the exploitable wave energy are assessed and a regional division for exploitable wave energy resources is carried out;the influence of the high sea state is evaluated. The results show that considering collapsing force of the high sea state and the utilization efficiency for wave energy, it is determined that the energy by wave with a significant wave height being not less 1 m or not greater than 4 m is the exploitable wave energy. Compared with the theoretical wave energy, the average wave power density, energy level, total wave energy density and total wave energy of the exploitable wave energy decrease obviously and the stability enhances somewhat. Pronounced differences between the theoretical wave energy and the exploitable wave energy are present. In the East China Sea and the South China Sea, the areas of an abundant and stable

  9. Analysis of sea use landscape pattern based on GIS: a case study in Huludao, China.

    Science.gov (United States)

    Suo, Anning; Wang, Chen; Zhang, Minghui

    2016-01-01

    This study aims to analyse sea use landscape patterns on a regional scale based on methods of landscape ecology integrated with sea use spatial characteristics. Several landscape-level analysis indices, such as the dominance index, complex index, intensivity index, diversity index and sea congruency index, were established using Geographic Information System (GIS) and applied in Huludao, China. The results indicated that sea use landscape analysis indices, which were created based on the characteristics of sea use spatial patterns using GIS, are suitable to quantitatively describe the landscape patterns of sea use. They are operable tools for the landscape analysis of sea use. The sea use landscape in Huludao was dominated by fishing use with a landscape dominance index of 0.724. The sea use landscape is a complex mosaic with high diversity and plenty of fishing areas, as shown by the landscape complex index of 27.21 and the landscape diversity index of 1.25. Most sea use patches correspond to the marine functional zonation plan and the sea use congruency index is 0.89 in the fishing zone and 0.92 in the transportation zone.

  10. A New model to forecast fishing ground ofScomber japonicus in the Yellow Sea and East China Sea

    Institute of Scientific and Technical Information of China (English)

    GAO Feng; CHEN Xinjun; GUAN Wenjiang; LI Gang

    2016-01-01

    The pelagic species is closely related to the marine environmental factors, and establishment of forecasting model of fishing ground with high accuracy is an important content for pelagic fishery. The chub mackerel (Scomber japonicus) in the Yellow Sea and East China Sea is an important fishing target for Chinese lighting purse seine fishery. Based on the fishery data from China’s mainland large-type lighting purse seine fishery for chub mackerel during the period of 2003 to 2010 and the environmental data including sea surface temperature (SST), gradient of the sea surface temperature (GSST), sea surface height (SSH) and geostrophic velocity (GV), we attempt to establish one new forecasting model of fishing ground based on boosted regression trees. In this study, the fishing areas with fishing effort is considered as one fishing ground, and the areas with no fishing ground are randomly selected from a background field, in which the fishing areas have no records in the logbooks. The performance of the forecasting model of fishing ground is evaluated with the testing data from the actual fishing data in 2011. The results show that the forecasting model of fishing ground has a high prediction performance, and the area under receiver operating curve (AUC) attains 0.897. The predicted fishing grounds are coincided with the actual fishing locations in 2011, and the movement route is also the same as the shift of fishing vessels, which indicates that this forecasting model based on the boosted regression trees can be used to effectively forecast the fishing ground of chub mackerel in the Yellow Sea and East China Sea.

  11. Estimating peak response frequencies in a tidal band in the seas adjacent to China with a numerical model

    Institute of Scientific and Technical Information of China (English)

    CUI Xinmei; FANG Guohong; TENG Fei; WU Di

    2015-01-01

    A numerical method is designed to examine the response properties of real sea areas to open ocean forcing. The application of this method to modeling the China's adjacent seas shows that the Bohai Sea has a highest peak response frequency (PRF) of 1.52 d−1; the northern Yellow Sea has a PRF of 1.69 d−1; the Gyeonggi Bay has a high amplitude gain plateau in the frequency band roughly from 1.7 to 2.7 d−1; the Yellow Sea (includ-ing the Gyeonggi Bay), the East China Sea shelf and the Taiwan Strait have a common high amplitude gain band with frequencies around 1.76 to 1.78 d−1 and are shown to be a system that responds to the open ocean forcing in favor of amplifying the waves with frequencies in this band; the Beibu Gulf, the Gulf of Thailand and the South China Sea deep basin have PRFs of 0.91, 1.01 and 0.98 d−1 respectively. In addition, the East China Sea has a Poincare mode PRF of 3.91 d−1. The PRFs of the Bohai Sea, the northern Yellow Sea, the Bei-bu Gulf and the South China Sea can be explained by a classical quarter (half for the Bohai Sea) wavelength resonance theory. The results show that further investigations are needed for the response dynamics of the Yellow Sea-East China Sea-Taiwan Strait system, the East China Sea Poincare mode, the Taiwan Strait, and the Gulf of Thailand.

  12. Data from renewable energy assessments for resort islands in the South China Sea.

    Science.gov (United States)

    Basir Khan, M Reyasudin; Jidin, Razali; Pasupuleti, Jagadeesh

    2016-03-01

    Renewable energy assessments for resort islands in the South China Sea were conducted that involves the collection and analysis of meteorological and topographic data. The meteorological data was used to assess the PV, wind and hydropower system potentials on the islands. Furthermore, the reconnaissance study for hydro-potentials were conducted through topographic maps in order to determine the potential sites suitable for development of run-of-river hydropower generation. The stream data was collected for 14 islands in the South China Sea with a total of 51 investigated sites. The data from this study are related to the research article "Optimal combination of solar, wind, micro-hydro and diesel systems based on actual seasonal load profiles for a resort island in the South China Sea" published in Energy (Khan et al., 2015) [1].

  13. Measurement of single-fish target strength in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    CHEN Guobao; LI Yongzhen; CHEN Pimao; ZHANG Jun; FANG Lichen; LI Nana

    2012-01-01

    We measured the target strength (TS) of three commercial fish species:whitespotted spinefoot (Siganus canaliculatus),black porgy (Acanthopagrus schlegelii),and creek red bream (Lutjanus argentimaculatus),in the South China Sea.The TS of caged or tethered fish (n=76 total) was measured using a Simrad EY60 portable scientific echosounder at 120 kHz.We evaluated the relationship between TS and total length (TL,cm) for the three species.This is the first attempt to use split-beam acoustics to measure single-fish TS in the South China Sea by Chinese researchers.Our results will improve the accuracy and precision of acoustic abundance estimates of commercially important species and further the development of underwater acoustic survey techniques in fisheries in the South China Sea.

  14. Energy audit data for a resort island in the South China Sea.

    Science.gov (United States)

    Basir Khan, M Reyasudin; Jidin, Razali; Pasupuleti, Jagadeesh

    2016-03-01

    The data consists of actual generation-side auditing including the distribution of loads, seasonal load profiles, and types of loads as well as an analysis of local development planning of a resort island in the South China Sea. The data has been used to propose an optimal combination of hybrid renewable energy systems that able to mitigate the diesel fuel dependency on the island. The resort island selected is Tioman, as it represents the typical energy requirements of many resort islands in the South China Sea. The data presented are related to the research article "Optimal Combination of Solar, Wind, Micro-Hydro and Diesel Systems based on Actual Seasonal Load Profiles for a Resort Island in the South China Sea" [1].

  15. Nitrate dual isotopic composition in the northern South China Sea and neighboring West Philippine Sea

    Science.gov (United States)

    Yang, J.; Xu, M.; Wu, Y.; Dai, M.; Kao, S.

    2013-12-01

    Nitrate nitrogen and oxygen isotopic compositions (δ15NNO3 and δ18ONO3) were used to diagnose nitrate dynamics and the origins of water masses in the northern South China Sea (SCS) and West Philippine Sea (WPS) where water exchanges via the Luzon Strait at different depths. In the SCS, 1-3‰ greater upward increase in δ18ONO3 relative to corresponding δ15NNO3 was just observed in the lower euphotic zone (EZ), indicating a rapid internal cycle of nitrate assimilation and remineralization. Much lower nitrate concentration in the EZ of WPS does not allow us to measure its dual isotopes. From 500 m deep to the base of EZ in the WPS, non-proportional decreases in δ15NNO3 (from 6.4‰ to 2.1-2.6‰) and δ18ONO3 (from 3.0‰ to 1.1‰) accompanying with elevated N:P ratio anomalies (N* from -1.2 μM up to 2 μM), suggest the accumulation of atmospheric-derived N (e.g. N2 fixation and/or N deposition). This allochthonous N signal cumulated in the subsurface of WPS may regulate the δ15NNO3 in the SCS subsurface due to seasonal Kuroshio intrusion, which could supply isotopically light nitrate as newly fixed N source to the SCS. The higher (~0.5‰) δ15NNO3 and δ18ONO3 values, associated with lower N* were detected in the WPS intermediate water (WPS-IW, σθ = 26.5~27.1 kg m-3) around depth of 600-800 m (especially at a southern site) when compared to those of the conventional water source coming from North Pacific Intermediate Water (NPIW). By combining nitrate concentration, N* and δ15NNO3 as constraints, we propose that an additional southerly source other than NPIW may feed into the WPS-IW. On the other hand, the SCS intermediate water (SCS-IW, ~400-700 m), which supposedly sourced from WPS-IW along similar isopycnal levels, showed ~1‰ lower δ15NNO3 and δ18ONO3 values. This reduction in nitrate duel isotopes indicates intense diapycnal mixing primarily due to basin-wide upwelling in the SCS interior. This is the first hand data in the SCS for deep profiles

  16. Photophysiological state of natural phytoplankton communities in the South China Sea and Sulu Sea

    Directory of Open Access Journals (Sweden)

    W. Cheah

    2013-07-01

    Full Text Available In recent years, an increasing number of studies on phytoplankton in the tropical South China Sea (SCS and Sulu Sea (SS have been conducted. However, still little is known about the photophysiological state of natural phytoplankton communities under varying environmental conditions. This study investigates the photophysiological state of natural phytoplankton communities in the southern SCS and SS based on high horizontal and vertical resolution field observations collected during the SHIVA (Stratosphere ozone: Halogens in a Varying Atmosphere cruise (SO 218 in November 2011 on board RV Sonne. At the surface, pigment results revealed that total chlorophyll a (TChl a concentrations at all offshore stations were low at the surface and were generally dominated by cyanobacteria. Enhanced concentrations of TChl a were only observed below the upper mixed layer and above the euphotic depth with haptophytes, prochlorophytes and prasinophytes contributing most of the biomass. At stations close to the coast and river outflows, surface phytoplankton blooms (between 1 to 2.2 mg m−3 dominated by diatoms were observed. Overall, the study region exhibited strong nitrate + nitrite (NOx, −1, and phosphate (PO4, −1 depletion from surface down to about 50–60 m. Silicate (Si exhibited similar trends with the exception of some near shore stations in which high Si concentrations (> 2 μmol L−1 were observed in conjunction with increased TChl a and diatoms concentrations. Surface NOx concentrations were observed to correlate positively with temperature (τ = 0.22, p n = 108, whereas negative correlations were reported between surface NOx (τ = −0.27, p n = 108, Si (τ = −0.68, p n = 108 and salinity indicating that the enhancement in nutrients at the surface was probably supplied through fresher and warmer river waters near the coast. In contrast, the opposite was observed between temperature, salinity and all nutrients in the water column suggesting

  17. Dynamics of the Water Circulations in the Southern South China Sea and Its Seasonal Transports

    Science.gov (United States)

    Ooi, See Hai; Samah, Azizan Abu; Akbari, Abolghasem

    2016-01-01

    A three-dimensional Regional Ocean Modeling System is used to study the seasonal water circulations and transports of the Southern South China Sea. The simulated seasonal water circulations and estimated transports show consistency with observations, e.g., satellite altimeter data set and re-analysis data of the Simple Ocean Data Assimilation. It is found that the seasonal water circulations are mainly driven by the monsoonal wind stress and influenced by the water outflow/inflow and associated currents of the entire South China Sea. The intrusion of the strong current along the East Coast of Peninsular Malaysia and the eddies at different depths in all seasons are due to the conservation of the potential vorticity as the depth increases. Results show that the water circulation patterns in the northern part of the East Coast of Peninsular Malaysia are generally dominated by the geostrophic currents while those in the southern areas are due solely to the wind stress because of negligible Coriolis force there. This study clearly shows that individual surface freshwater flux (evaporation minus precipitation) controls the sea salinity balance in the Southern South China Sea thermohaline circulations. Analysis of climatological data from a high resolution Regional Ocean Modeling System reveals that the complex bathymetry is important not only for water exchange through the Southern South China Sea but also in regulating various transports across the main passages in the Southern South China Sea, namely the Sunda Shelf and the Strait of Malacca. Apart from the above, in comparision with the dynamics of the Sunda Shelf, the Strait of Malacca reflects an equally significant role in the annual transports into the Andaman Sea. PMID:27410682

  18. Dynamics of the Water Circulations in the Southern South China Sea and Its Seasonal Transports.

    Directory of Open Access Journals (Sweden)

    Farshid Daryabor

    Full Text Available A three-dimensional Regional Ocean Modeling System is used to study the seasonal water circulations and transports of the Southern South China Sea. The simulated seasonal water circulations and estimated transports show consistency with observations, e.g., satellite altimeter data set and re-analysis data of the Simple Ocean Data Assimilation. It is found that the seasonal water circulations are mainly driven by the monsoonal wind stress and influenced by the water outflow/inflow and associated currents of the entire South China Sea. The intrusion of the strong current along the East Coast of Peninsular Malaysia and the eddies at different depths in all seasons are due to the conservation of the potential vorticity as the depth increases. Results show that the water circulation patterns in the northern part of the East Coast of Peninsular Malaysia are generally dominated by the geostrophic currents while those in the southern areas are due solely to the wind stress because of negligible Coriolis force there. This study clearly shows that individual surface freshwater flux (evaporation minus precipitation controls the sea salinity balance in the Southern South China Sea thermohaline circulations. Analysis of climatological data from a high resolution Regional Ocean Modeling System reveals that the complex bathymetry is important not only for water exchange through the Southern South China Sea but also in regulating various transports across the main passages in the Southern South China Sea, namely the Sunda Shelf and the Strait of Malacca. Apart from the above, in comparision with the dynamics of the Sunda Shelf, the Strait of Malacca reflects an equally significant role in the annual transports into the Andaman Sea.

  19. Dynamics of the Water Circulations in the Southern South China Sea and Its Seasonal Transports.

    Science.gov (United States)

    Daryabor, Farshid; Ooi, See Hai; Samah, Azizan Abu; Akbari, Abolghasem

    2016-01-01

    A three-dimensional Regional Ocean Modeling System is used to study the seasonal water circulations and transports of the Southern South China Sea. The simulated seasonal water circulations and estimated transports show consistency with observations, e.g., satellite altimeter data set and re-analysis data of the Simple Ocean Data Assimilation. It is found that the seasonal water circulations are mainly driven by the monsoonal wind stress and influenced by the water outflow/inflow and associated currents of the entire South China Sea. The intrusion of the strong current along the East Coast of Peninsular Malaysia and the eddies at different depths in all seasons are due to the conservation of the potential vorticity as the depth increases. Results show that the water circulation patterns in the northern part of the East Coast of Peninsular Malaysia are generally dominated by the geostrophic currents while those in the southern areas are due solely to the wind stress because of negligible Coriolis force there. This study clearly shows that individual surface freshwater flux (evaporation minus precipitation) controls the sea salinity balance in the Southern South China Sea thermohaline circulations. Analysis of climatological data from a high resolution Regional Ocean Modeling System reveals that the complex bathymetry is important not only for water exchange through the Southern South China Sea but also in regulating various transports across the main passages in the Southern South China Sea, namely the Sunda Shelf and the Strait of Malacca. Apart from the above, in comparision with the dynamics of the Sunda Shelf, the Strait of Malacca reflects an equally significant role in the annual transports into the Andaman Sea. PMID:27410682

  20. Tidal changes in the Yellow/East China Sea caused by the rapid sea-level rise during the Holocene

    Institute of Scientific and Technical Information of China (English)

    KatsutoUehara

    2001-01-01

    Two-dimensional numerical simulations of M2 and K1 tides were performed in order to assess the effect of the rapid sea level change occurring during the last 20000 years in the Yellow/East China Sea (YECS). Results were interpreted by utilizing the difference of the dynamical nature inherited in diurnal and semi-diurnal tides. M2 tides at the coastal region south of Korea exceeded 2 m in amplitude when the sea-level was low, and decreased as the water depth become larger. In the Yellow Sea, on the other hand, tidal amplitudes were small at the low sea-level stages and increased along with the sea-level rise. The way of the increase was not monotonic but with fluctuations, which was due to the movement of the standing wave nodes. An additional experiment with closing the Taiwan Strait revealed that changing the sill depth of the strait not only affects the M2 tides around the southeastern Chinese coast, but also modifies the tides around the southwestern coast of Korea. This result recall us the significa

  1. Evaluation of an ocean data assimilation system for Chinese marginal seas with a focus on the South China Sea

    Institute of Scientific and Technical Information of China (English)

    XU Dazhi; LI Xichen; ZHU Jiang; QI Yiquan

    2011-01-01

    Data assimilation is a powerful tool to improve ocean forecasting by reducing uncertainties in forecast initial conditions. Recently, an ocean data assimilation system based on the ensemble optimal interpolation (EnOI) scheme and HYbrid Coordinate Ocean Model (HYCOM) for marginal seas around China was developed. This system can assimilate both satellite observations of sea surface temperature (SST) and along-track sea level anomaly (SLA) data. The purpose of this study was to evaluate the performance of the system. Two experiments were performed, which spanned a 3-year period from January 1, 2004 to December 30, 2006, with and without data assimilation. The data assimilation results were promising, with a positive impact on the modeled fields. The SST and SLA were clearly improved in terms of bias and root mean square error over the whole domain. In addition, the assimilations provided improvements in some regions to the surface field where mesoscale processes are not well simulated by the model. Comparisons with surface drifter trajectories showed that assimilated SST and SLA also better represent surface currents, with drifter trajectories fitting better to the contours of SLA field than that without assimilation. The forecasting capacity of this assimilation system was also evaluated through a case study of a birth-and-death process of an anticyclone eddy in the Northern South China Sea (NSCS), in which the anticyclone eddy was successfully hindcasted by the assimilation system. This study suggests the data assimilation system gives reasonable descriptions of the near-surface ocean state and can be applied to forecast mesoscale ocean processes in the marginal seas around China.

  2. Taxonomic study on the family Mitridae (Mollusca: Gastropoda: Neogastropoda) from the China's seas. Subfamilies: Imbricariinae and Cylindromitrinae

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Ninteen species of subfamilies Imbricariinae and Cylindromitrinae, family Mitridae, are recorded from the China's seas. Of which, one genus and six species are recorded for the first time from China' s seas, i.e., genus Ziba Adams H and Adams A, Cancilla (Cancilla)carnicolor, Ziba duplilirata, Z. insculpta, Neocancilla circula, Scabricola (Scabricola) desetangsii, Scabricola (Swainsonia) ocellata ocellata.

  3. Implementation and application of a nested numerical storm surge forecast model in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    于福江; 张占海

    2002-01-01

    A nested numerical storm surge forecast model for the East China Sea is developed. A one-way relaxing nest method is used to exchange the information between coarse grid and fine grid. In the inner boundary of the fine grid model a transition area is set up to relax the forecast variables. This ensures that the forecast variables of the coarse model may transit to those of fine grid gradually, which enhances the model stability. By using this model, a number of hindcasts and forecast are performed for six severe storm surges caused by tropical cyclones in the East China Sea. The results show good agreement with the observations.

  4. Tectonics and Petroleum Potential of the East China Sea Shelf Rift Basin

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    There are two Cenozoic sedimentary basins in the East China Sea. They are the East China Sea shelf basin and the Okinawa Trough basin. The former can be divided into a western and an eastern rift region. The development of the shelf basin underwent continental-margin fault depression, post-rift and then tectonic inversion stages. Available exploration results show that the distribution of source rocks is controlled by the basin architecture and its tectonic evolution. In the Xihu depression, mudstones and coals are the main source rocks. The eastern rift region has good geological conditions for the formation of large oil and gas fields.

  5. A possible role of the South China Sea in ENSO cycle

    Institute of Scientific and Technical Information of China (English)

    王启; 刘秦玉; 胡瑞金; 谢强

    2002-01-01

    A data-based hypothesis on the role of the South China Sea (SCS) in ENSO cycle is proposed: during El Nifio, there are westerly wind anomaly over the western equatorial Pacific and positive SST anomaly in the eastern equatorial Pacific. Meanwhile anomalous convection moves to the central Pacific with anomalous sinking over Indonesian Archipelago. The latter can cause southerly wind anomaly over the north of South China Sea (NSCS) and makes the NSCS warmer. The warm NSCS can attract the anomalous convection to it in some degree. This attraction is in favor for producing easterly wind anomaly over the western equatorial Pacific, so it helps to form a cycle.

  6. Coastal Seafloor Observatory Of The East China Sea At Xiaoqushan And Its Primary Observations

    Science.gov (United States)

    Xu, H.; Xu, C.; Qin, R.; Zhang, Y.; Chen, H.

    2010-12-01

    The seafloor observation system becomes increasingly important infrastructure in ocean sciences, which transforms oceanic research from temporal investigation to long term observation. The East China Sea coastal seafloor observatory, located between 30°31'44"N,122°15'12"E and 30°31'34"N,122°14'40"E, is built near the Xiaoqushan island outside the Yangtze River estuary, on the inner East China Sea continental shelf. The East China Sea coastal seafloor observatory is part of the East China Sea seafloor observational network. The observatory consists of a composite power cable made of optical fiber and extending for more than 1 kilometer and a special junction box, which provide power and signal communication for different instruments. The special junction box, which has various waterproof plugs, connects to three different instruments installed in a trawl preventer. The submarine optical fiber composite power cable is landed on the platform by The East China Sea Branch, State Oceanic Administration of the People’s Republic of China, and the power is continuously supplied by the solar panels and solar battery on the top of the platform. The real time data are directly sent through the cable to the platform and are transmitted by CDMA wireless to the receiver at the State Key Laboratory of Marine Geology of Tongji University. Measurements at the observatory have been taken since 26 April, 2009. The observations include current speeds and their directions at different depths, suspended sediment concentration, temperature and salinity nearby the seabed. The more than one year preliminary results show that the current field and fine suspended sediment transport of East China Sea are complex and show considerable seasonal variation affected by the integrated influence of Changjiang diluted water, Taiwan warm current and the Yellow Sea coastal current. The successful establishment of the coastal seafloor observatory is the first step toward future development of the

  7. Historical records of eutrophication in Changjiang (Yangtze River estuary and its adjacent East China Sea

    Directory of Open Access Journals (Sweden)

    F. Cheng

    2012-06-01

    Full Text Available Two sediment cores from the Changjiang (Yangtze River estuary and its adjacent East China Sea were collected and studied for eutrophication history using paleoecological records of environmental changes over the last century. A multiproxy approach by using biological and geochemical analyses revealed changes in diatom assemblages, total organic carbon (TOC, total nitrogen (TN and biogenic silica (BSi and give an indication of nutrient in status and trends in Changjiang River estuary and its adjacent East China Sea. The diatom assemblages in the two cores generally increased gradually from the 1970s, and accelerated from the 1990s until now, reflecting the increased eutrophication and causing large algae blooms/red tides. The TOC, TN and BSi showing the similar trends, supported the interpretation of the eutrophication process indicated by diatom analyses. The two cores were located in different sea areas of the East China Sea, and we discuss their relative changes based on their environment characteristics. We also discuss the potential effect of anthropogenic influences and ongoing projects on eutrophication in the Changjiang River and its adjacent East China Sea.

  8. Sea surface height oscillation with quasi-four-month period along the continental slope in the northern South China Sea

    Institute of Scientific and Technical Information of China (English)

    CHOW Chun Hoe; LIU Qinyu

    2012-01-01

    The sea surface height oscillation with a quasi-four-month period (SSHO4) along continental slope in the northern South China Sea (NSCS) is detected using satellite altimeter data and an ocean model simulation.The SSHO4 is at southwest of Dongsha Island,and is characterized by a wavelength of~600 km and a southwestward phase speed of~0.1 rn/s.Crossing the climatological background SST front,geostrophic currents corresponding to the SSHO4 generally induce sea surface temperature (SST) “tongues” during January-March.The cold and warm SST tongues appear southwest of cyclonic and anticyclonic eddies,respectively.The distance between the warm and cold SST tongues is about half the wavelength of the SSHO4.The geostrophic currents play an important r01e in lateral mixing,as manifested by the SST tongue phenomena in the NSCS.

  9. Quantitative relationship between flagellate abundance and suspended particle density in Huanghai Sea and East China Sea in summer

    Institute of Scientific and Technical Information of China (English)

    HUANG Lingfeng; PAN Ke; GUO Feng

    2006-01-01

    An investigation was carried out in the Huanghai Sea and the East China Sea to study the quantitative relationship between the abundance of flagellates and the density of suspended particles in the summer of 2001. The results show that the abundance of flagellates varies from 44~12 600 cell/cm3, and flagellates sometimes constitutes a significant part of suspended particles. The size-spectra of suspended particles can be divided into four categories: flat spectrum, humped spectrum, plankton spectrum and mixed spectrum. In general, the abundance of flagellates varies in proportion to the density of suspended particles. However, their quantitative relations reveal different characteristics in the seawater samples of different types of particle-size spectrum. This is only a preliminary study of the quantitative relationship between flagellates and suspended particles, which might lead to a potential convenient approach to the estimation of flagellate abundance in the sea.

  10. Sea-level trend in the South China Sea observed from 20 years of along-track satellite altimetric data

    DEFF Research Database (Denmark)

    Cheng, Yongcun; Xu, Qing; Andersen, Ole Baltazar

    2014-01-01

    The sea-level trend in the South China Sea (SCS) is investigated based on 20 years of along-track data from TOPEX and Jason-1/2 satellite altimetry. The average sea-level rise over all the regions in the study area is observed to have a rate of 5.1 ± 0.8 mm year-1 for the period from 1993 to 2012...... year-1 exhibited in the northern portion of the SCS. This is validated by comparing the altimetric data with the DAC-corrected tide gauge data at Xisha. In the southern SCS, the trend in wet troposphere correction, which is based on radiometer measurements on board the satellite, should be considered...

  11. Distribution of Organic Matter, Iron, Mangenese in Surface Sediments in the Nansha Islands Sea Area, South China Sea

    Institute of Scientific and Technical Information of China (English)

    Zhou Weihua; Wu Yunhua; Chen Shaoyong; Yin Kedong

    2003-01-01

    Concentrations of organic matter, iron and manganese in the deep sea surface sediments in the Nansha Islands sea area, South China Sea are measured. Horizontal and vertical distributions of iron and manganese are discussed. The vertical distribution of iron and manganese in the sediments results from reduction, diffusion, and redeposition of manganese (or iron) oxide and hydroxide in the sediment. There are the maxima of iron and manganese in solid phase in the top of the sediment, which is caused by the penetration of O2 and the upward flux of Mn2+ ( or Fe2+ ). Manganese bacteria play a very important role in the cycle of solid-phase iron and manganese in the ocean environment. Manganese bacteria oxidize Mn2+ ( or Fe2+ ) in dissolved state to Mn4+ ( or Fe3+ ) in oxidized state under the aerobic condition, whereas they reduce iron and manganese in anaerobic conditions.

  12. Retrieval of Secchi disk depth in the Yellow Sea and East China Sea using 8-day MODIS data

    International Nuclear Information System (INIS)

    Secchi disk depth (SDD), is widely used as an indicator of water clarity. The traditional sampling method is not only time-consuming and labor-intensive but also limited in terms of temporal and spatial coverage. Remote sensing technology may deal with these limitations. In this paper, the applicability of 8-day MODIS-Aqua remote sensing reflectance data with 4 km spatial resolution for estimating water clarity in the Yellow Sea and the East China Sea was investigated. Field data such as Secchi depths were collected from two cruises conducted in the Yellow Sea and the East China Sea from 5 May to 7 June 2009. A three-band algorithm to retrieve SDD was developed based on remote sensing reflectance at bands of 488, 555, and 678 nm, which performed better than single-band model and band ratio algorithm, with a determination coefficient of 0.72 and a mean relative error of 19%. This suggests that 8-day MODIS-Aqua products of remote sensing reflectance could be used to assess water transparency in the study area

  13. Antibiotics in the offshore waters of the Bohai Sea and the Yellow Sea in China: Occurrence, distribution and ecological risks

    International Nuclear Information System (INIS)

    The ocean is an important sink of land-based pollutants. Previous studies showed that serious antibiotic pollution occurred in the coastal waters, but limited studies focused on their presence in offshore waters. In this study, eleven antibiotics in three different categories were investigated in offshore waters of the Bohai Sea and the Yellow Sea in China. The results indicated that three antibiotics dehydration erythromycin, sulfamethoxazole and trimethoprim occurred throughout the offshore waters at concentrations of 0.10–16.6 ng L−1 and they decreased exponentially from the rivers to the coastal and offshore waters. The other antibiotics all presented very low detection rates (−1). Although the concentrations were very low, risk assessment based on the calculated risk quotients (RQs) showed that sulfamethoxazole, dehydration erythromycin and clarithromycin at most of sampling sites posed medium or low ecological risks (0.01 −1. ► Their concentrations decreased exponentially from the rivers to the offshore waters. ► Some antibiotics in the offshore water posed medium or low risks to some organisms. -- Some antibiotics were ubiquitous in the offshore waters of the Bohai Sea and the Yellow Sea in China and posed medium or low ecological risks to some sensitive organisms

  14. A Regional Ocean Reanalysis System for Coastal Waters of China and Adjacent Seas

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    A regional ocean reanalysis system for the coastal waters of China and adjacent seas has been developed by the National Marine Data and Information Service(NMDIS).It produces a dataset package called CORA (China ocean reanalysis).The regional ocean model used is based on the Princeton Ocean Model with a generalized coordinate system(POMgcs).The model is parallelized by NMDIS with the addition of the wave breaking and tidal mixing processes into model parameterizations.Data assimilation is a sequential three-dimensional variational(3D-Var) scheme implemented within a multigrid framework.Observations include satellite remote sensing sea surface temperature(SST),altimetry sea level anomaly(SLA),and temperature/salinity profiles.The reanalysis fields of sea surface height,temperature,salinity,and currents begin with January 1986 and are currently updated every year. Error statistics and error distributions of temperature,salinity and currents are presented as a primary evaluation of the reanalysis fields using sea level data from tidal gauges,temperature profiles,as well as the trajectories of Argo floats.Some case studies offer the opportunity to verify the evolution of certain local circulations.These evaluations show that the reanalysis data produced provide a good representation of the ocean processes and phenomena in the coastal waters of China and adjacent seas.

  15. A Regional Ocean Reanalysis System for Coastal Waters of China and Adjacent Seas

    Institute of Scientific and Technical Information of China (English)

    HAN Guijun; LI Wei; ZHANG Xuefeng; LI Dong; HE Zhongjie; WANG Xidong; WU Xinrong; YU Ting; MA Jirui

    2011-01-01

    A regional ocean reanalysis system for the coastal waters of China and adjacent seas has been developed by the National Marine Data and Information Service (NMDIS). It produces a dataset package called CORA (China ocean reanalysis). The regional ocean model used is based on the Princeton Ocean Model with a generalized coordinate system (POMgcs). The model is parallelized by NMDIS with the addition of the wave breaking and tidal mixing processes into model parameterizations. Data assimilation is a sequential three-dimensional variational (3D-Var) scheme implemented within a multigrid framework. Observations include satellite remote sensing sea surface temperature (SST), altimetry sea level anomaly (SLA), and temperature/salinity profiles. The reanalysis fields of sea surface height, temperature, salinity, and currents begin with January 1986 and are currently updated every year. Error statistics and error distributions of temperature, salinity and currents are presented as a primary evaluation of the reanalysis fields using sea level data from tidal gauges, temperature profiles, as well as the trajectories of Argo floats. Some case studies offer the opportunity to verify the evolution of certain local circulations. These evaluations show that the reanalysis data produced provide a good representation of the ocean processes and phenomena in the coastal waters of China and adjacent seas.

  16. Sedimentary architecture of the Bohai Sea China over the last 1 Ma and implications for sea-level changes

    Science.gov (United States)

    Shi, Xuefa; Yao, Zhengquan; Liu, Qingsong; Larrasoaña, Juan Cruz; Bai, Yazhi; Liu, Yanguang; Liu, Jihua; Cao, Peng; Li, Xiaoyan; Qiao, Shuqing; Wang, Kunshan; Fang, Xisheng; Xu, Taoyu

    2016-10-01

    Sedimentary architecture dominated by transgression-regression cycles in the shallow Bohai shelf region contains information about global sea-level, climate and local tectonics. However, previous studies of transgression-regression cycles in this region at orbital timescales that extend back to the early Pleistocene are sparse, mainly because of the shortage of well-dated long cores. Although transgression-regression sedimentary cycles in the region have been interpreted in terms of local tectonics, sea-level, and climate change, the detailed structure of marine transgressions and their significance for Quaternary global sea-level variations remains to be examined. In this study, we present an integrated sedimentological, geochemical and paleontological study of a 212.4 m (∼1 Ma) core (BH08) recovered from the Bohai Sea, China, for which an astronomically-based age model is available. Correspondence between marine-terrestrial sedimentary cycles and global sea-level fluctuations suggests that stacking of marine and terrestrial sediments was driven mainly by glacio-eustatic sea-level fluctuations in a context in which tectonic subsidence was largely balanced by sediment supply over the last ∼1 Ma. We report a dominant 100-kyr cycle beginning at ∼650 ka, which reflects the worldwide influence of the mid-Pleistocene transition (MPT) in sea-level records. We find that neritic deposits after the MPT were relatively thicker than before the MPT, which indicates an important control of the MPT on sedimentary architecture through lengthening of the duration of sea-level highstands.

  17. On the relationship between convection intensity of South China Sea summer monsoon and air-sea temperature difference in the tropical oceans

    Institute of Scientific and Technical Information of China (English)

    LIN Ailan; LIANG Jianyin; GU Dejun; WANG Dongxiao

    2004-01-01

    The annual, interannual and inter-decadal variability of convection intensity of South China Sea (SCS) summer monsoon and air-sea temperature difference in the tropical ocean is analyzed, and their relationship is discussed using two data sets of 48-a SODA (simple ocean data assimilation) and NCEP/NCAR. Analyses show that in wintertime Indian Ocean (WIO), springtime central tropical Pacific (SCTP) and summertime South China Sea-West Pacific (SSCSWP), air-sea temperature difference is significantly associated with the convection intensity of South China Sea summer monsoon. Correlation of the inter-decadal time scale (above 10 a) is higher and more stable. There is interdecadal variability of correlation in scales less than 10 a and it is related with the air-sea temperature difference itself for corresponding waters. The inter-decadal variability of the convection intensity during the South China Sea summer monsoon is closely related to the inter-decadal variability of the general circulation of the atmosphere. Since the late period of the 1970s, in the lower troposphere, the cross-equatorial flow from the Southern Hemisphere has intensified. At the upper troposphere layer, the South Asian high and cross-equatorial flow from the Northern Hemisphere has intensified at the same time. Then the monsoon cell has also strengthened and resulted in the reinforcing of the convection of South China Sea summer monsoon.

  18. Inter-shelf nutrient transport from the East China Sea as a major nutrient source supporting winter primary production on the northeast South China Sea shelf

    Directory of Open Access Journals (Sweden)

    A. Han

    2013-02-01

    Full Text Available The East China Sea (ECS and the South China Sea (SCS are two major marginal seas of the north Pacific with distinct seasonal primary productivity. Based upon field observation in December 2008–January 2009 covering both the ECS and the northern SCS (NSCS in wintertime, we examined southward long-range nutrient-transport from the ECS to the northeast SCS (NESCS carried by the China Coastal Current (CCC driven by the northeast prevailing monsoon. These nutrients escaped from the cold ECS shelf to refuel the primary production on the NESCS shelf where river-sourced nutrients were limited yet water temperature remained favorable. By coupling the field observation of nitrate + nitrite (DIN with the volume transport of the CCC, we derived a first order estimate of DIN flux of ~ 1430 ± 260 mol s−1. This DIN flux was ~ 7 times the wintertime DIN input from the Pearl River, a primary riverine nutrient source to the NSCS. By assuming DIN was the limiting nutrient, such southward DIN transport would have stimulated ~ 8.8 ± 1.6 × 1011 gC of new production (NP, accounting for ~ > 58 ± 10% of the total NP or ~ 38 ± 7–24 ± 4% of primary production on the NESCS shelf shallower than 100 m.

  19. Numerical simulation of scatterometer assimilated wind and ocean wave in eastern China seas and adjacent waters

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Using the latest version of Mesoscale Modeling System (MM5v3), we assimilated wind data from the scatterometer and built a model to assimilate the wind field over eastern China seas and adjacent waters and applied the wave model WAVEWATCH-Ⅲ to test the sea area with assimilative wind and blended wind of QSCAT and NCEP as driving forces. High precision and resolution numerical wave results were obtained.Analysis indicated that ifwe replace the model wind result with the blended wind, better sea surface wind results and wave results could be obtained.

  20. An Objective Analysis Method for Surface Residual Current Field in the East China Seas

    Institute of Scientific and Technical Information of China (English)

    WANG Qiang; WANG Cizhen

    2003-01-01

    Since the volume transport across the pycnocline is much smaller than that in the mixed layer, the current in the mixed layer can be regarded as non-divergent. An objective analysis method is deduced based on this hypothesis. The linear combination method is used to solve the non-divergent component of the current field of an ocean basin containing islands,which is equivalent to a mathematical problem of solving a Poisson equation in a multi-connected domain. The method is applied to the Bohai Sea, the Yellow Sea and the East China Sea (ECS). The modeled result is consistent with the current maps constructed by other oceanographers.

  1. Optical properties of sea ice in Liaodong Bay, China

    Science.gov (United States)

    Xu, Zhantang; Yang, Yuezhong; Wang, Guifen; Cao, Wenxi; Li, Zhijun; Sun, Zhaohua

    2012-03-01

    Many industrial, agricultural, and residential areas surrounding Liaodong Bay are responsible for much of the particulate matter (PM) and colored dissolved organic matter (CDOM) found in the sea ice in the bay. Understanding the optical properties of "dirty" sea ice is important for analyzing remote sensing data and calculating energy balances. We designed a hyperspectral radiation instrument to observe the optical properties of sea ice. The results show that albedo peaks ranged from 0.3 to 0.85 and that the peaks shifted to a longer wavelength for high PM and CDOM concentrations. The absorption and scattering coefficients for sea ice were obtained. The bulk absorption coefficient shows that bulk absorption is primarily determined by PM and CDOM at shorter wavelengths, while pure ice and brine pockets become more important at longer wavelengths. Scattering coefficients for sea ice ranged from 197 to 1072 m-1, and showed consistent variations with gas bubble and brine pocket concentrations. The effects of PM and CDOM on the bulk absorption coefficient of sea ice were studied. At 440 nm, particulates accounted for 55-98% and CDOM accounted for 2-37% of the bulk absorption. Ratios between particulate absorption and bulk absorption for sea ice were almost constant from 400 to 550 nm, and began to decrease sharply for wavelengths >550 nm. Ratios between CDOM and bulk absorption decreased almost linearly with increasing wavelength.

  2. Biomass of meiobenthic in the Bohai Sea, China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A grid of 22 stations, giving a broad geographic coverage of the Bohai Sea and the Bohai Strait was selected. Undisturbed sediments were collected from sampling stations during cruises in June 1997, in September/October 1998 and again in April/May 1999. Based on the results of Juario (1975),the average biornass, 0.404 g/(m2@ a) of meiofauna (including nematode, harpacticoida, bivalve larvae,polycheata and kinorhyncha) in the Bohai Sea is given and accounts for 4.5 percent of the macrofauna in the Bohai Sea. The horizontal distribution of the biomass of meiofauna showed that it was higher at the stations of middle east part of the Bohai Sea and the strait in 1998 and 1999 cruises and it decreased at the stations near to the strait mouth and increased at Station B1 in 1999 cruise. The annual average pro duction in the Bohai Sea is 3. 636 g/m2 calculated in term of the formula P = 9B. Compared with the biomass of other sea areas in the world, the biomass of the Bohai Sea is similar but slightly lower. The individual average dry weight of nematodes given by different authors is analyzed.

  3. Comparison of modern pollen distribution between the northern and southern parts of the South China Sea

    Science.gov (United States)

    Luo, Chuanxiu; Chen, Muhong; Xiang, Rong; Liu, Jianguo; Zhang, Lanlan; Lu, Jun

    2015-04-01

    The authors conducted a palynological analysis based on different number of air pollen samples for the northern and southern parts of the South China Sea, respectively, in order to give a reference to reconstruct the paleoclimate of the area. (1) Fifteen air pollen samples were collected from the northern part of the South China Sea from August to September 2011, and 13 air pollen samples were collected from the southern part of the South China Sea in December 2011. The pollen types were more abundant in the north than in the south. The total pollen number and concentration in the north was 10 times more than that in the south, which may be because of the sampling season. Airborne pollen types and concentrations have a close relationship with wind direction and distance from the sampling point to the continent. (2) Seventy-four samples were collected from surface sediments in the northern part of the South China Sea in the autumn. Thirty-three samples were collected from surface sediments in the southern part of the South China Sea in the winter. Pollen concentrations in the north were nearly 10 times higher than that in the south. This is because trilete spores are transported by rivers from Hainan Island to the sea and also by the summer monsoon-forced marine current. (3) Ten air pollen samples and 10 surface sediments samples were selected for comparison. The pollen and spores in the air were mainly herbaceous and woody pollen, excluding fern spores, having seasonal pollen characteristics. Pollen in the surface sediments were mainly trilete, Pinus, and herbaceous, and may also show a combination of annual pollen characteristics.

  4. Distribution of the East China Sea continental shelf basins and depths of magnetic sources

    Science.gov (United States)

    Lin, J.-Y.; Sibuet, J.-C.; Hsu, S.-K.

    2005-11-01

    The acoustic basement map of the East China Sea, established by the Shanghai Offshore Petroleum Bureau with all available industry seismic data, shows the existence of a 30-km-wide, 10-km-deep basin, that we named the Ho Basin. The Ho Basin belongs to a series of elongated deep basins extending over 600 km east of the Taiwan-Sinzi Ridge and flanked to the East by a ridge named the Longwan Ridge in its northern part. This new system of basin and ridge was probably formed during middle Miocene, sometimes in between rifting episodes occurring in the Taipei Basin and Okinawa Trough. It complements the already defined system of five belts of backarc basins and associated arc volcanic ridges in the East China Sea, which are progressively younger from the Mainland China shoreline (late Cretaceous/early Tertiary) to the Okinawa Trough (Present). In order to determine the crustal thickness beneath the East China Sea continental shelf, we used a power spectrum method to calculate the depth of the top (Zt) and the centroid (Zo) of the magnetic basement by fitting a straight line through the high- and low-wave number portions of the power spectrum, respectively. Then, the depth of the base (Zb)is estimated from Zt and Zo. After optimizing the size of the data squares, we demonstrate that, except for basins more than 10 km deep, Zt corresponds to the basement depths and Zb, the depth of the Curie point, to the Moho depth. As wide-angle reflection and refraction data are scarce in the East China Sea, this method provides a way to characterize the crustal thickness of the East China Sea and to compute the theoretical heat flow values.

  5. Spatial distributions of floating seaweeds in the East China Sea from late winter to early spring.

    Science.gov (United States)

    Mizuno, S; Ajisaka, T; Lahbib, S; Kokubu, Y; Alabsi, M N; Komatsu, T

    2014-01-01

    Floating seaweeds play an important role as a habitat for many animals accompanying or attaching to them in offshore waters. It was in 2000 that the first report described abundant distributions of floating seaweeds in offshore waters in the East China Sea in spring. Young individuals of the yellowtail Seriola quinqueradiata are captured for aquaculture purposes from floating seaweeds in the East China Sea. Therefore, a sound understanding of the distributions of floating seaweeds in the East China Sea is needed. Detailed information is especially important during the late winter to early spring, which corresponds to the juvenile period of the yellowtail. Thus, field surveys using R/V Tansei-Maru were conducted in the Japanese Exclusive Economic Zone in the East China Sea from late winter to early spring in 2010 and 2011. We obtained positions of the vessel by GPS and transversal distances from the vessel to a raft by visual observation. Distance sampling method (Thomas et al. 2010) was applied to estimation of floating seaweed densities (rafts km(-2)). Seaweed rafts were also randomly sampled using nets during the research cruises. In the East China Sea, seaweed rafts were distributed mainly on the continental shelf west of the Kuroshio, especially in waters between 26° N and 30° N. Collected rafts consisted of only one species, Sargassum horneri (Turner) C. Agardh. Taking into account surface currents and geographical distribution of S. horneri, it is estimated that these floating seaweeds originated from natural beds along the coast between mid and south China. Considering the approximate travel times, it is suggested that floating patches are colonized by yellowtails early on during their trips, i.e., close to the Chinese coast. PMID:24771973

  6. Monthly sea surface temperature records reconstructed by δ18O of reef-building coral in the east of Hainan Island,South China Sea

    Institute of Scientific and Technical Information of China (English)

    HE; Xuexian(何学贤); LIU; Dunyi(刘敦一); PENG; Zicheng(彭子成); LIU; Weiguo(刘卫国)

    2002-01-01

    Stable oxygen isotopic compositions of a coral colony of Porites lutea obtained on a core allowed the reconstruction of a 56-a (1943-1998) proxy record of the sea surface temperatures. This coral δ18O data are from the east of Hainan Island water (22°20′N, 110°39′E), South China Sea. The relationship between δ18O in the skeletal aragonite carbonate and the sea surface temperature (SST) is SST = -5.36 δ18OPDB-3.51 (r = 0.73, n = 470), dδ18O/d(SST) = -0.187‰/ ℃; and the thermometer was set at monthly resolution. The 56-a (1943-1998) proxy record of the sea surface temperatures reflected the same change trend in the northern part of South China Sea as the air temperature change trend in China.

  7. Distribution of Dissolved Inorganic Phosphate in Nansha Islands Sea Area,Southern South China Sea

    Institute of Scientific and Technical Information of China (English)

    程塞伟; 林洪瑛

    2004-01-01

    Based on the survey data from the program Multidisciplinary Expedition to Nansha Islands Sea Area, the distribution of dissolved inorganic phosphate ( PO43--P ) in the sea water of Nansha Islands Sea Area is comprehensively analyzed in this paper. The results show that PO43--P concentration in the sea water of southeastern Nansha Islands Sea Area is commonly higher than that in the other sea areas; the vertical distribution of PO43--P concentration varies inconspicuously in different seasons; the concentration of PO43--P increases with water depth and changes most greatly in the layer of 50 ~ 100 m. The diurnal variation of PO43--P concentration differs in different seasons and at different observation stations. The distribution and variation of PO43--P concentration result from the physical and biological processes together.

  8. 宽鳃鮟鱇属一新种%A NEW SPECIES OF THE GENUS SLADENIA (PISCES, LOPHIIDAE) FROM THE EAST CHINA SEA AND THE SOUTH CHINA SEA

    Institute of Scientific and Technical Information of China (English)

    倪勇; 伍汉霖; 李生

    2012-01-01

    A new lophiid anglerfish of the deep water genus Sladenia is described based on four specimens collected from the East China Sea and the South China Sea during the period from 1980 to 1982.Sladenia Regan ( 1908 ) is a genus of lophiid anglerfish with rounded rather than depressed head, and compressed rather than depressed tail; nasal sacs not constricted at the base; very long pseudobranchia; humeral, subopercular, quadrate, parietal and articular spines absent; epiotic and interopercular spines low and rounded; vomerine teeth larger than palatine teeth; illicial bone and second dorsal spine inserting very close together on illicial pterygiophore; third or third and fourth dorsal spines invisible, hiding under the skin of post-cephalic portion; and smooth ridge on frontal bones anterior to eyes and lateral to illicial pterygiophore.There were only four specimens, identified as 3 species, I. E., S. Gardineri Regan, 1908, S. Remiger Smith et Radcliffe, 1912 and S. Shaefersi Caruso et Bullis 1976, belonging to the genus Sladenia in the world before 1976. During the period from 1980 to 1982, the RV "Dongfang" and the RV "Nanfeng" of the East China Sea Fisheries Institute and the South China Sea Fisheries Research Institute respectively, completed a survey of the deep water fish fauna of the East and South China Seas. Four separate Chinese specimens of the rare lophiid anglerfish genus Sladenia were collected. With detailed analysis of the four rare specimens, it was recognized that they should belong to the same species, and also a new species named as Sladenia zhui.%20世纪70年代以前,全世界已知宽鳃鮟鱇属Sladenia Regan( 1908)鱼类仅有3种.1980~1982年期间,东海水产研究所“东方”号和南海水产研究所“南锋”号调查船分别在东海和南海的大陆架渔场调查时,共采集到4尾珍稀的深海鮟鱇鱼类.经研究,认为这4尾标本是1新种,定名为朱氏宽鳃鮟鱇Sladenia zhui sp.nov..

  9. Tidal elevation, current, and energy flux in the area between the South China Sea and Java Sea

    Science.gov (United States)

    Wei, Zexun; Fang, Guohong; Dwi Susanto, R.; Rameyo Adi, Tukul; Fan, Bin; Setiawan, Agus; Li, Shujiang; Wang, Yonggang; Gao, Xiumin

    2016-04-01

    The South China Sea (SCS) and the Java Sea (JS) are connected through the Karimata Strait, Gaspar Strait, and the southern Natuna Sea, where the tides are often used as open boundary condition for tidal simulation in the SCS or Indonesian seas. Tides, tidal currents, and tidal energy fluxes of the principle constituents K1, O1, Q1, M2, S2, and N2 at five stations in this area have been analyzed using in situ observational data. The results show that the diurnal tides are the dominant constituents in the entire study area. The constituent K1 has the largest amplitude, exceeding 50 cm, whereas the amplitudes of M2 are smaller than 5 cm at all stations. The amplitudes of S2 may exceed M2 in the Karimata and Gaspar straits. Tidal currents are mostly of rectilinear type in this area. The semi-major axes lengths of the diurnal tidal current ellipses are about 10 cm s-1, and those of the semidiurnal tidal currents are smaller than 5 cm s-1. The diurnal tidal energy flows from the SCS to the JS. The semidiurnal tidal energy flows from the SCS to the JS through the Karimata Strait and the eastern part of the southern Natuna Sea but flows in the opposite direction in the Gaspar Strait and the western part of the southern Natuna Sea. Harmonic analysis of sea level and current observation also suggest that the study area is located in the antinodal band of the diurnal tidal waves, and in the nodal band of the semidiurnal tidal waves. Comparisons show that the existing models are basically consistent with the observational results, but further improvements are necessary.

  10. Contrasting behavior of tungsten and molybdenum in the Okinawa Trough, the East China Sea and the Yellow Sea

    Energy Technology Data Exchange (ETDEWEB)

    Sohrin, Yoshiki; Matsui, Masakazu; Nakayama, Eiichiro

    1999-10-01

    By using catalytic current polarography and high-resolution inductively coupled plasma mass spectrometry, W and Mo in seawater were determined in the Okinawa Trough, a backarc rift, and in the East China Sea and the Yellow Sea. Mo was distributed conservatively throughout the study area, and its salinity-normalized concentration was 104 {+-} 6 nM (n = 105). W was also uniformly distributed south of the Kuroshio Current (56 {+-} 7 pM, n = 51). Anomalous high concentrations of W (maximum 254 pM) were found in the Iheya Graben in the middle Okinawa Trough ({gt}1,000 m depth), which were probably supplied by hydrothermal activity. The concentrations of Mo and W in the East China Sea and the Yellow Sea showed linear correlation with salinity (26 {lt} S {lt} 35). The Mo data can be explained by mixing of seawater and river water of the Changjiang (Mo = 10 nM; Qu et al., 1993). However, the values of W extrapolated to S = 0 were largely different between two cruises (1,200 pM in May-June 1987 and 540 pM in June 1994) and much higher than the reported concentrations of 160 pM for world rivers by Turekian (1969) and 30 pM for unpolluted Japanese rivers by Sohrin et al. (1989). Moreover, significantly high W was observed in the bottom water at stations near the Changjiang River estuary and the western Yellow Sea. While these data may suggest that W is released from the anoxic sediments of the continental shelf, more data are needed to elucidate the mechanism controlling the distribution of W.

  11. Numerical Forecasting Experiment of the Wave Energy Resource in the China Sea

    Directory of Open Access Journals (Sweden)

    Chong Wei Zheng

    2016-01-01

    Full Text Available The short-term forecasting of wave energy is important to provide guidance for the electric power operation and power transmission system and to enhance the efficiency of energy capture and conversion. This study produced a numerical forecasting experiment of the China Sea wave energy using WAVEWATCH-III (WW3, the latest version 4.18 wave model driven by T213 (WW3-T213 and T639 (WW3-T639 wind data separately. Then the WW3-T213 and WW3-T639 were verified and compared to build a short-term wave energy forecasting structure suited for the China Sea. Considering the value of wave power density (WPD, “wave energy rose,” daily and weekly total storage and effective storage of wave energy, this study also designed a series of short-term wave energy forecasting productions. Results show that both the WW3-T213 and WW3-T639 exhibit a good skill on the numerical forecasting of the China Sea WPD, while the result of WW3-T639 is much better. Judging from WPD and daily and weekly total storage and effective storage of wave energy, great wave energy caused by cold airs was found. As there are relatively frequent cold airs in winter, early spring, and later autumn in the China Sea and the surrounding waters, abundant wave energy ensues.

  12. A new species of the genus Linuparus White, from the South China Sea (Crustacea Decapoda)

    NARCIS (Netherlands)

    Bruce, A.J.

    1965-01-01

    The palinurid genus Linuparus White, 1847, has been represented by a single recent species, Linuparus trigonus (Von Siebold). The trawl survey of the northern shelf region of the South China Sea at present being carried out by the R.V. "Cape St. Mary" of the Fisheries Research Station, Hong Kong, ha

  13. Nannastacidae (Crustacea: Cumacea) from the Malayan shallow waters (South China Sea)

    NARCIS (Netherlands)

    Petrescu, Iorgu

    1997-01-01

    Four new species from the South China Sea are described: Nannastacus muelleri n.sp., Nannastacus wisseni n.sp., Scherocumella fagei n.sp. and Scherocumella malayensis n.sp. The descriptions of further 15 known species are complemented with new information ( Campylaspis amblyoda Gamo, 1960, Cumella c

  14. New species of the genus Sinularia (Octocorallia: Alcyonacea) from Nha Trang Bay, South China Sea, Vietnam

    NARCIS (Netherlands)

    Dautova, T.N.; Ofwegen, van L.P.; Savinkin, O.V.

    2010-01-01

    A total of eight Sinularia species is described and depicted, all from Nha Trang Bay, Vietnam (South China Sea). Six are new to science: S. capricornis, S. multiflora, S. pumila, S. sarmentosa, S. torta, and S. uva. Two other ones represent just new records for Vietnam: S. rigida (Dana, 1846) and S.

  15. The boat people of Vietnam. Rescue on the South China Sea.

    Science.gov (United States)

    Hayes, T J; Thomas, D; Dewar, E P

    1990-01-01

    Poor economic conditions in Vietnam have encouraged large numbers of people seeking a better life in the West to join the flow of political refugees leaving the country as "boat people". We report the events surrounding one such group of people who were rescued from the South China Sea by the Outback 88 Task Group.

  16. Dissolved Cu, Pb, Zn and Cd in the South China Sea surface waters

    Institute of Scientific and Technical Information of China (English)

    Huo Wenmian; Ji Weidong; Xu Kuncan

    2001-01-01

    A total of 106 surface water samples were collected in the South China Sea during two transects in June and December 1998. The samples were collected with strictly contamination free procedure and trace metals were measured by clean laboratory methods and GFAAS. The mean concentrations for the dissolved fractions are: Cu 0.100 μg/dm3, Pb 0.060 μg/dm3, Zn 0.086 μg/dm3, Cd 0.007 μg/dm3, which is close to the world open ocean's level. The spatial distribution of the trace heavy metals shows higher concentrations in offshore area and lower concentrations in the central in the South China Sea, and the concentrations decrease with the distance from the offshore, which suggests the existence of significant continental shelf input of the trace heavy metals. The correlationship among the elements is better in summer than that in winter. Cu is positively correlated with Cd in both seasons and it is also found for the first time that they are positively correlated with nutrients in the South China Sea surface waters which further indicate the biogeochemical cycle of these elements in the marine environment. The baseline value of Cu, Pb, Zn, Cd in the South China Sea surface waters is obtained through statistical analysis.

  17. Distribution of nanoflagellates in five water masses of the East China Sea in autumn and winter

    Science.gov (United States)

    Lin, Shiquan; Huang, Lingfeng; Zhu, Zhisheng; Xiong, Yuan; Lu, Jiachang

    2016-02-01

    The variations of abundance, biomass and trophic structure of nanoflagellates (NF) among five typical water masses in the East China Sea were investigated in autumn (November 19-December 23, 2006) and winter (February 22-March 11, 2007). It was found that water mass had a significant impact on the distribution of NF. Either in autumn or in winter, the highest abundance and biomass of NF were recorded in the East China Sea Shelf Mixing Water (ECSSMW), and the lowest in the Kuroshio Subsurface Water (KSSW). While in the East China Sea Coastal Water (ECSCW), the abundance and biomass of both heterotrophic nanoflagellates (HNF) and pigmented phototrophic nanoflagellates (PNF) were only slightly higher than that in Taiwan Strait Water (TSW) and Kuroshio Surface Water (KSW). In respect to the seasonal variation, the abundance and biomass of NF in TSW declined in winter, while in other 4 water masses, they showed an increasing trend from autumn to winter, mainly due to the decrease (in TSW) or increase (in ECSCW, ECSSMW, KSW and KSSW) of HNF. The distribution pattern of abundance- or biomass-based PNF/HNF ratio was found to be correlated to the nutrient level of the water mass. Results of Pearson correlation analysis and principle component analysis indicated that PNF was mainly constrained by nutrient supply, and HNF was controlled by food availability in the East China Sea.

  18. The East China Sea maritime and territorial dispute: a stand-off that suits everybody?

    DEFF Research Database (Denmark)

    O'Shea, Paul

    2016-01-01

    Over the past 20 years the East China Sea territorial and maritime dispute has become a key flashpoint in East Asia. Although the dispute has caused diplomatic and economic damage, its existence suits the key actors involved, thus reducing the incentive for resolution. The dispute undergirds the...

  19. Application of adjoint assimilation technique in simulating tides and tidal currents of the Bohai Sea, the Yellow Sea and the East China Sea

    Institute of Scientific and Technical Information of China (English)

    Cheng Yongcun; Lu Xianqing; Liu Yuguang; Xu Qing

    2007-01-01

    Considering the interaction of different tidal waves, an adjoint numerical model is developed to simulate M2, S2, K1 and O1 tidal waves in the Bohai Sea, the Yellow Sea and the East China Sea(B-Y-E) simultaneously. Compared with previous researches, by using the adjoint assimilation technique to inverse open boundary conditions and bottom friction coefficients based on altimetric data from TOPEX/Poseidon (T/P)and tidal gauges data, the precision of the numerical simulation is significantly improved. Selecting 14 days of simulated results after t11e initial warming run to conduct harmonic analysis, the results can show the characteristics of M2, S2, K1 and O1 tidal wave systems perfectly in B-Y-E. Compared with 9 current stations, the calculated harmonic constants of tidal currents for M2 and K1 are in good agreement With the observed ones.

  20. Chinese Assertiveness in the South China Sea and Southeast Asian Responses

    Directory of Open Access Journals (Sweden)

    Carlyle A. Thayer

    2011-01-01

    Full Text Available This article reviews Chinese assertive behaviour towards the Philippines and Vietnam over South China Sea issues in 2011. The article compares and contrasts Chinese diplomatic behaviour in the period before and after the adoption by ASEAN member states and China of Guidelines for the Implementation the Declaration on Conduct of Parties in the South China Sea in July. In the first period China aggressively asserted its claims to sovereignty by interfering with commercial fishing and oil exploration activities of vessels operating in the Exclusive Economic Zones of Vietnam and the Philippines. Both states resisted Chinese actions. The Philippines allocated increased funding for defence modernization, lobbied ASEAN states and shored up its alliance with the United States. Vietnam too protested Chinese action and undertook symbolic steps to defend national sovereignty. In the second period all states moved to contain South China Sea tensions from affecting their larger bilateral relations. It remains to be seen, however, if proposed confidence building measures will ameliorate Chinese assertiveness.

  1. What Depth Should Deep-Sea Water be Pumped up from in the South China Sea for Medicinal Research?

    Institute of Scientific and Technical Information of China (English)

    HE Shan; LIU Hongbing; YANG Xue; LI Chunxia; GUAN Huashi

    2013-01-01

    In this study,seawater was pumped up from 150,200,300,500 and 1000m in the South China Sea and analyzed to make certain what depth should deep-sea water (DSW) be pumped up for medicinal usage.The pumping depth of DSW was determined on the basis of chemical ingredients.The analyses of inorganic elements and dissolved organic matter (DOM) were performed by inductively coupled plasma mass spectrometry (ICP-MS) and ultra performance liquid chromatography-mass spectrometry (UPLC-MS) respectively.The raw data were used for hierarchical cluster analysis (HCA) and principal component analysis (PCA).The results showed that seawater pumped up from 500m and 1000m was similar in their chemical ingredients,and was different from the seawater pumped up from other depths.These results indicated that seawater from more than 500 m depth had relatively stable chemical ingredients and could be used as DSW in the South China Sea.

  2. Data from renewable energy assessments for resort islands in the South China Sea

    Directory of Open Access Journals (Sweden)

    M. Reyasudin Basir Khan

    2016-03-01

    Full Text Available Renewable energy assessments for resort islands in the South China Sea were conducted that involves the collection and analysis of meteorological and topographic data. The meteorological data was used to assess the PV, wind and hydropower system potentials on the islands. Furthermore, the reconnaissance study for hydro-potentials were conducted through topographic maps in order to determine the potential sites suitable for development of run-of-river hydropower generation. The stream data was collected for 14 islands in the South China Sea with a total of 51 investigated sites. The data from this study are related to the research article “Optimal combination of solar, wind, micro-hydro and diesel systems based on actual seasonal load profiles for a resort island in the South China Sea” published in Energy (Khan et al., 2015 [1].

  3. Preliminary Design of Offshore Wind Turbine Tension Leg Platform In the South China Sea

    Directory of Open Access Journals (Sweden)

    Hai-feng Wang

    2013-12-01

    Full Text Available China has the richest offshore wind resource in the world. Much of undeveloped resource should consider floating tension leg platform (TLP wind turbine because of its advantage and potential in cost and safety for deep sea, but the related research is short in China. In this thesis we assess a preliminary design for a type of TLP structure in the South China Sea (SCS-TLP closed to Guangdong province basing on NREL 5MW wind turbine. By coupled analysis in the time domain, the platform displacement and tower base force are obtained and analyzed. As a result, SCS-TLP has good features in the dynamic response except yaw motion, it needs to improve the yaw direction damping to induce motion in this direction.

  4. Time trends of polybrominated diphenyl ethers in East China Seas: Response to the booming of PBDE pollution industry in China.

    Science.gov (United States)

    Li, Yuanyuan; Lin, Tian; Hu, Limin; Feng, Jialiang; Guo, Zhigang

    2016-01-01

    The East China Seas (ECSs) are the receptors of the land-based persistent organic pollutants (POPs), such as polybrominated diphenyl ethers (PBDEs) mainly from China through atmospheric deposition driven by the East Asian winter monsoon and fluvial discharge (e.g., Yangtze River and Yellow River), making the offshore sediments to be a good proxy to reconstruct history of those pollutants in China. In this work, four well-placed sediment cores were extracted from the mud areas in the ECSs, and the (210)Pb-dated cores were analyzed to yield historical concentration profiles of PBDEs in the area. The results showed that there was a persistent increase from 1970s and almost no clear sign in the decline of PBDEs until recently in China. More importantly, there was a faster increase of PBDEs from 1990s in China; while this period was just shown as gradually leveling off or even declining trends in developed countries. The persistently increasing trend of PBDEs in China since 1990s could be largely due to the booming of the manufacturing industry and unexpectedly transfer of PBDE pollution from developed countries to China. Besides, the relative high concentrations and fluxes of PBDEs in the core from coastal ECS located near a well-known electrical/electronic waste (e-waste) recycling area suggests an important contribution of PBDE emissions from recycling centers of e-waste in China. Although efforts in environmental monitoring of PBDE contamination have been substantially increased over the last decade, China is still lagging behind in terms of nationwide regulation of PBDE usage and treatment of disposal PBDE-containing products. PMID:27179303

  5. Progress of Large-Scale Air-Sea Interaction Studies in China

    Institute of Scientific and Technical Information of China (English)

    蒲书箴; 赵进平; 于卫东; 赵永平; 杨波

    2004-01-01

    This paper summarizes the progress of large-scale air-sea interaction studies that has been achieved in China in the four-year period from July 1998 to July 2002, including seven aspects in the area of the air-sea interaction, namely air-sea interaction related to the tropical Pacific Ocean, monsoon-related air-sea interaction, air-sea interaction in the north Pacific Ocean, air-sea interaction in the Indian Ocean, air-sea interactions in the global oceans, field experiments, and oceanic cruise surveys. However more attention has been paid to the first and the second aspects because a large number of papers in the reference literature for preparing and organizing this paper are concentrated in the tropical Pacific Ocean, such as the ENSO process with its climatic effects and dynamics, and the monsoon-related air-sea interaction. The literature also involves various phenomena with their different time and spatial scales such as intraseasonal, annual, interannual, and interdecadal variabilities in the atmosphere/ocean interaction system, reflecting the contemporary themes in the four-year period at the beginning of an era from the post-TOGA to CLIVAR studies. Apparently, it is a difficult task to summarize the great progress in this area, as it is extracted from a large quantity of literature, although the authors tried very hard.

  6. Microgastropod records in paleoceanographical environment of southern shelf of South China Sea since 14 ka

    Institute of Scientific and Technical Information of China (English)

    冯伟民

    2002-01-01

    Very diversified and abundant benthic microgastropods and planktonic microgastropods (pteropods) from core NS93-12-25 could provide a glance of change of the sea level in the south continental shelf of the South China Sea since last 14 ka. Research shows that general sea level changes of this sea area were rising and later rising after a short period of falling in this period. In the range from the bottom of the core to the core depth of 200 cm, individuals in big size are common in microgastropods and Turritella filiola is very rich, signifying the environment of the inner continental shelf in the last deglaciation stage. In the core depth range of 200—150 cm the continuously getting light of the ??18O, the regularly decreasing of the percentage content of T. filiola and the high diversification of microgastropods indicate the rising of the sea level. Especially at the core depth range of 175—150 cm the pteropods became dominant, making sure the fact that the high sea level possibly occurred in the early Holocene. Channels of surrounding straits connecting the adjacent sea thus were opened. But at the core depth of about 100 cm T. filiola became very rich again. This possibly implies that there was a short term of the sea level falling, resulting in the temporal closure of the channels. In the core depth range of 55—50 cm the Scaliola' s representatives relatively develop and this may be inferred to the cooling of climate.

  7. 一南海问题与中国南部地缘安全%The South China Sea Issue and Geo-security in the South China

    Institute of Scientific and Technical Information of China (English)

    李国选

    2014-01-01

    冷战后,南海的地缘位置与地缘环境决定了南海的价值。然而,南海问题的存在深刻地影响着南海地区的和平与发展,特别是对中国南部的地缘安全的制约作用日益明显。南海问题使中国不能有效地维护中国在南海的海域安全,不能有力地保证中国的战略航道安全,并且阻碍中国南部地缘环境的持续改善。中国应采取必要的对策消除南海问题对中国南部地缘安全的制约作用。%After the Cold War, the geopolitical location and geopolitical environment of the South China Sea determines the value of the South China Sea. However, the existence of the South China Sea dispute has a profound impact on peace and development in the South China Sea region, especially on China’s south geo-security. The South China Sea dispute makes China not effectively protect maritime security in the South China Sea, not effectually ensure the security of China’s strategic waterways and impede the geopolitical environment in southern China to improve continuously. China should take necessary measures to eliminate the negative effect that the South China Sea dispute has on China’s geo-security.

  8. Sea surface height anomaly and geostrophic circulation variations in the South China Sea from TOPEX/POSEIDON altimetry

    Institute of Scientific and Technical Information of China (English)

    刘克修; 马继瑞; 许建平; 韩桂军; 范振华

    2002-01-01

    --The sea surface height anomaly (SSHA) and geostrophic circulation in the South ChinaSea (SCS) are studied using TOPEX/POSEIDON (T/P) altimetry data. The SSHA, which is obtained after tidal correction based on the tidal results from T/P data, is predominated by seasonal alternating monsoons. The results reveal that the SSHA in the central part of the SCS is positive in spring and summer, but negative in autumn and winter. It is also found that the SSHA in the SCS can be approached with the sum of tidal constituents SA and SSA. The geostrophic circulations in the SCS are calculated according to sea surface dynamic topography, which is the sum of SSHA and mean sea surface height. It is suggested that the circulation in the upper layer of the SCS is generally cyclonic and notably western intensified during autumn and winter, while the western intensification is weak during spring and summer. It is also indicated that the Kuroshio intrudes into the northeastern SCS throuth the Luzon Strait in winter. But there is no indication of Kuroshio intruding into the SCS in summer.

  9. Coupling and propagating of mesoscale sea level variability between the western Pacific and the South China Sea

    Institute of Scientific and Technical Information of China (English)

    LI Li; JING ChunSheng; ZHU DaYong

    2007-01-01

    The coupling and propagating features of mesoscale sea level variability between the western Pacific(WP)and the South China Sea(SCS)were studied based on time series analyses of satellite altimeter measured,along-track sea surface height anomalies(SSHA)along 21°N and the slope of the northern SCS.The analyses show that mesoscale sea level fluctuations in the WP have rather limited coherent effects on the SCS,and no statistically significant propagation of mesoscale variability through the Luzon Strait was observed except in the 45-day band.Evidence suggests that the 45-day fluctuation is very much likely a character of the Kuroshio originating from its low-latitude beginning.It is also suggested that the westward propagating Rossby waves will deform when they encounter the dynamical barrier of the Kuroshio.The Kuroshio will then acts on the SCS in its own way.The SCS is a relatively isolated system in the sense of coupling and propagating of oceanic mesoscale waves.

  10. Three-dimensional calculations of the currents in the Huanghai Sea and East China Sea during June of 1999

    Institute of Scientific and Technical Information of China (English)

    Huiqun Wang; Yaochu Yuan; Yonggang Liu; Mingyu Zhou

    2003-01-01

    Based on the wind and hydrographic data obtained by R/V Xiangyanghong 14 duringJune of 1999, the currents in the Huanghai Sea and East China Sea are computed by the three dimen-sional non-linear diagnostic, semidiagnostic models and prognostic in the σ coordinate. The computed re-sults show that the density and velocity fields and so on have been adjusted when time is about 3 days,namely the solution of semidiagnostic calculation is obtained. In the northwest part of the computed re-gion, the Huanghai coastal current flows southeastward, and then it flows out the computed region southof Cheju Island. In the west side of the southern part of the computed region, there is other current,which is mainly inshore branch of Taiwan Warm Current, and it flows cyclonically and turns to thenortheast. In the region north of the above two currents, there is a cyclonic eddy southwest of Cheju Is-land, and it has characteristics of high density and low temperature. There is an offshore branch of Tai-wan Warm Current in the west side of the Kuroshio, and it makes a cyclonic meander, then flows north-eastward. The Kuroshio in the East China Sea is stronger, and flows northeastward. Its maximum hori-zontal velocity is 108.5 cm/s at the sea surface, which is located at the northern boundary, and it is106.1 cm/s at 30 m level, 102.2 cm/s at 75 m level and 85.1 cm/s at 200 m level, respectively, whichare all located at the southern boundary. Comparing the results of diagnostic calculation with those ofsemidiagnostic and prognostic calculations indicates that the horizontal velocity field agrees qualitatively,and there is a little difference between them in quantity. The comparison between the computed veloci-ties and the obeered velocities at the mooring station show that they agree each other.

  11. Coupling between SST and wind speed over mesoscale eddies in the South China Sea

    Science.gov (United States)

    Sun, Shuangwen; Fang, Yue; Liu, Baochao; ᅟ, Tana

    2016-11-01

    The coupling between sea surface temperature (SST) and sea surface wind speed over mesoscale eddies in the South China Sea (SCS) was studied using satellite measurements. Positive correlations between SST anomalies (SSTA) and wind speed anomalies were found over both cyclonic and anticyclonic eddies. In contrast to the open oceans, the spatial patterns of the coupling over mesoscale eddies in the SCS depend largely on the seasonal variations of the background SST gradient, wind speed, and wind directional steadiness. In summer, the maximum SSTA location coincides with the center of eddy-induced sea surface height anomalies. In winter, the eddy-induced SSTA show a clear dipole pattern. The spatial patterns of wind speed anomalies over eddies are similar to those of the SSTA in both seasons. Wind speed anomalies are linearly correlated with SSTA over anticyclonic and cyclonic eddies. The coupling coefficients between SSTA and wind speed anomalies in the SCS are comparable to those in the open oceans.

  12. Ancient Changjiang channel system in the East China Sea continental shelf during the last glaciation

    Institute of Scientific and Technical Information of China (English)

    LI; Guangxue; LIU; Yong; YANG; Zigeng; YUE; Shuhong; YANG

    2005-01-01

    Based on the data of high-resolution seismic profiles, an ancient river channel system of the last glaciation occurred along the Zhedong and Xihu depression in the southeast of Hupijiao rise. The distribution of the channel fill system shows that the ancient Changjiang River went through the Changjiang depression into the low land plain of the outside continental shelf during the low sea level cycle of the last glaciation. The big channel fill into Okinawa Trough is not found due to the depletion of the river kinetic energy in the low land plain. The river discharge dispersal was of an important role to the dilution of the northern Okinawa Trough sea at that time. Six ancient river channel systems (A―F), which are main distributaries of ancient Changjiang in the East China Sea continental shelf during the last glaciation, may be buried off the modern Changjiang estuary. The distribution of these channels coincides with the zonal elevations in the sea floor.

  13. Modern movement and deformation in the South China Sea shown by GPS measurements and numerical simulation

    Institute of Scientific and Technical Information of China (English)

    WANG Jing; LUAN Xiwu; YU Roger Z.

    2013-01-01

    To better understand the crustal deformation of the South China Sea Basin,we produce a mechanically consistent 2-dimensional model for observing regional velocity field in the South China Sea (SCS).We studied the dominating regional tectonic stress field by geodetic measurements and finite element analysis,the spatial variations of velocity field and strain field,and relative movements among different blocks,using a 2-dimensional model describing crustal deformation of the South China Sea Basin.Strain results show that the SCS is extending at present.The western part of SCS is opening gradually in NW-SE direction from its northern margin to the south,but the eastern part of SCS is opening gradually from its central part to the north and south.In addition,we analyzed the plate kinematics to the deformation of the SCS,using a two-dimensional finite element model.Our simulations results are well explained by available geodetic data.The movement of SCS is resulted from interactions among Indian Plate,Pacific Plate,Philippine Sea Plate,and Eurasian Plate.

  14. Crustal activities recorded in coral reefs in the northwestern South China Sea

    Institute of Scientific and Technical Information of China (English)

    ZHAN Wenhuan; YAO Yantao; ZHANG Zhiqiang; SUN Zongxun; ZHAN Meizhen; SUN Longtao; LIU Zaifeng

    2006-01-01

    Coral reefs in the northwest of South China Sea have recorded the information from not only the environmental variation but also the crustal activities there during their development. The main crustal activities correlated with the coral reef development include fault, seismic, and volcano activities,etc. The high-resolution spark seismic profiles in the northwestern South China Sea show that the fault activities in the coral reef region have been clearly recorded, and appear as neonatal faults incising reefs. Earthquakes in the coral reef region are rather intense, especially the two occurring on December,31, 1994, and January, 10, 1995, around the southwest of Leizhou Peninsula, with the magnitude of 6.1and 6.2, respectively. They have great influence on the growth of the local coral reefs. Quaternary volcanos are active in the northwestern South China Sea, especially around the southwest of Leizhou Peninsula, and they have obvious control of the coral reef development. Some submarine volcanoes form the substrates of coral reef, while a few emerge above the sea surface and form coral islands.

  15. China-Japan Sea Route Sees New Development

    Institute of Scientific and Technical Information of China (English)

    BySunLimei

    2004-01-01

    ON November6,a super express service corporation that is formed by four Japanese companies in Shanghai would deploy high-speed Ro/Ro ships on the China-Japanroutes,pushing comperition on nautical speed to a new high.Yet the market signal that is sent via this upgrading of shipping speed would not be mere increased competition.

  16. Scenarios of Local Tsunamis in the China Seas by Boussinesq Model

    Institute of Scientific and Technical Information of China (English)

    赵曦; 刘桦; 王本龙

    2014-01-01

    The Okinawa Trench in the East China Sea and the Manila Trench in the South China Sea are considered to be the regions with high risk of potential tsunamis induced by submarine earthquakes. Tsunami waves will impact the southeast coast of China if tsunamis occur in these areas. In this paper, the horizontal two-dimensional Boussinesq model is used to simulate tsunami generation, propagation, and runup in a domain with complex geometrical boundaries. The temporary varying bottom boundary condition is adopted to describe the initial tsunami waves motivated by the submarine faults. The Indian Ocean tsunami is simulated by the numerical model as a validation case. The time series of water elevation and runup on the beach are compared with the measured data from field survey. The agreements indicate that the Boussinesq model can be used to simulate tsunamis and predict the waveform and runup. Then, the hypothetical tsunamis in the Okinawa Trench and the Manila Trench are simulated by the numerical model. The arrival time and maximum wave height near coastal cities are predicted by the model. It turns out that the leading depression N-wave occurs when the tsunami propagates in the continental shelf from the Okinawa Trench. The scenarios of the tsunami in the Manila Trench demonstrate significant effects on the coastal area around the South China Sea.

  17. Spatial and Temporal Distribution of Sea Surface Salinity in Coastal Waters of China Based on Aquarius

    International Nuclear Information System (INIS)

    Sea surface salinity (SSS) is a fundamental parameter for the study of global ocean dynamics, water cycle, and climate variability. Aquarius launched by NASA and the Space Agency of Argentina is a breakthrough which could achieve the remote sensing data of SSS. The present paper takes the coastal of China as study area, which is a representative area of ocean boundary and influenced by continental rivers (Yangtze River and Pearl River). After analyze the temporal and spatial variation of SSS in the coastal of China, the estuary area has obvious low salinity because the injected of freshwater from continent. Take the East China Sea (ECS) and South China Sea (SCS) as representative region to discuss the effect of freshwater to SSS. The salinity is almost equal in winter when the diluted water is inadequate in both rivers. However, an obvious decrease appeared in summer especial July in Yangtze River for abundance discharge inflow the ECS. This is a reasonable expression of Yangtze River discharge is remarkable influence the SSS in coastal area then Pearl River. Survey the distribution range of Yangtze River diluted water (SSS<31psu). The range is small in winter and expands to peak value in summer

  18. Seasonal variation of black carbon over the South China Sea and in various continental locations in South China

    Directory of Open Access Journals (Sweden)

    D. Wu

    2013-07-01

    Full Text Available Black carbon (BC is an important atmospheric constitute as an air pollutant and as a climate forcer. To our knowledge, field measurements of BC have not been reported over the South China Sea. Observation of light absorption coefficients (σabs and BC concentrations by Aethalometer were conducted on Yongxing Island in the South China Sea and at five continental sites in the Pearl River Delta (PRD region, South China during the South China Sea monsoon period (rainy season, 16 May–20 June 2008 and the northeast monsoon period (dry season, 12 December 2008–8 January 2009. At the oceanic site, the daily average BC concentrations vary from 0.28 to 2.14 μg m−3 and seasonal variations of BC were small (0.67 in dry season and 0.54 μg m−3 in rainy season. Similarly, little seasonal difference was found at a background site in PRD (2.88 in dry season and 2.62 μg m−3 in rainy season. At PRD urban sites, the daily average concentration of BC ranges from 1.56 to 37.9 μg m−3, higher in the dry season (12.6 μg m−3 and lower in the rainy season (6.4 μg m−3. The observed average σabs values in rainy vs. dry seasons are 119 vs. 62 Mm−1 at the PRD urban sites, 29 vs. 26 Mm−1 at the PRD background site, and 8.4 vs. 7.2 Mm−1 at the marine site. A bi-peak pattern in diurnal BC variation was observed at all sites while this pattern is the most prominent at the urban sites. The first peak appears in the early morning rush hour and the second peak in early evening, with the evening peak more pronounced in dry season.

  19. Black carbon and polycyclic aromatic hydrocarbons (PAHs) in surface sediments of China's marginal seas

    Institute of Scientific and Technical Information of China (English)

    KANG Yanju; WANG Xuchen; DAI Minhan; FENG Huan; LI Anchun; SONG Qian

    2009-01-01

    This study investigates the distribution of black carbon (BC) and its correlation with total polycyclic aromatic hydrocarbons (ΣPAH) in the surface sediments of China's marginal seas. BC content ranges from <0.10 to 2.45 mg/g dw (grams dry weight) in the sediments studied, and varied among the different coastal regions. The Bohai Bay sediments had the highest BC contents (average 2.18 mg/g dw),which comprises a significant fraction (27%-41%) of the total organic carbon (TOC) preserved in the sediments. In comparison, BC in the surface sediments of the North Yellow Sea, Jiaozhou Bay, East China Sea and the South China Sea is less abundant and accounted for an average of 6%, 8%, 14% and 5%,respectively, of the sedimentary organic carbon pool. The concentration of ΣPAH in the surface sediments ranges from 41 to 3 667 ng/g dw and showed large spatial variations among the sampling sites of different costal regions. The Bohai Bay has the highest ΣPAH values, ranging from 79 to 3 667 ng/g dw. This reflects the high anthropogenically contaminated nature of the sediments in the bay. BC is positively correlated to TOC but a strong correlation is not found between BC and ΣPAH in the surface sediments studied, suggesting that BC and PAHs preserved in the sediments are derived from different sources and controlled by different biogeochemical processes. Our study suggests that the abundance of BC preserved in the sediments could represent a significant sink pool of carbon cycling in China's marginal seas.

  20. Detrital zircon provenance of the Paleogene syn-rift sediments in the northern South China Sea

    Science.gov (United States)

    Shao, Lei; Cao, Licheng; Pang, Xiong; Jiang, Tao; Qiao, Peijun; Zhao, Meng

    2016-02-01

    The early rift sedimentation history of the South China Sea is still not well understood due to restricted borehole coverage of the Paleogene strata and lack of reliable stratigraphic dating. We use detrital zircon U-Pb geochronology to explore the source-to-sink characteristics of syn-rift sequences in the northern South China Sea. The results reveal significant intrabasinal provenances in addition to the well-perceived terrigenous supply from the north. The Dongsha Uplift is considered to account for the dominance of the Early Cretaceous zircons in the Eocene samples. The Lower Oligocene sediments in the Qiongdongnan Basin could have been sourced from Hainan Island and local uplifts, but their distinction cannot be confirmed by the U-Pb age spectra. Contemporary sediments in the northern Pearl River Mouth Basin were most likely transported from southeastern South China with well-rounded zircon grains showing U-Pb age similarity to those from the northeastern tributaries of the Pearl River. By contrast, intrabasinal sources from the west and east are suggested to have contributed the infill of the southern part of the Pearl River Mouth Basin based on generally euhedral zircon shapes. These sedimentary source patterns appear to change very little in the Oligocene northern South China Sea. However, the newly detected Neoproterozoic zircons in the Upper Oligocene sediments from borehole L21 tend to indicate a southern source. The episodic and diachronic nature of rifting and erosion processes in the early South China Sea is the cause of complex patterns in the Paleogene provenance history.

  1. Establishment of trophic continuum in the food web of the Yellow Sea and East China Sea ecosystem: Insight from carbon and nitrogen stable isotopes

    Institute of Scientific and Technical Information of China (English)

    CAI Deling; LI Hongyan; TANG Qisheng; SUN Yao

    2005-01-01

    Stable carbon and nitrogen isotope ratios (δ13C and δ15N) are used to study the trophic structure of food web in the Yellow Sea and East China Sea ecosystem. The trophic continuum of pelagic food web from phytoplankton to top preyer was elementarily established, and a trophic structure diagram in the Yellow Sea and East China Sea was outlined in combination with carbon isotopic data of benthic organisms, which is basically consistent with and makes some improvements on the simplified Yellow Sea food web and the trophic structure diagram drawn based on the biomass of main resource population during 1985―1986. This result indicates that the stable isotope method is a potential useful means for further studying the complete marine food web trophic continuum from viruses to top predators and food web stability.

  2. Establishment of trophic continuum in the food web of the Yellow Sea and East China Sea ecosystem: insight from carbon and nitrogen stable isotopes.

    Science.gov (United States)

    Cai, Deling; Li, Hongyan; Tang, Qisheng; Sun, Yao

    2005-12-01

    Stable carbon and nitrogen isotope ratios (delta (13)C and delta (15)N) are used to study the trophic structure of food web in the Yellow Sea and East China Sea ecosystem. The trophic continuum of pelagic food web from phytoplankton to top preyer was elementarily established, and a trophic structure diagram in the Yellow Sea and East China Sea was outlined in combination with carbon isotopic data of benthic organisms, which is basically consistent with and makes some improvements on the simplified Yellow Sea food web and the trophic structure diagram drawn based on the biomass of main resource population during 1985-1986. This result indicates that the stable isotope method is a potential useful means for further studying the complete marine food web trophic continuum from viruses to top predators and food web stability. PMID:16483132

  3. Enhanced sea-air CO2 exchange influenced by a tropical depression in the South China Sea

    Science.gov (United States)

    Sun, Qingyang; Tang, DanLing; Legendre, Louis; Shi, Ping

    2014-10-01

    Ship measurements made 2 days after the passage of a tropical depression (TD) in the South China Sea (SCS, April 2011) showed two contrasted responses of the partial pressure of CO2 at sea surface (pCO2,sw). In low sea-surface salinity (SSS) water, pCO2,sw was low (349 ± 7 μatm), and the area was a carbon sink (-4.7 ± 1.8 mmol CO2 m-2 d-1), whereas in water with high SSS and chlorophyll a and low dissolved oxygen and sea surface temperature, pCO2,sw was higher than for normal SCS water (376 ± 8 versus 362 ± 4 μatm) and the area was a carbon source (1.2 ± 3.1 mmol CO2 m-2 d-1). Satellite data showed two large areas of low SSS before the TD, which were likely influenced by rainfall, and these areas were considered to have low pCO2,sw because of their low SSS. The high pCO2,sw after the TD is explained by the uplifting to the surface of deeper and CO2-rich water, due to winds accompanied by the TD. The difference in sea-air CO2 flux between the TD-affected area and the lower-SSS water was 1.99 + 4.70 = 6.7 mmol CO2 m-2 d-1, indicating a 100% change caused by the TD compared to the average seasonal value in spring in southern SCS (3.3 ± 0.3 mmol CO2 m-2 d-1). Undersaturation of CO2 prior to the TD due to dilution by freshwater and the preexisting cold eddy, and slow translation speed of the TD, are considered to account for the CO2 flux change.

  4. Advances in Marine Microbial Symbionts in the China Sea and Related Pharmaceutical Metabolites

    Directory of Open Access Journals (Sweden)

    Zhiyong Li

    2009-04-01

    Full Text Available Marine animals and plants such as sponges, sea squirts, corals, worms and algae host diverse and abundant symbiotic microorganisms. Marine microbial symbionts are possible the true producers or take part in the biosynthesis of some bioactive marine natural products isolated from the marine organism hosts. Investigation of the pharmaceutical metabolites may reveal the biosynthesis mechanisms of related natural products and solve the current problem of supply limitation in marine drug development. This paper reviews the advances in diversity revelation, biological activity and related pharmaceutical metabolites, and functional genes of marine microbial symbionts from the China Sea.

  5. SST INTRASEASONAL OSCILLATION AND ATMOSPHERIC FORCING SYSTEM OF THE SOUTH CHINA SEA

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This study used National Center for Environmental Prediction (NCEP) reanalysis data to confirm that the variance of sea surface temperature (SST) in the South China Sea (SCS) has pronounced intraseasonal oscillations characterized by quasi-standing waves; and was aimed to document how intraseasonal time scale SST formed and developed in the SCS. The results derived from the composite analysis indicated the existence of a local low-level atmospheric dynamic forcing system over the SCS. The main formation mechanism of SST intraseasonal oscillation is the low-level rotational atmospheric circulation forcing over the SCS on intraseasonal time scales and the solar radiation variations caused by cloud amount changes.

  6. Hydrological, plankton and pigment observations in the South China Sea; 06 December 1971 to 28 December 1971 (NODC Accession 0000939)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This report records the data collected during the cruise of the R.V. Jalanidhi in the South China Sea and the water around the Seribu Islands. The region of the...

  7. A numerical study of the South China Sea deep circulation and its relation to the Luzon Strait transport

    Institute of Scientific and Technical Information of China (English)

    袁东亮

    2002-01-01

    A fine-resolution MOM code is used to study the South China Sea basin-scale circulation and its relation to the mass transport through the Luzon Strait. The modal domain includes the South China Sea, part of the East China Sea, and part of the Philippine Sea so that the currents in the vicinity of the Luzon Strait are free to evolve. In addition, all channels between the South China ,Sea and the Indonesian seas are closed so that the focus is on the Luzon Strait transport. The model is driven by specified Philippine Sea currents and by surface heat and salt flux conditions. For simplicity, no windstress is applied at the surface.The simulated Luzon Strait transport and the South China Sea circulation feature a sandwich vertical structure from the surface to the bottom. The Philippine Sea water is simulated to enter the South China Sea at the surface and in the deep ocean and is carried to the southern basin by western boundary currents. At the intermediate depth, the net Luzon Strait transport is out of the South China Sea and is fed by a western boundary current flowing to the north at the base of the thermocline. Corresponding to the western boundary currents, the basin circulation of the South China Sea is cyclonic gyres at the surface and in the abyss but an anti-cyclonic gyre at the intermediate depth. The vorticity balance of the gyre circulation is between the vortex stretching and the meridional change of the planetary vorticity.Based on these facts, it is hypothesized that the Luzon Strait transports are determined by the diapycnal mixing inside the entire South China Sea. The South China Sea plays the role of a "mixing mill" that mixes the surface and deep waters to return them to the Luzon Strait at the intermediate depth. The gyre structures are consistent with the Stommel and Arons theory (1960), which suggests that the mixlng-induced circulation inside the South China Sea should be cyclonic gyres at the surface and at the bottom but an anti

  8. Chemical, optical and other data collected aboard the MELVILLE during cruise MV0903 in the Philippine Sea, South China Sea (Nan Hai) and Sulu Sea from 2009-02-27 to 2009-03-21 (NODC Accession 0089605)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089605 includes chemical, optical, physical and underway data collected aboard the MELVILLE during cruise MV0903 in the Philippine Sea, South China...

  9. Interannual variations of bomb radiocarbon during 1977-1998 recorded in coral from Daya Bay, South China Sea

    Institute of Scientific and Technical Information of China (English)

    SHEN; Chengde(沈承德); YU; Kefu(余克服); SUN; Yanmin(孙彦敏); YI; Weixi(易惟熙); YANG; Ying(杨英); ZHOU; Bin(周斌)

    2003-01-01

    22 annual layered samples of coral from 1977 to 1998 were collected from Daya Bay, South China Sea, their bomb-14C(nuclear weapons testing 14C) concentrations were determined and studied, and the atmosphere-sea exchange rate and diffusion thickness were estimated and found to be 17 mol·m-2·a-1 and 32 μm, respectively. The interannual variation of coral △14C is mainly controlled by oceanic factors. In ENSO years, the coastwise upwelling current of South China Sea gets intensified, hence the coral △14C displays its bottom value. The coral △14Cdoes not respond vividly to the variation of the solar radiation energy. In thepast 20 years or so, the general situation and the oceanic thermal structure ofSouth China Sea are still stable even though interannual variation occurs in the atmosphere-sea interaction and the upwelling current driven by the tropical energy.

  10. Effects of the Indo-China Peninsula Heat Fluxes on the 1998 South China Sea Summer Monsoon

    Institute of Scientific and Technical Information of China (English)

    SHI Xueli; Johnny C. L. CHAN; K. C. CHOW; DING Yihui

    2005-01-01

    Sensitivity experiments to investigate the role and importance of the Indo-China Peninsula (ICP) heat fluxes (sensible and latent heat fluxes) on the South China Sea summer monsoon (SCSSM) onset and its subsequent evolution have been carried out using a regional climate model. Two sensitivity experiments have been conducted: cutting off the sensible heat flux (noted as IChfx) and latent heat flux (noted as ICqfx).Results show that by cutting off the underlying heat flux of the ICP, the precipitation decreases and low-level geopotential height increases over the local regions as well as the remote regions of the East China Sea, southern Japan, and western North Pacific. The westerly (easterly) zonal winds at 850 hPa (200 hPa)are generally weakened in May and June, especially before and during the onset of the SCSSM towards the end of May.It is worth noting that although the observed sensible heat flux is only about 1/3 of the latent heat flux,the differences between the control run and each of the two sensitivity experiments are comparable.

  11. Potassium-argon/argon-40-argon-39 geochronology of Cenozoic alkali basalts from the South China Sea

    Institute of Scientific and Technical Information of China (English)

    YAN Quanshu; SHI Xuefa; YANG Yaomin; WANG Kunshan

    2008-01-01

    Based on the isotopic chronologic results of Cenozoic alkali basalts from the South China Sea,the characteristics of volcanic activi-ty of the South China Sea after spreading were studied.The potassium - argon ages of eight alkali basalt samples from the South China Sea,and the argon - argon ages of two samples among them are reported.Apparent ages of the whole rock are 3.80 to 7.91 Ma with an average value of 5.43 Ma (potassium- argon,whole rock),and there is little difference among samples at the same location,e.g.,4.76~5.78 Ma for location S04-12.The argon - argon ages for the two samples are 6.06 and 4.71 Ma,which lie within the age scope of potassium - argon method.The dating results indicate that rock-forming age is from late Miocene to Pli-ocene,which is consistent with erupting event for alkali basalts from adjacent regions of the South China Sea.Volcanic activities occur after the cessation of spreading of the South China Sea,which are controlled by lithospheric fault and the spreading center formed during the spreading period of the South China Sea.These dating results,combined with geochemical characteristics of these basalts,the published chronological data for the South China Sea and its adjacent regions,and the updated geophysical data near Hainan Island,suggest that after the cessation of spreading of the South China Sea,there occur widely distributing magmatic activities which primarily is alkali basalt,and the volcanic activity continues to Quaternary.The activity may be relative to Hainan mantle plume originated from core/mantle boundary.

  12. Magnetic Susceptibility in Surface Sediments in the Southern South China Sea and Its Implication for Sub-sea Methane Venting

    Institute of Scientific and Technical Information of China (English)

    Chen Zhong; Yan Wen; Tang Xianzan; Liu Jianguo; Chen Muhong; Yang Huaping

    2009-01-01

    In order to understand the characteristics of magnetic variability and their possible implication for sub-sea methane venting,magnetic susceptibility (MS) of 145 surface sediment samples from the southern South China Sea (SCS) was investigated.Magnetic particles extracted from 20 representative samples were also examined for their mineral,chemical compositions and micromorphology.Results indicate that MS values range between -7.73×10-8 and 45.06x10-8 m3/kg.The high MS zones occur at some hydrecarbon-bearing basins and along main tectonic zones,and low ones are distributed mainly within the river delta or along continental shelves.Iron concretions and manganese concretions are not main contributors for high MS values in sediments,while authigenic iron sulphide minerals are possibly responsible for the MS enhancement.This phenomenon is suspected to be produced by the reducing environment where the high upward venting methane beneath the seafloor reacts with seawater sulfate,resulting in seep precipitation of highly susceptible intermediate mineral pyrrhotite,greigite and paramagnetic pyrite.It suggests that MS variability is possibly one of the geochemical indicators for mapping sub-sea zones of methane venting in the southern SCS.

  13. Simulation of the extreme waves generated by typhoon Bolaven (1215) in the East China Sea and Yellow Sea

    Institute of Scientific and Technical Information of China (English)

    JUN Ki Cheon; JEONG Weon Mu; CHOI Jin Yong; PARK Kwang Soon; JUNG Kyung Tae; KIM Mee Kyung; CHAE Jang Won; QIAO Fangli

    2015-01-01

    Record-breaking high waves occurred during the passage of the typhoon Bolaven (1215) (TYB) in the East China Sea (ECS) and Yellow Sea (YS) although its intensity did not reach the level of a super typhoon. Winds and directional wave measurements were made using a range of in-situ instruments mounted on an ocean tower and buoys. In order to understand how such high waves with long duration occurred, analyses have been made through measurement and numerical simulations. TYB winds were generated using the TC96 typhoon wind model with the best track data calibrated with the measurements. And then the wind fields were blended with the reanalyzed synoptic-scale wind fields for a wave model. Wave fields were simulated using WAM4.5 with adjustment ofCd for gust of winds and bottom friction for the study area. Thus the accuracy of simulations is considerably enhanced, and the computed results are also in better agreement with measured data than before. It is found that the extremely high waves evolved as a result of the superposition of distant large swells and high wind seas generated by strong winds from the front/right quadrant of the typhoon track. As the typhoon moved at a speed a little slower than the dominant wave group velocity in a consistent direction for two days, the wave growth was significantly enhanced by strong wind input in an extended fetch and non-linear interaction.

  14. Response of the South China Sea summer monsoon onset to air-sea heat fluxes over the Indian Ocean

    Institute of Scientific and Technical Information of China (English)

    CHEN Jinnian; ZUO Tao; WANG Hongna

    2012-01-01

    We objectively define the onset date of the South China Sea (SCS) summer monsoon,after having evaluated previous studies and considered various factors.Then,interannual and interdecadal characteristics of the SCS summer monsoon onset are analyzed.In addition,we calculate air-sea heat fluxes over the Indian Ocean using the advanced method of CORARE3.0,based on satellite remote sensing data.The onset variation cycle has remarkable interdecadal variability with cycles of 16 a and 28 a.Correlation analysis between air-sea heat fluxes in the Indian Ocean and the SCS summer monsoon indicates that there is a remarkable lag correlation between them.This result has important implications for prediction of the SCS summer monsoon,and provides a scientific basis for further study of the onset process of this monsoon and its prediction.Based on these results,a linear regression equation is obtained to predict the onset date of the monsoon in 2011 and 2012.The forecast is that the onset date of 2011 will be normal or 1 pentad earlier than the normal year,while the onset date in 2012 will be 1-2 pentads later.

  15. Two new species of Glyphocrangon (Decapoda: Caridea: Glyphocrangonidae) from the East China Sea and the Philippines.

    Science.gov (United States)

    Han, Qingxi; Li, Xinzheng

    2014-08-18

    The present paper reports two new species of Glyphocrangon (Crustacea, Caridea, Glyphocrangonidae) collected respectively from the East China Sea and the Philippines. G. singularis sp. nov., from the East China Sea, is similar to G. fimbriata Komai & Takeuchi, 1994 with the presence of fringe of setae on dactyl of the third to fifth pereopods, but differs from G. fimbriata by the rostrum shape and the armature on the carapace; G. denticulata sp. nov., from the Philippines, is similar to G. pugnax De Man, 1918 with the entire anterior third carina, but differs from G. pugnax by armatures of the antennal scaphocerite and carapace, the lengths of rostrum and the spines of fifth abdominal somite, and the colouration of carapace. 

  16. The deep thermal characteristic of continental margin of the northern South China Sea

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Heat flow plays an important role in the study of thermal structure and thermal evolution of continental margin of the northern South China Sea. The analysis of heat flow value shows that margin heat flow in the northern South China Sea is relatively high setting, but the percentage of crustal heat flow is lower than 35% in terrestrial heat flow. The terrestrial heat flow exhibited a current of rise from the Northern Continental Margin to the Southern Central Basin. However, the proportion of crustal heat flow in terrestrial heat flow slowly dropped down in the same direction. It is suggested that the main factor causing high heat flow setting is the moving up of hot material from asthenosphere.

  17. Preliminary numerical simulation of potential earthquake-induced tsunami in East China Sea

    Institute of Scientific and Technical Information of China (English)

    WEN Yan-lin; ZHU Yuan-qing; SONG Zhi-ping; XUE Yan; LIU Shuang-qing; DONG Fei-fei

    2008-01-01

    In this paper, we present a numerical simulation of the propagation of a tsunami in the East China Sea, which might be induced by a hypothetical M8.5 earthquake in Okinawa Trough. Our results show that the initial maxi-mum wave height of tsunami could reach as high as 4.3 m for the hypothetical earthquake. It would take 3.5~4 hours for the tsunami to propagate to the coast of Zhejiang Province, and 7~8 hours to the near-shore of Shanghai. The peak tsunami height could be up to about 2 m in the coast of Zhejiang Province. Based on the numerical ex-periments, we plot the arrival time contours of tsunami in East China Sea and time history curves on the three ob-servational stations, and discussed the significance of the pre-analysis.

  18. Dynamics of the Water Circulations in the Southern South China Sea and Its Seasonal Transports

    DEFF Research Database (Denmark)

    Daryabor, Farshid

    2016-01-01

    of Peninsular Malaysia and the eddies at different depths in all seasons are due to the conservation of the potential vorticity as the depth increases. Results show that the water circulation patterns in the northern part of the East Coast of Peninsular Malaysia are generally dominated by the geostrophic......A three-dimensional Regional Ocean Modeling System is used to study the seasonal water circulations and transports of the Southern South China Sea. The simulated seasonal water circulations and estimated transports show consistency with observations, e.g., satellite altimeter data set and re......-analysis data of the Simple Ocean Data Assimilation. It is found that the seasonal water circulations are mainly driven by the monsoonal wind stress and influenced by the water outflow/inflow and associated currents of the entire South China Sea. The intrusion of the strong current along the East Coast...

  19. Numerical simulation of rifting controlled by magmatic underplating in the South China Sea

    Science.gov (United States)

    Xu, Hehua

    2016-04-01

    South China Sea is one of the largest basins in the western Pacific marginal sea, which is located in the intersection area of the Eurasia, the India-Australian and the Pacific-Philippines plate. Although the duration of seafloor spreading and the extension mechanism are still controversial.It is widely accepted that the South China Sea was opened by seafloor spreading in the Cenozoic. From the point of its structural development history, South China Sea has its own unique development model, which is formed by the continent rifting and expansion, while the tectonic evolution has close relationship with geological peripheral units. According to the seismic detection and magnetic integrated geophysics, the studies found that high-speed lower crust layers are widespread in the northern South China Sea and the northeast of continental margin, these layers are mainly located in continental slopes and some high-degree tensional continental shelves. Researches suggested that materials of high-speed in lower crustal layers are formed by the bottom magmatic underplating rather than serpentinized mantle peridotite. These layers are formed in Cenozoic and has close relationship with extension. However, in most kinematic and dynamic models of rift formation and evolution, the effects of magmatism have been neglected. This study established a two-dimensional thermal - mechanical coupled finite element model to simulate the role of underplated magmatic bodies in the localization of deformation. We examine the response of the lithosphere to an applied constant boundary velocity at the edge of the model. The mamatic underplating is introduced as a material with an anomalous high temperture and a magic upper mantle composition. The mechanical problem is coupled with the thermal problem through temperature-dependent viscosity. Since extension of lithosphere and underlying mantle is associated with intense and simultaneous viscous and brittle/plastic(faulting) deformations, we use

  20. Characterization and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in Sediments from the Bohai Sea, China

    Science.gov (United States)

    Liu, Jihua; Hu, Ningjing; Shi, Xuefa

    2015-04-01

    Characterization and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in Sediments from the Bohai Sea, China Liu Jihua, Hu Ningjing, Shi Xuefa First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, China Polycyclic aromatic hydrocarbons (PAHs) are a class of ubiquitous organic contaminants in the environment. Indeed, 16 PAH compounds have been listed as priority pollutants by the United States Environmental Protection Agency and the European Union because of their potential toxicity to humans and ecosystems. As POPs are released or escape into the environment, their global accumulation in marine sediments generates a complex balance between inputs and outputs. Furthermore, PAHs in coastal sediments can serve as effective tracers of materials transport from land-to-sea (Fang et al., 2009). Hence, investigations of PAHs in sediments can provide useful information for further understanding of environmental processes and material transport. In this study, sixteen polycyclic aromatic hydrocarbons (PAHs) were extracted from a total of 112 surface sediment samples collected across the entire territory of the Bohai Sea. The detectable concentrations of PAHs ranged from 97.2 to 300.7 ng/g across all samples, indicating low contamination levels of PAHs compared with reported values for other coastal sediments in China and developed countries. The highest concentrations were found within three belts in the vicinity of Luan River Estuary-Qinhuangdao Harbor, the Cao River Estuary-Bohai Sea Center, and north of the Yellow River Estuary. The distribution patterns of PAHs and source identification implied that PAH contamination in the Bohai Sea mainly originates from offshore oil exploration, sewage discharge from rivers and shipping activities. Further Principal components analysis (PCA)/multivariate linear regression (MLR) analysis suggested that the contributions of spilled oil products (petrogenic), coal combustion and traffic

  1. Inter-annual sea level variability in the southern South China Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Soumya, M.; Vethamony, P.; Tkalich, P.

    -influenced inter-annual variations are found only in the southwestern and southeastern coastal regions of SSCS. Our analysis reveals that inter-annual regional sea level drops are associated with positive phase of the IOD, and the rises with negative phase...

  2. Bothid larvae (Pleuronectiformes - Pisces) of the Gulf of Thailand and South China Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Devi, C.B.L.

    . Any piece of additional or new information emerging out of subsequent search are of crucial importance to formulate more viable economic policies for better management of the ecosystem. The parameters which have direct relationship with growth... and exploitation of the vast resources of the Gulf of Thailand and the South China Sea which will have a salutory effect in improving the dietary requirements of the neighbouring populations. Fishes of the family Bothidae, regarded as more specialised than other...

  3. A new species of Amphictene ( Annelida , Pectinariidae ) from the northern South China Sea

    OpenAIRE

    Zhang,Jinghuai; Zhang, Yanjie; Qiu, Jian-Wen

    2015-01-01

    Abstract Pectinariids are a family of polychaetes commonly found in shallow coastal waters around the world, but their diversity is poorly known along the coasts of Asia. Here we describe Amphictene alata sp. n. ( Pectinariidae ), based on 15 specimens collected from the coastal waters of Guangdong in the northern South China Sea. This new species can be distinguished from all other 13 described species and one described subspecies of Amphictene by having a pair of dorsolateral lobes on segme...

  4. The South China Sea: analyzing fisheries catch data in an ecosystem context

    OpenAIRE

    Christensen, V.; Pauly, D

    1991-01-01

    The South China Sea is an important fishing area with an annual harvest of some 5 million tonnes, or 10% of the catches jointly taken by the developing nations of the world. Details are given of a model of the area describing fisheries catches and biological interactions. The area, viewed as a large marine ecosystem, was divided into 10 subsystems; each subsystem was then linked with adjacent subsystems by predatory links, and detritus flows. An analysis was then made of catch statistics for ...

  5. Seasonal variability of tropical cyclones generated over the South China Sea

    Institute of Scientific and Technical Information of China (English)

    WANG Guihua; WANG Hui; QI Yiquan

    2007-01-01

    The seasonal variability of tropical cyclones (CTCs) generated over the South China Sea (SCS) from 1948 to 2003 is analyzed. It peaks in occurrence in August and few generate in late winter (from January to March). The seasonal activity is attributed to the variability of atmosphere and ocean environments associated with the monsoon system. It is found that the monsoonal characteristics of the SCS basically determine the region of tropical cyclone (TC) genesis in each month.

  6. Study on spatial and temporal distribution of planktonic amphipoda in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    JIANG Mei; WANG Yunlong; YUAN Qi; CHEN Yaqu

    2004-01-01

    Quantitative distribution of planktonic amphipoda in the East China Sea is analyzed and the relation with environmental factors and mackerel and scad fishing grounds is studied. The result shows that the characteristic of biomass is great seasonal and interannual variety during the passing three decades. The distribution of planktonic amphipoda basically reflects the movement, decay and intensification of the different water systems in the survey area.

  7. Numerical assessment of factors affecting nonlinear internal waves in the South China Sea

    Science.gov (United States)

    Li, Qiang

    2014-02-01

    Nonlinear internal waves in the South China Sea exhibit diverse characteristics, which are associated with the complex conditions in Luzon Strait, such as the double ridge topography, the Earth’s rotation, variations in stratification and the background current induced by the Kuroshio. These effects are individually assessed using the MITgcm. The performance of the model is first validated through comparison with field observations. Because of in-phased ray interaction, the western ridge in Luzon Strait intensifies the semidiurnal internal tides generated from the eastern ridge, thus reinforcing the formation of nonlinear internal waves. However, the ray interaction for K1 forcing becomes anti-phased so that the K1 internal tide generation is reduced by the western ridge. Not only does the rotational dispersion suppress internal tide generation, it also inhibits nonlinear steepening and consequent internal solitary wave formation. As a joint effect, the double ridges and the rotational dispersion result in a paradoxical phenomenon: diurnal barotropic tidal forcing is dominant in Luzon Strait, but semidiurnal internal tides prevail in the deep basin of the South China Sea. The seasonal variation of the Kuroshio is consistent with the seasonal appearance of nonlinear internal waves in the South China Sea. The model results show that the westward inflow due to the Kuroshio intrusion reduces the amplitude of internal tides in the South China Sea, causing the weakening or absence of internal solitary waves. Winter stratification cannot account for the significant reduction of nonlinear internal waves, because the amplitude growth of internal tides due to increased thermocline tilting counteracts the reduced nonlinearity caused by thermocline deepening.

  8. Coccolithophore responses to environmental variability in the South China Sea: species composition and calcite content

    OpenAIRE

    Jin, X. B.; C. L. Liu; Poulton, A. J.; M. H. Dai; X.H. Guo

    2016-01-01

    Coccolithophore contributions to the global marine carbon cycle are regulated by the calcite content of their scales (coccoliths), and the relative cellular levels of photosynthesis and calcification. All three of these factors vary between coccolithophore species, and with response to the growth environment. Here, water samples were collected in the northern basin of the South China Sea (SCS) during summer 2014 in order to examine how environmental variability influenced species composition ...

  9. Analysis on the indicator species and ecological groups of pelagic ostracods in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    XU Zhaoli

    2008-01-01

    Ecological adaptation and ecological groups of pelagic ostraceds were examined in the East China Sea (23°30' ~ 33°00'N,118°30'~ 128°00'E),in relation to temperature and salinity.The data were collected in four surveys conducted from 1997 to 2000.The density,yield density,or negative exponent models were used to determine the optimal temperature and salinity of wa-ter for the thriving growth of pelagic ostracods.Thereafter,ecological groups and potential distribution patterns of pelagic ostracods were determined based on the predicted parameters such as optimal temperature and salinity,consulting the geographic distribu-tion.The analytical results indicate that,among the numerical dominant pelagic ostraceds in the East China Sea (ECS),Eucon-choecia aculeata,E.elongata,E.chierchiae,E.maimai,and Cypridina dentata,etc.are offshore subtropical water species.These species are widely distributed in the area,and they can be brought by the warm current to north offshore during spring and winter.The predicated optimal temperature (OT) and optimal salinity (OS) for Paraconchoecia decipiens,P.echinata,P.spini-fera,P.oblonga,Conchoecia magna and Porroecia porrecta are all greater than 25℃ and 34 separately.These species are mainly distributed in the waters of the Kuroshio,the Taiwan Warm Current,and the Taiwan Strait,and therefore are designated as ocean-ic tropical water species.On the other hand,Pseudoconchoecia concentrica is considered as offshore subtropical water species based on its geographical distribution although its OT is 19~C.The other species,though their OSs are approximately 34 and with OTs ranging from 20° to 25℃,are considered as offshore subtropical water species because they were found to be widely distribu-ted from the South China Sea to the East China Sea.

  10. Primary productivity and its variability in the equatorial South China Sea during the northeast monsoon

    OpenAIRE

    S. H. Ooi; Samah, A.A.; Braesicke, P.

    2013-01-01

    Near coastal areas of the equatorial South China Sea (SCS) are one of the world's regions with highest primary productivity (phytoplankton growth). Concentrations of phytoplankton in the SCS depend significantly on atmospheric forcings and the oceanic state, in particular during the northeast (winter) monsoon season from November to March. Aided by new ocean-observing satellite data, we present a climatological overview of recent surface atmospheric and oceanic features in the equatorial SCS ...

  11. Two new eunicellin diterpenoids from the East China Sea gorgonian Muricella sp.

    Science.gov (United States)

    Zhao, Chuan; Wang, Jia; Jin, De-Jun; Duan, Hong-Quan; Xing, Guo-Sheng; Tang, Sheng-An

    2016-09-01

    A phytochemical investigation on gorgonian Muricella sp. from East China Sea resulted in the isolation of eight eunicellin diterpenoids including two new ones, muricellins A-B (1, 2). Chemical structures of these compounds were elucidated by spectroscopic techniques (1D and 2D NMR and MS) and by comparison with data reported in the literature. Anti-rheumatoid arthritis activities of 1, 3, 4, and 6 have been evaluated. PMID:27004724

  12. Mesoscale eddies in the South China Sea and their impact on temperature profiles

    Institute of Scientific and Technical Information of China (English)

    WANG Guihua; SU Jilan; LI Rongfeng

    2005-01-01

    Some life history statistics of the mesoscale eddies ofthe South China Sea (SCS) derived from altimetry data will be further discussed according their different formation periods.A total of three ATLAS (autonomous temperature line acquisition system)mooring buoys data will be analyzed to discuss eddies' impact on temperature profiles.They identify that the intraseasonal variation of SCSthermocline is partly controlled by mesoscale eddies.

  13. Observed characteristics of atmospheric ducts over the South China Sea in autumn

    Science.gov (United States)

    Cheng, Yinhe; Zhou, Shengqi; Wang, Dongxiao; Lu, Yuanzheng; Huang, Ke; Yao, Jinglong; You, Xiaobao

    2016-05-01

    The observed characteristics of lower atmospheric ducts over the South China Sea (SCS) were analyzed based on Global Position Systerm (GPS) radiosonde data collected four times daily during autumn open cruises from 2006 to 2012. Duct occurrence, thickness, and strength over the SCS were about 40%, 150-m thick, and 8 M units, respectively, which were larger than during the summer monsoon period. Most ducts occurred at heights military applications.

  14. New Cembrane-Type Diterpenoids from the South China Sea Soft Coral Sarcophyton ehrenbergi

    Directory of Open Access Journals (Sweden)

    Gui-Hua Tang

    2016-05-01

    Full Text Available Chemical investigation on the soft coral Sarcophyton ehrenbergi collected from the Xisha Islands of the South China Sea have led to the isolation of eight cembranoids including five new ones, sarcophytonoxides A–E (1–5. The structures of new cembranoids (1–5 were determined by spectroscopic analysis and comparison of the NMR data with those of related analogues. The cytotoxicities of compounds 1–8 against human ovarian cancer cell line A2780 were also evaluated.

  15. Internal solitons in the northern South China Sea from insitu observations

    Institute of Scientific and Technical Information of China (English)

    FANG Wendong; SHI Ping; LONG Xiaomin; MAO Qingwen

    2005-01-01

    In this paper, we demonstrate the characteris-tics of strong internal solitons at the southern edge of Dong-sha Islands in the northern South China Sea (SCS) during ductivity temperature depth (CTD), acoustic Doppler current profiler (ADCP) and thermistor chain. Our measurements indicated that the strongest internal solitons were larger than 90 m in wave amplitude, and propagated approximately westward in traveling direction, with the maximum current strongest internal solitons occurred noticeably during May the diurnal-dominated spring internal tides.

  16. Stability of submarine slopes in the northern South China Sea: a numerical approach

    Institute of Scientific and Technical Information of China (English)

    ZHANG Liang; LUAN Xiwu

    2013-01-01

    Submarine landslides occur frequently on most continental margins.They are effective mechanisms of sediment transfer but also a geological hazard to seafloor installations.In this paper,submarine slope stability is evaluated using a 2D limit equilibrium method.Considerations of slope,sediment,and triggering force on the factor of safety (FOS) were calculated in drained and undrained (φ=0) cases.Results show that submarine slopes are stable when the slope is <16° under static conditions and without a weak interlayer.With a weak interlayer,slopes are stable at <18° in the drained case and at <9° in the undrained case.Earthquake loading can drastically reduce the shear strength of sediment with increased pore water pressure.The slope became unstable at >13° with earthquake peak ground acceleration (PGA) of 0.5 g;whereas with a weak layer,a PGA of 0.2 g could trigger instability at slopes > 10°,and >3 ° for PGA of 0.5 g.The northern slope of the South China Sea is geomorphologically stable under static conditions.However,because of the possibility of high PGA at the eastern margin of the South China Sea,submarine slides are likely on the Taiwan Bank slope and eastern part of the Dongsha slope.Therefore,submarine slides recognized in seismic profiles on the Taiwan Bank slope would be triggered by an earthquake,the most important factor for triggering submarine slides on the northern slope of the South China Sea.Considering the distribution of PGA,we consider the northern slope of the South China Sea to be stable,excluding the Taiwan Bank slope,which is tectonically active.

  17. Quaternary transgressive and regressive depositional sequences in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Based on the interpretation more than 4000 km sparker single channel seismic profiles and the comparison with Borehole DZQ4 on the outer shelf of the East China Sea (ECS), the seismic sequences, sedimentary facies and paleo-sedimentary environment are studied to establish the chronology framework and discuss the Quaternary transgressive and regressive sequences of the ECS shelf as well as their response to glacio-eustatic sea-level changes. The sea level of the ECS fluctuated with global climate changes in the Quaternary. During the sea level rise, the Pacific tidal wave impacted actively on the ECS continental shelf and the reciprocating tidal currents in NW-SE direction formed tidal sand ridges, which represent large transgressive deposits visible on the seismic profiles. In response to sea level fall, the Yangtze River deltas prograded seaward and built massive subaqueous deltas to form regressive sequences on the seismic profiles. Alternative transgression and regression sequences were vertically distributed on the ECS shelf with the frequent eustacy in the Quaternary. The gentle slope of the ECS shelf makes it possible for the coastline to migrate hundreds of kilometers forth and back on the shelf because of tens of meters sea level changes, in the meanwhile, the Yangtze River discharged large amounts of sediments into the ECS resulting in large-scale subaqueous deltas and tidal sand ridges. There have developed 3 stages of tidal sand ridges and 4 stages of deltas on the ECS shelf since oxygen isotope stage 8.

  18. Species characteristics of lead in sea foods collected from coastal water of Fujian, Southeastern of China

    Science.gov (United States)

    He, Ye; Chen, Zhiqiang; Mo, Fan; Huang, Limei; Xu, Liangjun; Wu, Yongning; Xue, Zhimin; Fu, Fengfu

    2016-09-01

    Various sea foods including fish, shellfish and shrimp were collected from different coastal areas of Fujian in China, and their Pb species characteristics were investigated in detail. The results indicated that there are two different species characteristics of Pb existing in sea food samples. About half of samples were detected to have only Pb2+, and another half of samples were detected to have both Pb2+ and trimethyl lead (TML). The results also revealed that Pb species characteristics in the sea foods rather depend on the species of sea food than the sampling area. In comparison with shellfish/shrimp samples, fish samples have higher concentrations of TML and Pb2+. Especially, the average concentration of TML in the TML-detected fish samples is about 3 times of that in the TML-detected shellfish/shrimp samples, indicating that fish has stronger ability to uptake and accumulate TML. The concentrations of total lead in all samples are lower than the maximum allowable limit of national standard, suggesting that the sea foods collected from Fujian are safe for consumption. By considering that TAL has more toxicity than Pb2+, the effect of TML in sea foods on the human health should be paid more attention in the future.

  19. A continental slope stability evaluation in the Zhujiang River Mouth Basin in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    LIU Ke; WANG Jianhua

    2014-01-01

    In nature, a slope stability is determined by the ratio of a sliding resistance to a slide force. The slide force of a marine deep-water continental slope is mainly affected by sediment mechanics properties, a topography, and a marine seismic. However, the sliding resistance is mainly affected by sedimentary patterns and a sedi-mentary stress history. Both of these are different from case to case, and their impact can be addressed when the data are organized in a geographic information system (GIS). The study area on the continental slope in Zhujiang River Mouth Basin in South China Sea provides an excellent opportunity to apply GIS spatial analysis technology for the evaluation of the slope stability. In this area, a continental slope topography and a three-dimension (3-D) topography mapping show a sea-floor morphology and the distribution of a slope steepness in good detail, and the sediment analysis of seabed samples and an indoor appraisal reveals the variability of a sediment density near the sea-floor surface. On the basis of the results of nine geotechnical studies of submarine study areas, it has worked out that an equivalent cyclic shear stress ratio is roughly between 0.158 and 0.933, which is mainly depending on the initial water content of sediment. A regional density, slope and level of anticipated seismic shaking information are combined in a GIS framework to yield a map that illustrates a continental slope stability zoning under the influencing factors in Zhujiang River Mouth Basin in the South China Sea. The continental slope stability evaluation can contribute to north resources development in the South China Sea, the marine functional zoning, the marine engineering con-struction and adjust measures to local conditions, at the same time also can provide references for other deep-water slope stability analysis.

  20. A reconstruction of late Pleistocene relative sea level in the south Bohai Sea, China, based on sediment grain-size analysis

    Science.gov (United States)

    Yi, Liang; Yu, Hongjun; Ortiz, Joseph D.; Xu, Xingyong; Qiang, Xiaoke; Huang, Haijun; Shi, Xuefa; Deng, Chenglong

    2012-12-01

    Future anthropogenic sea-level rise and its impact on coastal regions is an important issue facing human civilizations. Due to the short nature of the instrumental record of sea-level change, development of proxies for sea-level change prior to the advent of instrumental records is essential to reconstruct long-term background sea-level changes on local, regional and global scales. Here, we employ numerical methods to partition sediment grain size using a combined database of marine surface and core samples, and to quantitatively reconstruct sea-level variation since the late Pleistocene in the south Bohai Sea, China. Our sea-level reconstruction indicates that relative sea-level changes in the southern Bohai Sea track global sea-level variation for the duration of the record. The results also indicate substantial regression from 70 to 30 cal kyr BP, and potentially subarial exposure from 38 to 20 cal kyr BP. Our results document the feasibility of reconstructing relative sea-level change by numerical partitioning of sediment grain size data, demonstrating the potential for future applications.

  1. Physical and underway data collected aboard the MELVILLE during cruise MGLN23MV in the Philippine Sea and South China Sea (Nan Hai) from 2007-07-18 to 2007-07-28 (NODC Accession 0098573)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0098573 includes physical and underway data collected aboard the MELVILLE during cruise MGLN23MV in the Philippine Sea and South China Sea (Nan Hai)...

  2. Physical and underway data collected aboard the MELVILLE during cruise MGLN22MV in the Philippine Sea and South China Sea (Nan Hai) from 2007-07-09 to 2007-07-15 (NODC Accession 0098571)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0098571 includes physical and underway data collected aboard the MELVILLE during cruise MGLN22MV in the Philippine Sea and South China Sea (Nan Hai)...

  3. Physical and underway data collected aboard the ROGER REVELLE during cruise RR1007 in the Philippine Sea and South China Sea (Nan Hai) from 2010-06-01 to 2010-06-10 (NODC Accession 0089637)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089637 includes physical and underway data collected aboard the ROGER REVELLE during cruise RR1007 in the Philippine Sea and South China Sea (Nan...

  4. Physical and underway data collected aboard the ROGER REVELLE during cruise RR1305 in the Philippine Sea and South China Sea (Nan Hai) from 2013-05-07 to 2013-05-16 (NCEI Accession 0132725)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0132725 includes physical and underway data collected aboard the ROGER REVELLE during cruise RR1305 in the Philippine Sea and South China Sea (Nan...

  5. Physical and underway data collected aboard the KILO MOANA during cruise KM0909 in the Philippine Sea and South China Sea (Nan Hai) from 2009-03-20 to 2009-04-09 (NODC Accession 0089676)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089676 includes physical and underway data collected aboard the KILO MOANA during cruise KM0909 in the Philippine Sea and South China Sea (Nan Hai)...

  6. HELIUM, PARTICULATE ORGANIC CARBON and other data from HEIYO, KAIYO and other platforms in the NW Pacific, Philippine Sea and East China Sea from 1939-08-17 to 1988-09-27 (NCEI Accession 9000197)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A tape containing part of the annual exchange of chemical data from the Japan Oceanographic Data Center collected from East China Sea (Tung Hai), Philippine Sea, NW...

  7. Physical and underway data collected aboard the MELVILLE during cruise MV0906 in the Philippine Sea and South China Sea (Nan Hai) from 2009-04-14 to 2009-05-01 (NODC Accession 0089608)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089608 includes physical and underway data collected aboard the MELVILLE during cruise MV0906 in the Philippine Sea and South China Sea (Nan Hai)...

  8. Physical and underway data collected aboard the ROGER REVELLE during cruise RR1104 in the Philippine Sea and South China Sea (Nan Hai) from 2011-03-04 to 2011-03-15 (NCEI Accession 0132120)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0132120 includes physical and underway data collected aboard the ROGER REVELLE during cruise RR1104 in the Philippine Sea and South China Sea (Nan...

  9. Physical and underway data collected aboard the ROGER REVELLE during cruise RR1004 in the Philippine Sea and South China Sea (Nan Hai) from 2010-04-06 to 2010-04-07 (NODC Accession 0089634)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089634 includes physical and underway data collected aboard the ROGER REVELLE during cruise RR1004 in the Philippine Sea and South China Sea (Nan...

  10. Physical and underway data collected aboard the MELVILLE during cruise MGLN38MV in the Philippine Sea and South China Sea (Nan Hai) from 2008-05-04 to 2008-05-14 (NODC Accession 0098581)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0098581 includes physical and underway data collected aboard the MELVILLE during cruise MGLN38MV in the Philippine Sea and South China Sea (Nan Hai)...

  11. Physical and underway data collected aboard the MELVILLE during cruise MV0904 in the Philippine Sea and South China Sea (Nan Hai) from 2009-03-22 to 2009-03-27 (NODC Accession 0089606)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0089606 includes physical and underway data collected aboard the MELVILLE during cruise MV0904 in the Philippine Sea and South China Sea (Nan Hai)...

  12. Physical and underway data collected aboard the MELVILLE during cruise MGLN27MV in the Philippine Sea and South China Sea (Nan Hai) from 2007-10-22 to 2007-11-03 (NODC Accession 0098575)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0098575 includes physical and underway data collected aboard the MELVILLE during cruise MGLN27MV in the Philippine Sea and South China Sea (Nan Hai)...

  13. Physical and underway data collected aboard the MELVILLE during cruise MGLN34MV in the Philippine Sea and South China Sea (Nan Hai) from 2008-03-09 to 2008-03-15 (NCEI Accession 0155969)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0155969 includes physical and underway data collected aboard the MELVILLE during cruise MGLN34MV in the Philippine Sea and South China Sea (Nan Hai)...

  14. Physical and underway data collected aboard the MELVILLE during cruise MGLN35MV in the Philippine Sea and South China Sea (Nan Hai) from 2008-03-23 to 2008-04-02 (NODC Accession 0098580)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC accession 0098580 includes physical and underway data collected aboard the MELVILLE during cruise MGLN35MV in the Philippine Sea and South China Sea (Nan Hai)...

  15. Physical and underway data collected aboard the MELVILLE during cruise MGLN16MV in the Philippine Sea and South China Sea (Nan Hai) from 2007-04-03 to 2007-04-21 (NCEI Accession 0155953)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0155953 includes physical and underway data collected aboard the MELVILLE during cruise MGLN16MV in the Philippine Sea and South China Sea (Nan Hai)...

  16. Physical and profile data collected aboard the ROGER REVELLE during cruise RR1011 in the Philippine Sea and South China Sea (Nan Hai) from 2010-08-14 to 2010-09-11 (NCEI Accession 0134538)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0134538 includes physical and profile data collected aboard the ROGER REVELLE during cruise RR1011 in the Philippine Sea and South China Sea (Nan...

  17. Physical and profile data collected aboard the ROGER REVELLE during cruise RR1307 in the Philippine Sea and South China Sea (Nan Hai) from 2013-05-30 to 2013-06-09 (NCEI Accession 0134539)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0134539 includes physical and profile data collected aboard the ROGER REVELLE during cruise RR1307 in the Philippine Sea and South China Sea (Nan...

  18. Lithospheric Thermal Isostasy of North Continental Margin of the South China Sea

    Institute of Scientific and Technical Information of China (English)

    Chen Shi; Zhang Jian; Sun Yujun; Shi Yaolin

    2009-01-01

    Accompanied with rifting and detaching of the north continental margin of the South China Sea,the ernst and the lithosphere become thinner away from the continental margin resulting from the tectonic activities,such as tensile deformation,thermal uplift,and cooling subsidence,etc..Integrated with thermal,gravimetric,and isostatic analysis techniques,based on the seismic interpretation of the deep penetration seismic soundings across the northern margin of the South China Sea,we reconstructed the lithospheric thermal structure and derived the variation of the crust boundary in the east and west parts of the seismic profde by using gravity anomaly data.We mainly studied the thermal isostasy problems using the bathymetry of the profiles and calculated the crust thinning effect due to the thermal variety in the rifting process.The results Indicate that the thermal isostasy may reach 2.5 kin,and the compositional variations in the ilthospheric density and thickness may produce a variation of 4.0 kin.Therefore,the compositional isostatic correction is very important to recover the relationship between surface heat flow and topography.Moreover,because of the high heat flow characteristic of the continental margin,building the model of lithospheric geotherm in this region is of great importan for studying the Cenozoic tectonic thermal evolution of the north passive continental margin of the South China Sea.

  19. Dynamics of picoplankton in the Nansha Islands area of the South China Sea

    Institute of Scientific and Technical Information of China (English)

    YANGYanhui; JIAONianzhi

    2004-01-01

    Dynamics of major picoplankton groups, Synechococcus (Syn), Prochlorococcus (Pro), picoeukaryotes (Euk) and heterotrophic bacteria (Bact) was investigated by flow cytometry for the first time in the Nansha Islands area in the South China Sea. Averaged over the whole investigation area, depth-weighted integrated cell abundance (DWA) of Syn, Pro, Euk and Bact was 1.6 (0.4-5.7)×103, 5.4(0.1-7.3)×104, 0.7(0.2-2.2)×103, and 2.3 (1.4-3.2)×105 cells/mL respectively. Picoautotrophic cell abundance was low in the northwest part of the Nansha Islands where surface water temperature was low and the upper mixed layer was shallow. Concurrently, a surface maximum vertical distribution pattern was observed in this area. While in the southeast and east zones where temperatures were relatively higher and nitraclines were deeper, picoplankton is abundant and a subsurface maximum around 50-75 m is observed. Coupling of horizontal and vertical distribution patterns of picoplankton abundance and hydrological status was found, suggesting a strong influence of currents and water column structure on picoplankton distribution in the investigation area. Contrary to that in the shelf water in the East China Sea, the relationship between Pro and Bact in the Nansha Islands area in the South China Sea was not significantly negative but weakly positive. Moreover, a similar distribution pattern of Syn and Pro was observed. Possible reasons for these differences in the two marine regimes were discussed.

  20. Molecular approach to the identification of fish in the South China Sea.

    Directory of Open Access Journals (Sweden)

    Junbin Zhang

    Full Text Available BACKGROUND: DNA barcoding is one means of establishing a rapid, accurate, and cost-effective system for the identification of species. It involves the use of short, standard gene targets to create sequence profiles of known species against sequences of unknowns that can be matched and subsequently identified. The Fish Barcode of Life (FISH-BOL campaign has the primary goal of gathering DNA barcode records for all the world's fish species. As a contribution to FISH-BOL, we examined the degree to which DNA barcoding can discriminate marine fishes from the South China Sea. METHODOLOGY/PRINCIPAL FINDINGS: DNA barcodes of cytochrome oxidase subunit I (COI were characterized using 1336 specimens that belong to 242 species fishes from the South China Sea. All specimen provenance data (including digital specimen images and geospatial coordinates of collection localities and collateral sequence information were assembled using Barcode of Life Data System (BOLD; www.barcodinglife.org. Small intraspecific and large interspecific differences create distinct genetic boundaries among most species. In addition, the efficiency of two mitochondrial genes, 16S rRNA (16S and cytochrome b (cytb, and one nuclear ribosomal gene, 18S rRNA (18S, was also evaluated for a few select groups of species. CONCLUSIONS/SIGNIFICANCE: The present study provides evidence for the effectiveness of DNA barcoding as a tool for monitoring marine biodiversity. Open access data of fishes from the South China Sea can benefit relative applications in ecology and taxonomy.

  1. Comparison and validation of global and regional ocean forecasting systems for the South China Sea

    Science.gov (United States)

    Zhu, Xueming; Wang, Hui; Liu, Guimei; Régnier, Charly; Kuang, Xiaodi; Wang, Dakui; Ren, Shihe; Jing, Zhiyou; Drévillon, Marie

    2016-07-01

    In this paper, the performance of two operational ocean forecasting systems, the global Mercator Océan (MO) Operational System, developed and maintained by Mercator Océan in France, and the regional South China Sea Operational Forecasting System (SCSOFS), by the National Marine Environmental Forecasting Center (NMEFC) in China, have been examined. Both systems can provide science-based nowcast/forecast products of temperature, salinity, water level, and ocean circulations. Comparison and validation of the ocean circulations, the structures of temperature and salinity, and some mesoscale activities, such as ocean fronts, typhoons, and mesoscale eddies, are conducted based on observed satellite and in situ data obtained in 2012 in the South China Sea. The results showed that MO performs better in simulating the ocean circulations and sea surface temperature (SST), and SCSOFS performs better in simulating the structures of temperature and salinity. For the mesoscale activities, the performance of SCSOFS is better than MO in simulating SST fronts and SST decrease during Typhoon Tembin compared with the previous studies and satellite data; but model results from both of SCSOFS and MO show some differences from satellite observations. In conclusion, some recommendations have been proposed for both forecast systems to improve their forecasting performance in the near future based on our comparison and validation.

  2. A New Version of Regional Ocean Reanalysis for Coastal Waters of China and Adjacent Seas

    Institute of Scientific and Technical Information of China (English)

    HAN Guijun; LI Wei; ZHANG Xuefeng; WANG Xidong; WU Xinrong; FU Hongli; ZHANG Xiaoshuang

    2013-01-01

    A new regional ocean reanalysis over multiple decades (1958-2008) for the coastal waters of China and adjacent seas has been completed by the National Marine Data and Information Service (NMDIS)under the CORA (China Ocean ReAnalysis) project.Evaluations were performed on three aspects:(1) the improvement of general reanalysis quality; (2) eddy structures; and (3) decadal variability of sea surface height anomalies (SSHAs).Results showed that the quality of the new reanalysis has been enhanced beyond ~40% (39% for temperature,44% for salinity) in terms of the reduction of root mean squared errors (RMSEs) for which the reanalysis values were compared to observed values in the observational space.Compared to the trial version released to public in 2009,the new reanalysis is able to reproduce more detailed eddy structures as seen in satellite and in situ observations.EOF analysis of the reanalysis SSHAs showed that the new reanalysis reconstructs the leading modes of SSHAs much better than the old version.These evaluations suggest that the new CORA regional reanalysis represents a much more useful dataset for the community of the coastal waters of China and adjacent seas.

  3. On tectonic movement in the South China Sea during the Cenozoic

    Institute of Scientific and Technical Information of China (English)

    LIN Changsong; CHU Fengyou; GAO Jinyao; TAN Yonghua

    2009-01-01

    The tectonic movement taking place at the end of Cretaceous and the beginning of Cenozoic had opened the Ce-nozoic phase of polycyclic tectonic movements, then the whole crust of the South China Sea had been mainly subjected to the regional stress field of tectonic tension, which was characterized by rifting depression. Seven times of regional tectonic movement and sedimentation had been assembled into a geological development history of polycyclic oscillation. Especially, the tectonic movements were strongly intensified at the end of Cretacious and the beginning of Paleagene, between Late Eocene and Mid-Oligocene, during Mid- and Late Miocene. These three times of tectonic movement had built the most important regional tectonic interfaces in the South China Sea. Crust movements of the South China Sea were the result and epitome of interaction of the Eurasia, Pacific and Indo-Australia plates, that is, they were introduced by polycyclic changes of directions, rates and strengths of lithospheric movements and asthenospheric flows across the Pacific and Indo-Australia plates.

  4. Preservation of black carbon in the shelf sediments of the East China Sea

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Concentrations and carbon isotopic (14C, 13C) compositions of black carbon (BC) were measured for three sediment cores collected from the Changjiang River estuary and the shelf of the East China Sea. BC concentrations ranged from 0.02 to 0.14 mg/g (dry weight), and accounted for 5% to 26% of the sedimentary total organic carbon (TOC) pool. Among the three sediment cores collected at each site, sediment from the Changjiang River estuary had relatively high BC contents compared with the sediments from the East China Sea shelf, suggesting that the Changjiang River discharge played an important role in the delivery of BC to the coastal region. Radiocarbon measurements indicate that the ages of BC are in the range of 6910 to 12250 years old B.P. (before present), that is in general, 3700 to 9000 years older than the 14C ages of TOC in the sediments. These variable radiocarbon ages suggest that the BC preserved in the sediments was derived from the products of both biomass fire and fossil fuel combustion, as well as from ancient rock weathering. Based on an isotopic mass balance model, we calculated that fossil fuel combustion contributed most (60%―80%) of the BC preserved in these sediments and varied with depth and locations. The deposition and burial of this "slow-cycling" BC in the sediments of the East China Sea shelf represent a significant pool of carbon sink and could greatly in-fluence carbon cycling in the region.

  5. A parabolic model of drag coefficient for storm surge simulation in the South China Sea.

    Science.gov (United States)

    Peng, Shiqiu; Li, Yineng

    2015-10-26

    Drag coefficient (Cd) is an essential metric in the calculation of momentum exchange over the air-sea interface and thus has large impacts on the simulation or forecast of the upper ocean state associated with sea surface winds such as storm surges. Generally, Cd is a function of wind speed. However, the exact relationship between Cd and wind speed is still in dispute, and the widely-used formula that is a linear function of wind speed in an ocean model could lead to large bias at high wind speed. Here we establish a parabolic model of Cd based on storm surge observations and simulation in the South China Sea (SCS) through a number of tropical cyclone cases. Simulation of storm surges for independent Tropical cyclones (TCs) cases indicates that the new parabolic model of Cd outperforms traditional linear models.

  6. Eddy-entrained Pearl River plume into the oligotrophic basin of the South China Sea

    Science.gov (United States)

    He, Xianqiang; Xu, Dongfeng; Bai, Yan; Pan, Delu; Chen, Chen-Tung Arthur; Chen, Xiaoyan; Gong, Fang

    2016-08-01

    The South China Sea (SCS) is the world's largest tropical marginal sea with an oligotrophic basin. In June 2015, a rare large phytoplankton bloom, which is ~500 km long, 100 km wide and lasting more than 19 days, was captured in the northern SCS basin by satellite daily chlorophyll images. Water within the bloom area had a feature of low salinity and high temperature measured by an accidental-passing cruise. Meanwhile, satellite sea level anomaly images and drifter trajectory proved there was a cyclonic eddy nearby. No typhoon and heavy rain happened in this period, so we believed the bloom was triggered by the injection of nutrient-rich Pearl River plume driven by eddy. This is the first report on eddy-entrained Pearl River plume into the SCS, which would raise a new view on irregular transportation of nutrient and carbon and its related biogeochemical influence on the oligotrophic ocean.

  7. Cloudiness regime shift during 1946~1992 recorded by coral in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    By extracting and comparing long-term trend components of coral gray value, sea surface temperature, cloudiness, and net heat flux for the period of 1946~1992, the relationships among them are addressed. There exists a prominent regime shift in the cloudiness associated with the corresponding variabilities of sea surface temperature and net heat flux occurred in the mid-1960s, which can be successfully recorded by coral gray value, a climatic proxy. Long-term cloudiness variations in the South China Sea are completely opposite to the equatorial western Pacific in the past five decades, whereas they share a similar trend to that over Asian monsoon prevailing waters. The fact that the coral gray value is highly correlated to cloudiness provides a unique perspective on utilizing this coral to study cloudiness variations in the pre-instrumental period.

  8. Large scale northward expansion of warm water species Skeletonema tropicum (Bacillariophyceae) in China seas

    Institute of Scientific and Technical Information of China (English)

    LIU Dongyan; JIANG Jinjie; WANG Yan; ZHANG Yong; DI Baoping

    2012-01-01

    Skeletonema tropicum is regarded as a species with an affinity to warm waters and it has never been reported in seas where temperatures drop below 11 ℃ in winter.Previous studies in China reported that S.tropicum was restricted to subtropical and warm temperate seas (East and South China Seas),but the species was recently found during August cruises of 2009 and 2010 in Jiaozhou Bay,Yellow Sea,located several hundred kilometers to the north.Here,winter water temperatures often drop below 5℃.Identification of S.tropicum was confirmed under light and scanning electronic microscopes and maximum cell abundance in Jiaozhou Bay was estimated as 1.73×104cell/L.This record of S.tropicum in Jiaozhou Bay represents a significant northward expansion in the geographic range of the species.Ship ballast water was identified as a possible carrier of S.tropicum from southern places along Chinese coastline,and in addition,thermal pollution from local power stations and seawater desalination plants may provide suitable conditions for species over-wintering.

  9. Spatial diversity of bacterioplankton communities in surface water of northern South China Sea.

    Directory of Open Access Journals (Sweden)

    Jialin Li

    Full Text Available The South China Sea is one of the largest marginal seas, with relatively frequent passage of eddies and featuring distinct spatial variation in the western tropical Pacific Ocean. Here, we report a phylogenetic study of bacterial community structures in surface seawater of the northern South China Sea (nSCS. Samples collected from 31 sites across large environmental gradients were used to construct clone libraries and yielded 2,443 sequences grouped into 170 OTUs. Phylogenetic analysis revealed 23 bacterial classes with major components α-, β- and γ-Proteobacteria, as well as Cyanobacteria. At class and genus taxon levels, community structure of coastal waters was distinctively different from that of deep-sea waters and displayed a higher diversity index. Redundancy analyses revealed that bacterial community structures displayed a significant correlation with the water depth of individual sampling sites. Members of α-Proteobacteria were the principal component contributing to the differences of the clone libraries. Furthermore, the bacterial communities exhibited heterogeneity within zones of upwelling and anticyclonic eddies. Our results suggested that surface bacterial communities in nSCS had two-level patterns of spatial distribution structured by ecological types (coastal VS. oceanic zones and mesoscale physical processes, and also provided evidence for bacterial phylogenetic phyla shaped by ecological preferences.

  10. Four Newly Recorded Free-living Marine Nematodes(Comesomatidae) from the East China Sea

    Institute of Scientific and Technical Information of China (English)

    HUA Er; ZHANG Zhinan

    2007-01-01

    Three species in genus Sabatieria and one in genus Cervonema from the East China Sea were recorded. S. breviseta is characterized by uniformly punctuated coarse dots, large amphids of 5.5 turns (♂) and prominent gubemaculum median piece. The characters of S. breviseta agree quite well with the European original descriptions and only differ in the male amphid tums (5.5 vs.4.0 tums) and unmodified preanal supplements (5-7 vs. 6). S. pulchra can be recognized by amphid 2.75 turns, irregularly arranged lateral dots, and the first three supplements anterior to the anus, which are more widely spaced than the following ones. The excretory system of S. breviseta and S. pulchra shows sexual dimorphism. S. celtica is defined by amphids 2.00-2.25 turns, weakly developed pharyngeal bulb, curved apophyses and 12-13 conspicuous supplements. C. deltensis is characterized by amphids 4.75 tums, ovate pharyngeal posterior bulb, sperm dimorphism, 7 thin preanal supplements, and long tail cylindrical portion (50%-53% of tail length).All the three Sabatieria species are for the first time recorded in Chinese waters. C. deltensis was originally isolated from the Bohai Sea and Yellow Sea and newly recorded in the East China Sea.

  11. Deep crustal structures of eastern China and adjacent seas revealed by magnetic data

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Through reduction to the North Pole and upward continuation of the total field magnetic anomalies, we analyze magnetic patterns and spatial distributions of different tectonic blocks and crustal faults in eastern China and adjacent seas. Depths to the Curie isotherms are further estimated from radially averaged amplitude spectra of magnetic data reduced to the pole. Data reductions effectively enhance boundaries of regional tectonic belts, such as the Dabie ultra-high metamorphic belt, the Tanlu Fault, and the Diaoyudao Uplift. Curie depths are estimated at between 19.6 and 48.9 km, with a mean of 31.7 km. The Subei Basin and the south Yellow Sea Basin in the lower Yangtze block show relatively deep Curie isotherms, up to about 35 km in depth, whereas in the surrounding areas Curie depths are averaged at about 25 km. This implies that the lower Yangtze Block has experienced a unique tectonic evolution and/or has unique basement lithology and structures. From a regional perspective, sedimentary basins, such as the Subei Basin, the south Yellow Sea Basin, and the East China Sea Basin, normally show deeper Curie isotherms than surrounding uplifts such as the Diaoyudao Uplift and the Zhemin Uplifts. Curie isotherms also upwell significantly in volcanically active areas such as the Ryukyu Arc and the Cheju Island, confirming strong magmatic and geothermal activities at depth.

  12. Spatial distribution of Rastrelliger kanagurta (Cuvier 1817) in the South China Sea Exclusive Economic Zone (EEZ)

    Science.gov (United States)

    Razib, N. A.; Mustapha, M. A.

    2013-11-01

    Rastrelliger kanagurta inhabits the South China Sea, where it is the most abundant commercial fish. Understanding distribution of this species is important. Objective of this study is to describe the relationship between spatial distribution of R. kanagurta and its local environmental factors. Chlorophyll-a distribution and sea surface temperature was obtained from Aqua MODIS satellite image. Fisheries data of 2007 to 2010 were obtained from the Southeast Asean Fisheries Department Center (SEAFDEC). These data were analyzed in relation to physical and environmental factors to establish the spatial-temporal distribution of the species. Catch per unit effort (CPUE) was calculated from the fisheries data and used as abundance index. Kernel Density maps of the abundance were created. The result showed that the abundance generated by Kernel Density analysis at 10.0 to 12.0 were associated with chlorophyll-a concentration of 0.4 ± 0.1 mg/m3 and sea surface temperature of 27.0 ± 1.0 °C at offshore of Pahang coast. The density maps showed that the increase of R. kanagurta abundance was occurred in October. The environmental factors in South China Sea played an important role on R. kanagurta's density patterns. This study indicated the capability of GIS and satellite image to indicate aggregation area of R. kanagurta.

  13. Hypoxia in the East China Sea: one of the largest coastal low-oxygen areas in the world

    OpenAIRE

    Chen, Chung-Chi; Gong, Gwo-Ching; Shiah, Fuh-Kwo

    2007-01-01

    Hypoxia in the East China Sea: one of the largest coastal low-oxygen areas in the world correspondence: Corresponding author. Tel.: +886 2 2930 2275; fax: +886 2 2931 2904. (Chen, Chung-Chi) (Chen, Chung-Chi) Deparment of Life Science--> , National Taiwan Normal University--> , 88--> , Sec. 4--> , Ting-Chou Road--> , Taipei 11677--> - TAIWAN, PROVINCE OF CHINA (Chen, Chu...

  14. The Legal Basis of the People’s Republic of China’s East China Sea Air Defense Identification Zone

    OpenAIRE

    Ching Chang

    2016-01-01

    As the People’s Republic of China defined its East China Sea Air Defense Identification Zone (ADIZ) on November 23, 2013, there were three legal decrees, the Law of the People’s Republic of China on National Defense established on March 14, 1997, the Law of the People’s Republic of China on Civil Aviation established on October 30, 1995, and the Basic Rules on Flight of the People’s Republic of China established on July 27, 2001, which have been quoted as the legal basis to define the airspac...

  15. Spring and autumn living coccolithophores in the Bohai Sea and Yellow Sea, China

    Institute of Scientific and Technical Information of China (English)

    JIN Hualong; FENG Yuanyuan; LI Xiaoqian; ZHAI Weidong; SUN Jun

    2015-01-01

    The living coccolithophores (LCs) are an important class of calcified taxa of phytoplankton functional groups, and major producers of marine biogenic inorganic carbon, playing an important role in the marine carbon cycle. In this study, we report the two-demensional abundance, composition of LCs and its correlation with the environmental parameters in spring and autumn, in order to understand the ecological role of LCs in the Yellow Sea and the Bohai Sea. In spring, totally 9 taxa belonging to coccolithophyceae were identified using a polarized microscope at the 1 000× magnification. The dominant species wereEmiliania huxleyi,Gephyrocapsa oceanica, Helicosphaera carteri, andCalcidiscus leptoporus. The abundance of coccosphores and coccoliths ranged 0–7.72 cells/mL, and 0–216.09 coccoliths/mL, with the average values of 0.21 cells/mL, and 11.36 coccoliths/mL, respectively. TheEmiliania huxleyi distribution was similar toGephyrocapsa oceanica. The highest abundance of coccoliths was observed in the east of Shandong Peninsula in northern Yellow Sea, whereasHelicosphaera carteri distributed more widely.Emiliania huxleyi andGephyrocapsa oceanica were the two predominant species in LCs with higher abundances. The distribution of LCs was similar to that of coccoliths. In autumn, 14 taxa belonging to coccolithophyceae were identified with dominant species asEmiliania huxleyi,Gephyrocapsa oceanica, Helicosphaera carteri,Calcidiscus leptoporus andOolithotus fragilis. The abundance of coccosphores and coccoliths ranged 0–24.69 cells/mL, and 0–507.15 coccoliths/mL, with the average values of 1.47 cells/mL, and 55.89 coccoliths/mL, respectively. The highest abundance of coccoliths was located in Qingdao coastal waters and south of the survey area. The distribution of LCs was similar to the coccoliths; in addition, LCs presented large abundance in the east of the central Yellow Sea area.

  16. Estimation of ocean primary productivity and its spatio-temporal variation mechanism for East China Sea based on VGPM model

    Institute of Scientific and Technical Information of China (English)

    LIGuosheng; GAOPing; WANGFang; LIANGQiang

    2004-01-01

    According to calculation results of ocean chlorophyll concentration based on SeaWiFS data by SeaBAM model and synchronous ship-measured data, this research set up an improved model for Case I and Case Ⅱ water bodies respectively. The monthly chlorophyll distribution in the East China Sea in 1998 was obtained from this improved model on calculation results of SeaBAM. The euphotic depth distribution in 1998 in the East China Sea is calculated by using remote sensing data of K490 from SeaWiFS according to the relation between the euphotic depth and the oceanic diffuse attenuation coefficient. With data of ocean chlorophyll concentration, euphotic depth, ocean surface photosynthetic available radiation (PAR), daily photoperiod and optimal rate of daily carbon fixation within a water column, the monthly and annual primary productivity spatio-temporal distributions in the East China Sea in 1998 were obtained based on VGPM model. Based on analysis of those distributions, the conclusion can be drawn that there is a clear bimodality character of primary productivity in the monthly distribution in the East China Sea. In detail, the monthly distribution of primary productivity stays the lowest level in winter and rises rapidly to the peak in spring. It gets down a little in summer, and gets up a little in autumn. The daily average of primary productivity in the whole East China Sea is 560.03 mg/m2/d, which is far higher than the average of subtropical ocean areas. The annual average of primary productivity is 236.95 g/m2/a. The research on the seasonal variety mechanism of primary productivity shows that several factors that affect the spatio-temporal distribution may include the chlorophyll concentration distribution, temperature condition, the Yangtze River diluted water variety, the euphotic depth, ocean current variety, etc. But the main influencing factors may be different in each local sea area.

  17. Bioavailability of dissolved organic carbon linked with the regional carbon cycle in the East China Sea

    Science.gov (United States)

    Gan, Shuchai; Wu, Ying; Zhang, Jing

    2016-02-01

    The regional carbon cycle on continental shelves has created great interest recently due to the enigma of whether these areas are a carbon sink or a source. It is vital for a precise carbon cycle model to take the bioavailability of dissolved organic carbon (DOC) into account, as it impacts the sink and source capacity, especially on dynamic shelves such as the East China Sea. Nine bio-decomposition experiments were carried out to assess differences in the bioavailability of DOC. Samples were collected from different water masses in the East China Sea, such as the Coastal Current, the Taiwan Current, and the Kuroshio Current, as well as from the Changjiang (Yangtze River), the main contributor of terrestrial DOC in the East China Sea. This study aimed to quantify and qualify bioavailable DOC (BDOC) in the East China Sea. Both the degradation constant of BDOC and the carbon output from microorganisms have been quantitatively evaluated. Qualitatively, excitation-emission matrix fluorescence spectra (EEMs) were used to evaluate the intrinsic reasons for BDOC variation. By using EEMs in conjunction with parallel factor analysis (PARAFAC), five individual fluorescent components were identified in this study: three humic-like and two protein-like components (P1, P2). The highest P1 and P2 fluorescence intensities were recorded in the coastal water during a phytoplankton algal bloom, while the lowest intensities were recorded in the Changjiang estuary. Quantitatively, BDOC observed during the incubation ranged from 0 to 26.1 μM. The DOC degradation rate constant varied from 0 to 0.027 (d-1), and was lowest in the Changjiang and highest in algal bloom water and warm shelf water (the Taiwan current). The Taiwan Current and mixed shelf water were the major contributors of BDOC flux to the open ocean, and the East China Sea was a net source of BDOC to the ocean. The results verified the importance of BDOC in regional carbon cycle modeling. Combining the data of BDOC and EEMs

  18. Phytoplankton diversity in the East China Sea and Yellow Sea measured by PCR-DGGE and its relationships with environmental factors

    Institute of Scientific and Technical Information of China (English)

    孙静; 于志刚; 高亚辉; 周茜茜; 甄毓; 陈洪涛; 赵丽媛; 姚庆祯; 米铁柱

    2010-01-01

    Relationships between phytoplankton community composition and environmental variables in the East China Sea (ECS) and Yellow Sea (YS) were investigated using geochemical and molecular microbiology methods. The diversity of phytoplankton was characterized using cultivation-independent PCR-based denaturing gradient gel electrophoresis (DGGE). Groups resulting from unweighted pair-group method with arithmetic averages clustering of the DGGE profiles showed good consistency with the eco-environmental characteri...

  19. Mechanism of formation of low level jets in the South China Sea during spring and summer of 1998

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The mechanism responsible for the formation of the low-level jet (LLJ) over the South China Sea during spring and summer of 1998 was analyzed through using the assimilated grid data provided by the South China Sea monsoon experiment (SCSMEX). More analyses were emphasized on a heavy rainfall process in the Zhujiang Delta area between 8th and 10th June 1998 in which a LLJ played a key role. Furthermore, the MM5 meso-scale model was utilized in studying the effects of the weather systems on the LLJ. The results showed that the kinetic energy associated with the LLJ transferred upward when the LLJ formed, which results in the fact that the big velocity of the LLJ expanded upward to higher level. Simulation verifies that a synoptic-scale low pressure in the low troposphere of the west of South China moved toward the east, with a low-troposphere synoptic-scale high pressure in the western Pacific moving toward the west. In this process, the approach of both systems leads to the reinforcement of pressure gradient force between them, making the kinetic energy needed by the formation of the LLJ increase. Through this process the LLJ formed and developed over the South China Sea between the low and high pressures. Because the formation of the LLJ indicates the enhancement of summer monsoon in the South China Sea, the mechanism responsible for formation of the LLJ could be used in explaining an enhancement of summer monsoon in the South China Sea.

  20. Distributions and sea-to-air fluxes of chloroform, trichloroethylene, tetrachloroethylene, chlorodibromomethane and bromoform in the Yellow Sea and the East China Sea during spring.

    Science.gov (United States)

    He, Zhen; Yang, Gui-Peng; Lu, Xiao-Lan; Zhang, Hong-Hai

    2013-06-01

    Halocarbons including chloroform (CHCl3), trichloroethylene (C2HCl3), tetrachloroethylene (C2Cl4), chlorodibromomethane (CHBr2Cl) and bromoform (CHBr3) were measured in the Yellow Sea (YS) and the East China Sea (ECS) during spring 2011. The influences of chlorophyll a, salinity and nutrients on the distributions of these gases were examined. Elevated levels of these gases in the coastal waters were attributed to anthropogenic inputs and biological release by phytoplankton. The vertical distributions of these gases in the water column were controlled by different source strengths and water masses. Using atmospheric concentrations measured in spring 2012 and seawater concentrations obtained from this study, the sea-to-air fluxes of these gases were estimated. Our results showed that the emissions of C2HCl3, C2Cl4, CHBr2Cl, and CHBr3 from the study area could account for 16.5%, 10.5%, 14.6%, and 3.5% of global oceanic emissions, respectively, indicating that the coastal shelf may contribute significantly to the global oceanic emissions of these gases.

  1. Study on abundance variation of pteropods in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    On the basis of the census in four seasons from 1997 to 2000 in the East China Sea (23°30'~33°N, 118°30'~128°E), the horizontal distribution of pteropods, the seasonal variations of their abundance and dynamic mechanisms of these variations were approached with quantitative and qualitative methods. Results showed that the total abundance of pteropods varied clearly with the seasons in an order of decrease of autumn (108×l0-2 ind./m3), summer (33×10-2 ind./m3), winter(28×10-2 ind./m3) and spring (10×l0-2 ind./m3).Pteropods were not observed in the north nearshore of the East China Sea (29°30'~33°N, 122°30'~125°E)in winter and spring. In all seasons, the peteropod abundance was higher in the south than that in the north and higher in the offshore than that in the nearshore.The major species influencing the peteropod abundance were Creseis acicula in spring, Creseis virgula in summer, Desmopterus papilio in autumn and Limacina trochiformis in winter. The variation ofpteropod abundance showed a prominent linear correlation with the surface water temperature and 10 m water temperature, but no significant correlation with both the bottom water temperature and salinity. In summer, the high-abundance distribution area of pteropods was located in the place where the Taiwan Warm Current branched from the Kuroshio. Inautumn, the distribution area with an abundance higher than 250×10-2ind./m3 expanded northward along with the Taiwan Warm Current within the mixing area where the Changjiang freshwater, the Fujian-Zhejiang coastal water and the Huanghai Sea Cold Water met together. Water temperature and warm currents were the most important environmental factors that influenced the changes ofpteropod abundance in the East China Sea.

  2. Phytoplankton pigment patterns and community composition in the northern South China Sea during winter

    Institute of Scientific and Technical Information of China (English)

    ZHAI Hongchang; NING Xiuren; TANG Xuexi; HAO Qiang; LE Fengfeng; QIAO Jing

    2011-01-01

    Phytoplankton pigment patterns and community composition were investigated in the northern South China Sea using high-performance liquid chromatography and the CHEMTAX software from February 11 to 23, 2009. We recognized four different vertical distribution patterns of pigments: chlorophyll a (Chl a)-like type, divinyl chlorophyll a (DV Chl a) type, even distribution type, and surface type. The average value of ratios of accessory photo-protective pigments (APP) to accessory photo-synthetic pigments was 0.89±0.63 in the upper 50 m and 0.16±0.06 below 50 m depth. With increasing depth, APP decreased and photo-synthetically active radiation was attenuated. There was an obvious succession in the phytoplankton community from inshore to the open sea. Diatoms were dominant in the inshore region, while pelagophytes, Prochlorococcus,cyanobacteria and prymnesiophytes were dominant in the open sea. The vertical distribution of phytoplankton also differed greatly from inshore to the open sea. In the coastal and shelf region,diatoms were important components in the whole water column. Cyanobacteria also had a high abundance at the Subsurface Chlorophyll a Maxima (SCM) in the shelf region. In the slope and open sea, Prochlorococcus and cyanobacteria were important groups above the SCM, while pelagophytes dominated below the SCM.

  3. MANAGING INTRA-REGIONAL CONFLICTS IN SOUTHEAST ASIA. THE CASE OF THE SOUTH CHINA SEA

    Directory of Open Access Journals (Sweden)

    Ioana-Bianca BERNA

    2013-10-01

    Full Text Available This paper is aiming to address the Association of Southeast Asian Nations’ (ASEAN’s management of intra-regional conflicts by integrating the study of the core-source of its current position, comparing and contrasting the different two most significant periods of its existence: the early Post-Cold War Era and its current unveilings, and hedging towards explaining why its barely-enough pragmatism is no longer a solvable demeanor for its survival. The paper will focus on the The South China Sea conflict in the pursuance to explain the distinctions that ASEAN’s management of intra-regional confl icts has gained through experience, through realizing its limited containment capacity as far the regional role of great powers is concerned, or through a critical removal of passivism in the confi dence-winning processes of extra-regional partners. The paper’s choice to address The South China Sea as an intra-regional conflict may be surprising for some, or may inflate others more straightforward as far as the choice for instrumental methods is concerned. In order to better explain this paper’s macro-purposes, the South-China Sea confl ict is an intra-regional confl ict, as the Southeast Asian states involved have divergent claims regarding the sovereignty dilemma. Secondly, more interesting issues might be brought to the table with the involvement of a great power in an intra-regional confl ict. Last but not least, as connected to the previous argument, ASEAN’s engaging and sensitizing of China may generate, from an early start, effects on the perceptionbuilding process between the actors involved.

  4. Air-sea exchange of gaseous mercury in the tropical coast (Luhuitou fringing reef) of the South China Sea, the Hainan Island, China.

    Science.gov (United States)

    Ci, Zhijia; Zhang, Xiaoshan; Wang, Zhangwei

    2016-06-01

    The air-sea exchange of gaseous mercury (mainly Hg(0)) in the tropical ocean is an important part of the global Hg biogeochemical cycle, but the related investigations are limited. In this study, we simultaneously measured Hg(0) concentrations in surface waters and overlaying air in the tropical coast (Luhuitou fringing reef) of the South China Sea (SCS), Hainan Island, China, for 13 days on January-February 2015. The purpose of this study was to explore the temporal variation of Hg(0) concentrations in air and surface waters, estimate the air-sea Hg(0) flux, and reveal their influencing factors in the tropical coastal environment. The mean concentrations (±SD) of Hg(0) in air and total Hg (THg) in waters were 2.34 ± 0.26 ng m(-3) and 1.40 ± 0.48 ng L(-1), respectively. Both Hg(0) concentrations in waters (53.7 ± 18.8 pg L(-1)) and Hg(0)/THg ratios (3.8 %) in this study were significantly higher than those of the open water of the SCS in winter. Hg(0) in waters usually exhibited a clear diurnal variation with increased concentrations in daytime and decreased concentrations in nighttime, especially in cloudless days with low wind speed. Linear regression analysis suggested that Hg(0) concentrations in waters were positively and significantly correlated to the photosynthetically active radiation (PAR) (R (2) = 0.42, p < 0.001). Surface waters were always supersaturated with Hg(0) compared to air (the degree of saturation, 2.46 to 13.87), indicating that the surface water was one of the atmospheric Hg(0) sources. The air-sea Hg(0) fluxes were estimated to be 1.73 ± 1.25 ng m(-2) h(-1) with a large range between 0.01 and 6.06 ng m(-2) h(-1). The high variation of Hg(0) fluxes was mainly attributed to the greatly temporal variation of wind speed. PMID:26931659

  5. Application of a sea surface temperature front composite algorithm in the Bohai, Yellow, and East China Seas

    Science.gov (United States)

    Ping, Bo; Su, Fenzhen; Meng, Yunshan; Du, Yunyan; Fang, Shenghui

    2016-05-01

    The oceanic front is a narrow zone in which water properties change abruptly within a short distance. The sea surface temperature (SST) front is an important type of oceanic front, which plays a signifi cant role in many fi elds including fi sheries, the military, and industry. Satellite-derived SST images have been used widely for front detection, although these data are susceptible to infl uence by many objective factors such as clouds, which can cause missing data and a reduction in front detection accuracy. However, front detection in a single SST image cannot fully refl ect its temporal variability and therefore, the long-term mean frequency of occurrence of SST fronts and their gradients are often used to analyze the variations of fronts over time. In this paper, an SST front composite algorithm is proposed that exploits the frontal average gradient and frequency more eff ectively. Through experiments based on MODIS Terra and Aqua data, we verifi ed that fronts could be distinguished better by using the proposed algorithm. Additionally through its use, we analyzed the monthly variations of fronts in the Bohai, Yellow, and East China Seas, based on Terra data from 2000 to 2013.

  6. The Sea Surface Temperature Variation during the Spring Tide and Neap Tide in the South China Sea

    Science.gov (United States)

    Huang, Shih-Jen; Kuo, Nan-Jung; Ho, Chung-Ru; Lo, Yao-Tsai

    2016-04-01

    The sea surface temperature (SST) data of MODIS/Terra (Moderate-resolution Imaging Spectroradiometer) are used to analyze the SST difference between the spring tide and the neap tide in the South China Sea (SCS) from 2001 to 2013. The 4 stations from north to south in the SCS are used to investigate the variation of SST. The results show the lowest SST found on January and the highest SST found on June. The standard deviation of SST in shallow regions (St. 1 and St. 4) are larger than the deep regions (St. 2 and St. 3). During the winter and spring the standard deviation of SST at the neap tide are greater than the spring tide period. From the later winter to early summer, the SST during the neap tide period is greater than the spring tide period. They are more obvious in the shallow regions. Meanwhile the influence of tide action in the shallow regions is greater than it in the deep regions.

  7. Distribution of dissolved inorganic nitrogen over the continental slope of the Yellow Sea and East China Sea

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xuan; SHI Xiaoyong; WEN Tingting; ZHANG Chuansong; HAN Xiurong

    2013-01-01

    Based on survey data from April to May 2009,distribution and its influential factors of dissolved inorganic nitrogen (DIN) over the continental slopes of the Yellow Sea (YS) and East China Sea (ECS) are discussed.Influenced by the Changjiang (Yangtze) River water,alongshore currents,and the Kuroshio current off the coast,DIN concentrations were higher in the Changjiang River estuary,but lower (<1 μrnol/L) in the northern and eastern YS and outer continental shelf area of the ECS.In the YS,the thermocline formed in spring,and a cold-water mass with higher DIN concentration (about 11 μmol/L)formed in benthonic water around 123.2°E.In Changjiang estuary (around 123°E,32°N),DIN concentration was higher in the 10 m layer; however,the bottom DIN concentration was lower,possibly influenced by mixing of the Taiwan Warm Current and offshore currents.

  8. Planktonic foraminifera and sea surface temperature (SST) of the Xisha Trough, South China Sea since Last Glaciation

    Institute of Scientific and Technical Information of China (English)

    江茂生; 李学杰

    2003-01-01

    The high-resolution analysis on the carbon and oxygen isotopes and planktonic foraminifera of core SA12-19 dated with 14C approach in the Xisha Trough of South China Sea indicates that sediments are attributed to oxygen isotope stages 1-3 (stage 3 is not included completely), during the late-glacial to post-glacial periods. The sea surface temperature (SST) of each sample is calculated based on palaeoecological transfer functions (FP-12E). The results reveal a gradual thermocline increase in this area during oxygen isotope stages 1-3 e.g. a temporal thermocline deepening in the middle Holocene. During the Holocene, the SST was 23.3-27.2℃ in winter, 28.8-29.8℃ in summer. During oxygen isotope stage 2, the SST was 21.4-24.4℃ in winter, 28.1-29.0℃ in summer; and 21.9-25.2℃ in winter, 28.5-29.3℃ in summer during oxygen isotope stage 3. The SST in winter during oxygen isotope stage 2 was 2-6℃ lower than that of stage 3. During the transitional period, a "Younger Dryas Event", standing for a rapid climate return, occurred obviously.

  9. Thermal fronts and cross-frontal heat flux in the southern Huanghai Sea and the East China Sea

    Institute of Scientific and Technical Information of China (English)

    PARK Sunghyea; CHU Peter C

    2008-01-01

    Synoptic features in/around thermal fronts and cross-frontal heat fluxes in the southern Huanghai/Yellow Sea and East China Sea(HES) were examined using the data collected from four airborne expendable bathythermograph surveys with horizontal approxmately 35 km and vertical 1 m( from the surface to 400 m deep) spacings. Since the fronts are strongly affected by HES current system, the synoptic thermal features in/around them represent the interaction of currents with surrounding water masses. These features can not be obtained from climatological data. The identified thermal features are listed as follows: (1) multiple boundaries of cold water, asymmetric thermochne intrusion, locally-split front by homogeneous water of approxmately 18 ℃, and mergence of the front by the Taiwan Warm Current in/around summertime southern Cheju-Changjiang/Yangtze front and Tsushima front; (2) springtime frontal eddy-like feature around Tsnshima front; (3) year-round cyclonic meandering and summertime temperature-inversion at the bottom of the surface mixed layer in Cheju-Tsushima front; and (4) multistructure of Kuroshio front. In the Kureshio front the mean variance of vertical temperature gradient is an order of degree smaller than that in other HES fronts.The southern Cheju-Changjiang front and Cheju-Tsushima front are connected with each other in the summer with comparable cross-frontal temperature gradient. However, cross-frontal heat flux and lateral eddy diffusivity are stronger in the southern Cheju-Changjiang front. The cross-frontal heat exchange is the largest in the mixing zone between the modified Huanghai Sea bottom cold water and the Tsushima Warm Current, which is attributable to enhanced thermocline intrusions.

  10. Clay minerals and geochemistry of the bottom sediments in the northwestern East China Sea

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Clay minerals of 34 sediments collected from the northwestern continental shelf of the East China Sea have been determined by X-ray diffraction analysis. The clay mineral distribution is mainly controlled by the sediment source and the dominant circulation pattern. The predominant clay mineral in our study area is illite comprising more than 67% of the whole clay fraction. The highest concentration of illite (>68%) is found in the southeastern offshore parts beyond the reach of terrigenous input from the Jeju Island. It means that these illites are largely transported by the Kuroshio Current from the South China Sea (SCS). Smectite is highly concentrated in the northwest middle part and in the outer-shelf mud patch. It seems to be due to the high supply of smectite transported from China where fine-grained sediments are discharged from modern and ancient Huanghe (Yellow) River. The relatively high abundant kaolinite is likely derived from the Changjiang (Yangtze) River via the Taiwan Warm Current. In contrast,large amounts of chlorite and high chlorite/kaolinite ratios occur in the northwestern area, reflecting the transportation by the Yellow Sea Coastal Current from the southern Yellow Sea. The discrimination diagrams clearly show that the sediments in the northwestern East China Sea are ultimately sourced from Chinese rivers, especially from the Huanghe River, whereas the sediment in the northeast part might come from the Jeju Island. The muddy sediments of the Changjiang River's submerged delta have much lower 87Sr/86Sr ratios (0.7162-0.7180) than those of the Shandong Peninsular mud wedge (0.7216-0.7249),which are supposed to be originated from the Huanghe River, suggesting the distribution pattern of 87Sr/86Sr ratios as a new tracer to discriminate the provenance of shelf sediments in the study area. The 87Sr/86Sr ratios of the outer-shelf muddy sediments ranged from 0.7169 to 0.7216 in a wide range and was between those of the Huanghe River and Changjiang

  11. Environment and security in the South China Sea region : the role of experts, non-governmental actors and governments in regime building processes

    OpenAIRE

    1999-01-01

    Background: The Spratly islands in the South China Sea are today the focal point of a territorial dispute that represents a serious threat to the regional security in Southeast Asia. Six governments - China, Vietnam, Taiwan, the Philippines, Malaysia and Brunei - have laid claims to all or some of the more than 230 islets, reefs and shoals in the Spratly area. The Peoples Republic of China (PRC) is a key player in the South China Sea conflict. However, the South China Sea is not jus...

  12. Sedimentary ladderane core lipids as potential indicators of hypoxia in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    ZHAO Zongshan; CAO Yali; LI Li; SONG Guodong; YANG Hongmei; LIU Sumei; ZHAO Meixun

    2013-01-01

    Anammox (anaerobic ammonium oxidation) is an important process in many suboxic to anoxic marine environments for converting fixed nitrogen to N2,and has a major impact on the marine nitrogen cycle.Ladderane core lipids have been utilized as an indicator of the contribution of anammox to the marine nitrogen cycles.However,such studies have not been reported for the China seas and little is known about the importance ofanammox within the nitrogen cycle of these marginal seas.In the research reported here,the ladderane core lipid contents of 17 surface sediment samples from the East China Sea are reported,and their spatial distribution is investigated.C1s-[5]-ladderane FAME,C20-[5]-ladderane FAME and C20-[3]-ladderane FAME have all been detected,suggesting that the anammox bacteria are widely present within the study area.The total contents of the three ladderane lipids (ΣFAMEs) range from 24-355 ng/g (weight of dry sediments),with higher contents occurring in the Minzhe Mud Zone and broadly coincident with the spatial distribution of hypoxia.It is suggested that the sedimentary ladderane core lipids are mainly produced in the water column and their sedimentary contents can be used as indicators of water colunm hypoxia.

  13. The Distribution of Dissolved Aluminum in the Yellow and East China Seas

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Water samples containing dissolved aluminum were collected from the Yellow and East China Seas in October-November 2000. The average concentrations of dissolved Al in the Yellow Sea (YS) and East China Sea (ECS) were 0.042 and 0.056 μ molL-1, respectively. The concentration of dissolved aluminum decreased gradually across the continental shelf. The lower concentrations appeared in the YS cold water center and in the bottom layer at the shelf edge of the ECS, where they were 0.016 and 0.011 μmolL-1, respectively. The distribution of dissolved A1 was controlled by physical mixing processes rather than biological uptake processes. The impact of different water masses along the PN transect was calculated based on the mass balance model. The results show that the impact of the Changjiang River was mainly concentrated on the coastal area and the top thermocline water on the ECS shelf, where the impact percentage decreased from 12.6% to 1.1% in the surface water, while the contribution of the Kuroshio water was dominant on the ECS shelf in this survey, increasing from 77.6% to 97.8% along the PN transect from the Changjiang River Estuary to the Ryukyu Islands. It is concluded that aluminum can serve as a proper tracer for studying the impact of Changjiang terrestrial matter on the ECS shelf water.

  14. A Numerical Study of Sea Breeze and Spatiotemporal Variation in the Coastal Atmospheric Boundary Layer at Hainan Island, China

    Science.gov (United States)

    Huang, Qian-Qian; Cai, Xu-Hui; Song, Yu; Kang, Ling

    2016-06-01

    Numerical simulations of sea breezes and the coastal atmospheric boundary layer (ABL) at Hainan Island, China during summer and winter are discussed. The different behaviour of sea breezes and the ABL on the leeward and windward sides of the island are examined, and it is found that offshore flows are more likely to create a strong sea-breeze signature, whereas the process of sea-breeze development under onshore flows is difficult to capture. At the location where the sea-breeze signal is remarkable, the height of the coastal ABL displays an abnormal decrease, corresponding to a transitional point from a continental ABL to a thermal internal boundary layer (TIBL) formed under sea-breeze conditions. This is corroborated by the sudden increase in the water vapour mixing ratio and/or wind speed, indicating the arrival of the sea breeze. Regarding the spatial distribution, the TIBL height decreases abruptly just ahead of the sea-breeze front, and above the cold air mass. When the sea-breeze front occurs with a raised head, a cold air mass is separated from the sea-breeze flow and penetrates inland. This separation is attributed to the interaction between the sea breeze and valley breeze, while the dry airflow entraining to the sea-breeze flow may also partially contribute to this air mass separation.

  15. The Current Situation and Trend in South China Sea%当前南海形势及走向

    Institute of Scientific and Technical Information of China (English)

    吴士存

    2015-01-01

    南海问题的实质是南沙岛礁主权和海域管辖权争议,涉及“五国六方”。近年来,受美国全球战略调整等多重因素的影响,南海问题持续升温,有关争端国不断加大权益声索和实际管控力度,地区局势愈演愈烈。南海是我国国防安全海上屏障、发展制海权的重要战略出海口、经济和能源安全的海上运输要道及未来的能源和资源基地。新阶段,南海局势将继续保持升温态势,因此我国需要从国家总体发展战略全局出发,把握并延长战略机遇期,通盘考虑国际和国内影响因素,长远谋划妥善处理南海问题战略和战术决策,有效化解面临的巨大挑战,确保整体利益最大化。%The essence of the South China Sea issue is the dispute among five states and Chinese Taiwan over the sovereignty of Nansha Islands and jurisdiction of maritime zones in the South China Sea. In recent years,relevant disputants have been intensifying the attempts to bolster their claims and actual control. Regional situation has been moving towards greater tensions. The South China Sea acts as a maritime shield for China to strengthen na_tional defense,an important sea outlet for China to gain sea power,significant sea lanes for China to safeguard e_conomic and energy security,and a base for China to secure energy and other resources in the future. Therefore, it is imperative for China to maintain the maritime rights. In a new historical period when the South China Sea situation continue to intensify,we should approach the South China Sea issue from the standpoint of overall na_tional development strategy,seek important opportunities for strategic development,take international and domes_tic factors into account,develop long_term strategic and tactical countermeasures to alleviate the current situa_tion and maximize China′s interests.

  16. Influence of small river derived sediment on the Northeastern South China Sea sedimentation processes in the last 40 K years

    Science.gov (United States)

    Cheng, Wan-Yen; Lin, Saulwood; Lou, Jiann-Yuh; Wei, Kuo-Yen; Liu, CharShine; Chen, Shing-Li; Wang, Yun-Shuen

    2015-04-01

    Small rivers derived particles are major source of sediment to the ocean in the present time. Small rivers in Taiwan are subjected to fast tectonic activity, high precipitation rate and erosion rate. The combined annual river particle load from small rivers on the Island of Taiwan is higher than that of the Mississippi River. A large fraction of those rivers particle may finding its way into the surrounding seas and ocean, e.g. South China Sea, East China Sea, and the Philippine Sea. Furthermore, due to the nature of particle transportation off rivers from Taiwan were connected by a number of canyon systems close by the river mouth, majority of those river particles were facilitated in delivering and deposited later further into the South China Sea deep basin. The objectives of this study are to understand spatial variations in sedimentation rates and to resolve the temporal differences in sedimentation in the Northeastern South China Sea region, and to evaluate influence of small river particles to the marginal sea. A set of cores was collected in overlying water depth within 1600 - 3300 m for mutilsensor core logging of magnetic susceptibility, density, and porosity. Foraminifera (G. sacculifer, G. conglobatus, O. universa) were picked and AMS C14 analyses for age determination. Grain size, organic carbon, carbonate and biogenic silica content were measured. The results show that large sedimentation rates difference existed in the study area. Earlier studies on sedimentation rate in the region west of our study area were in range of about 10 cm/kyr while our rates are about 20-40 cm/kyr and much higher near Taiwan. Bulk sedimentation rate were higher during the transition period between LGM and Holocene and lower during Holocene. Our results demonstrated that large quantity of particles from small rivers in Taiwan are and were major source of particle and are the dominating factor in controlling sediment deposition in the northeastern South China Sea.

  17. An abrupt cooling event early in the last interglacial in the northern South China Sea

    Institute of Scientific and Technical Information of China (English)

    TU; Xia

    2001-01-01

    [1]Grootes, P. M., Stulver, M., Johnson, J. W. C. et al., Comparison of oxygen isotope records from GISP2 and GRIP Greenland ice cores, Nature, 1993, 366:552-554.[2]Maslin, M., Sarnthein, M., Knaack, J. J. et al., Intra-interglacial cold events: An Eemian-Holocene comparison, The Geo logical Society of London, Special Publications, 1998, 131:91-99.[3]Wang, P., Prell, W., Blum, P. et al., Proceedings of the Ocean Drilling Program, Initial Reports, 2000, 184.[4]Thompson, P. R., Bé, A. W. H., Disappearrence of pink-pigmented Globigerinoides ruber at 120,000yr BP in the Indian and Pacific Oceans, Nature, 1976, 280:554-558.[5]Martinson, D. G., Piasias, N. G., Hays, J. D. et al., Age dating and the orbital theory of the ice ages: Development of a high-resolution 0 to 300000-year chronostratigraphy, Quaternary Research, 1987, 27: 1-29.[6]Thompson, P. R., Planktonic foraminifera in the West North Pacific during the past 150,000 years: Comparison of modern and fossil assemblages, Palaeogeogr. Palaeoclimatol. Palaeoecol., 1981, 35:241-279.[7]Tu, X., Zheng, F., Chen, M. et al., Planktonic foraminifera in continental slope of southern South China Sea and their im plications to paleotemperature of surface sea water, Tropic Oceanology (in Chinese with English abstract), 2000, 19(3): 40-49.[8]Wang, L., Sarnthein, M., Erlenkeuser, H. et al., East Asian monsoon climate during the late Pleistocene: High-resolution sediment records from the South China Sea, Marine Geology, 1999, 156: 245-284.[9]Eglintin, G., Bradshaw, S. A., Rosell, A. et al., Molecular record of secular sea surface temperature changes on 100-year timescales for glacial terminations I, Ⅱ, and IV, Nature, 1992, 356: 423-426.[10]Maslin, M., Sarnthein, M., Knaack, J.-J., Subtropical Eastern Atlantic climate during the Eamian, Naturwissenschaften,1996, 83:122-126.[11]Sarnthein, M., Tiedemann, R., Younger Dryas-style cooling events at glacial terminations I-VI at ODP Site 658

  18. Distribution and Sea-to-air Flux of Nitrous Oxide in the East China Sea during the Summer of 2013

    Science.gov (United States)

    Wang, Lan; Zhang, Guiling; Zhu, Zhuoyi; Li, Jia; Liu, Sumei; Ye, Wangwang; Han, Yu

    2016-07-01

    Dissolved nitrous oxide (N2O) at different depths of 73 stations in the Changjiang (Yangtze River) Estuary and the East China Sea (ECS) were determined from August 4 to 31 of 2013, and the sea-to-air fluxes of N2O were also estimated in this study. N2O concentrations in the surface waters ranged from 6.33 to 44.40 nmol L-1 with an average of (9.27±4.30) nmol L-1 and the values in the bottom waters ranged from 5.19 to 26.98 nmol L-1 with an average of (11.87±3.71) nmol L-1. The concentrations of N2O decreased with distance from the Changjiang Estuary to the open sea. The vertical distributions of N2O indicated great spatial variations. A region of significant bottom-water hypoxia, with oxygen concentration less than 1.5 mg L-1, occurred at the north of the ECS, and increased bottom N2O concentrations was observed. Frequent vertical mixing may enhance the emission of N2O from this hypoxic area. N2O in the surface waters of all stations were over-saturated, and the N2O saturations ranged from 106% to 658%, with an average of (149±62)%. We estimated the sea-to-air fluxes of N2O as (30.6±59.1) μmol m-2 d-1 from the Changjiang Estuary, (9.8±8.8) μmol m-2 d-1 from the coastal and shelf, and (21.0±12.7) μmol m-2 d-1 from the continental slope using the Wanninkhof 1992 equation, (24.9±47.2) μmol m-2 d-1, (8.0±6.7) μmol m-2 d-1 and (16.5±9.6) μmol m-2 d-1 using the Nightingale 2000 equation, respectively. N2O emission from the ECS was estimated to be about (8.2-16.0)×10-2 Tg-N2O yr-1, suggesting that the ECS was a significant net source of atmospheric N2O.

  19. The coral grayness in northern South China Sea and its description of interdecadal variation of precipitation in south China

    Institute of Scientific and Technical Information of China (English)

    GU Dejun; WANG Dongxiao; SUN Donghuai; GAO Rongzhen; JI Zhongping

    2006-01-01

    The interdecadal variation of coral grayness in northern South China Sea (SCS) is studied using the annual mean coral grayness in northern SCS from 1789 to 1992 and annual precipitation at Guangzhou from 1908 to 1992 by Singular Spectrum Analysis (SSA), correlation analysis, Mann-Kendall's abrupt change analysis and composite analysis. The interdecadal variation of south China precipitation as reflected by the series of Guangzhou precipitation rebuilt with the coral grayness is discussed. The results show that the variation of coral grayness in SCS has significant terms of tendency, much-weighted interdecadal variation and weak interannual variation.There was a century-scale abrupt change of coral grayness at the end of the 1880s that changed from positive anomalies to negative anomalies. The global field of SST difference corresponding to the point of abrupt change was negative anomalies over the SCS and neighboring northern Indian Ocean, most of central and western Pacific Ocean and coastal areas of the northern Atlantic Ocean. The large-scale distribution of SST anomalies is concomitant with the century-scale abrupt change of coral grayness in SCS. Negative correlation exists between the coral grayness in SCS and precipitation in Guangzhou on the interdecadal scale and the interdecadal precipitation in Guangzhou as reflected by the interdecadal data of SCS coral grayness shows that the interdecadal variation of south China precipitation changes significantly from phase to phase. The current study aims at contributing in the effort of identifying alternative indexes for climate change in south China on the interdecadal scale and beyond.

  20. Microphysical Characteristics of Sea Fog over the East Coast of Leizhou Peninsula, China

    Institute of Scientific and Technical Information of China (English)

    ZHAO Lijuan; NIU Shengjie; ZHANG Yu; XU Feng

    2013-01-01

    Microphysical properties of sea fog and correlations of these properties were analyzed based on the measurements from a comprehensive field campaign carried out from 15 March to 18 April 2010 on Donghai Island (21°35″N,110°32′5″E) in Zhanjiang,Guangdong Province,China.There were four types of circulation pattern in favor of sea fog events in this area identified,and the synoptic weather pattern was found to influence the microphysical properties of the sea fogs.Those influenced by a warm sector in front of a cold front or the anterior part of low pressure were found to usually have a much longer duration,lower visibility,greater liquid water content,and bigger fog droplet sizes.A fog droplet number concentration of N> 1 cm-3 and liquid water content of L≥0.001 g m-3 can be used to define sea fogs in this area.The type of fog droplet size distribution of the sea fog events was mostly monotonically-decreasing,with the spectrum width always being >20 μ.m.The significant temporal variation of N was due in large part to the number concentration variation of fog droplets with radius <3 μm.A strong collection process appeared when droplet spectrum width was >10 μm,which subsequently led to the sudden increase of droplet spectrum width.The dominant physical process during the sea fog events was activation with subsequent condensational growth or reversible evaporation processes,but turbulent mixing also played an important role.The collection process occurred,but was not vital.

  1. Quaternary transgressive and regressive depositional sequences in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    LIUZhenxia; YINPing; XIONGYingqian; S.Beme; A.Trentesaux; LIChaoxin

    2003-01-01

    Based on the interpretation more than 4000 km sparker single channel seismic profiles and the comparison with Borehole DZQ4 on the outer shelf of the East China Sea (ECS),the seismic sequences,sedimentary facies and paleo-sedimentary environment are studied to establish the chronology framework and discuss the Quaternary transgressive and regressive sequences of the ECS shelf as well as their response to glacio-eustatic sea-level changes.The sea level of the ECS fluctuated with global climate changes in the Quaternary.During the sea level rise,the pacific tidal wave impacted actively on the ECS continental shelf and the reciprocating tidal currents in NW-SE direction formed tidal sand ridges,which represent large transgressive deposits visible on the seismic profiles.In response to sea level fall,the Yangtze River deltas prograded seaward and built massive subaqueous deltas to form regressive sequences on the seismic profiles.Alternative transgression and regression sequences were vertically distributed on the ECS shelf with the frequent eustacy in the Quaternary.The gentle slope of the ECS shelf makes it possible for the coastline to migrate hundreds of kilometers forth and back on the shelf because of tens of meters sea level changes,in the meanwhile,the Yangtze River discharged large amounts of sediments into the ECS resulting in large-scale subaqueous deltas and tidal sand ridges.There have developed 3 stages of tidal sand ridges and 4 stages of deltas on the ECS shelf since oxygen isotope stage 8.

  2. Decadal variability of chlorophyll a in the South China Sea:a possible mechanism

    Institute of Scientific and Technical Information of China (English)

    LIU Fenfen; CHEN Chuqun; ZHAN Haigang

    2012-01-01

    Four climatologies on a monthly scale (January,April,May and November) of chlorophyll a within the South China Sea (SCS) were calculated using a Coastal Zone Color Scanner (CZCS) (1979-1983) and the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) (1998-2002).We analyzed decadal variability of chlorophyll a by comparing the products of the two observation periods.The relationships of variability in chlorophyll a with sea surface wind speed (SSW),sea surface temperature (SST),wind stress (WS),and mixed layer depth (MLD) were determined.The results indicate that there is obvious chlorophyll a decadal variability in the SCS.The decadal chlorophyll a presents distinct seasonal variability in characteristics,which may be as a result of various different dynamic processes.The negative chlorophyll a concentration anomaly in January was associated with the warming of SST and a shallower MLD.Generally,there were higher chlorophyll a concentrations in spring during the SeaWiFS period compared with the CZCS period.However,the chlorophyll a concentration exhibits some regional differences during this season,leading to an explanation being difficult.The deepened MLD may have contributed to the positive chlorophyll a concentration anomalies from the northwestern Luzon Island to the northeastern region of Vietnam during April and May.The increases of chlorophyll a concentration in northwestem Borneo during May may be because the stronger SSW and higher WS produce a deeper mixed layer and convective mixing,leading to high levels of nutrient concentrations.The higher chlorophyll a off southeastem Vietnam may be associated with the advective transport of the colder water extending from the Karimata Strait to southeastem Vietnam.

  3. Influence of the modified global ocean tide model with local tides of East and South China Seas on load gravity in China and its neighbor area

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jiang-cun; SUN He-ping

    2005-01-01

    By using 11 global ocean tide models and tidal gauge data obtained in the East China Sea and South China Sea, the influence of the ocean loading on gravity field in China and its neighbor area is calculated in this paper. Furthermore, the differences between the results from original global models and modified models with local tides are discussed based on above calculation. The comparison shows that the differences at the position near the sea are so large that the local tides must be taken into account in the calculation. When the global ocean tide models of CSR4.0, FES02, GOT00, NAO99 and ORI96 are chosen, the local effect for M2 is less than 0.10×10-8 m·s-2 over the area far away from sea. And the local effect for O1 is less than 0.05 ×10-8 m·s-2 over that area when choosing AG95 or CSR3.0 models. This numerical result demonstrates that the choice of model is a complex problem because of the inconsistent accuracy of the models over the areas of East and South China Seas.

  4. HABs monitor: A tool for detecting HABs in East China Sea

    Directory of Open Access Journals (Sweden)

    Hexia Zhang

    2013-01-01

    Full Text Available This paper designs and develops a tool for detecting HABS from ENVI+IDL+ArcEngine.  With a friendly and artistic interface offered by third party control, this tool provides a function of HABs monitoring in East China Sea via Remote Sensing Images inversion.  Through rows of buttons on the menu bar, this tool allows calculating spectrum reflectance, browsing field work data, interpolating in situ measurement data, retrieving water property parameters, and detecting HABs position by the threshold of chlorophyll-a and sea surface temperature.  Data management module programmed in Structured Query Language (SQL in our tool simplifies the data process and stores a large amount of information.  This paper elaborates the original design, functional modules, and multi data sources that gives a general view toward this tool.

  5. Climate Change and China as a Global Emerging Regulatory Sea Power in the Arctic Ocean

    DEFF Research Database (Denmark)

    Cassotta Pertoldi-Bianchi, Sandra; Hossain, Kamrul; Ren, Jingzheng;

    2015-01-01

    The impact of climate change in the Arctic Ocean such as ice melting and ice retreat facilitates natural resources extraction. Arctic fossil fuel becomes the drivers of geopolitical changes in the Arctic Ocean. Climate change facilitates natural resource extractions and increases competition...... between states and can result in tensions, even military ones. This article investigates through a political and legal analysis the role of China as an emerging regulatory sea power in the Arctic Ocean given its assertive “energy hungry country behaviour” in the Arctic Ocean. The United Nations Convention...... on the Law of the Sea (UNCLOS) and the Arctic Council (AC) are taken into consideration under climate change effects, to assess how global legal frameworks and institutions can deal with China’s strategy in the Arctic Ocean. China’s is moving away from its role as “humble power” to one of “informal...

  6. Paleoceanographic evolution recorded in the northern South China Sea since 4 Ma

    Institute of Scientific and Technical Information of China (English)

    HUANG; Baoqi; JIAN; Zhimin; WANG; Pinxian

    2005-01-01

    Upper water structure over the last 4 million years in the northern South China Sea (SCS) was reconstructed by sea surface temperature (SST) and primary productivity estimated by changes in the abundance of planktonic foraminifer, planktonic foraminifer transfer function, and the accumulation rate of benthic foraminifera. Results of SST and primary productivity show that SST gradually decreased since 4 Ma, but differential seasonal temperature and primary productivity increased in steps mainly at about 3.1, 2.7, 2.1, 1.6, 0.9 and 0.5 Ma. Comparison with tectonics and orbital variations indicates that phased rising of the Tibet since 3.6 Ma, closing of Panama and Indonesian seaways, and orbital changes were responsible for the changes of upper water structure in the SCS, respectively.

  7. Computation of Wave, Tide and Wind Current for the South China Sea Under Tropical Cyclones

    Institute of Scientific and Technical Information of China (English)

    朱良生; 宋运法; 邱章; 陈秀华; 麦波强; 丘耀文; 宋丽莉

    2003-01-01

    Based on the third-generation oceanic wave prediction model (WAVEWATCH Ⅲ),the third-generation nearshore wave calculation model (SWAN) and the mathematical tide, tidal current and cyclone current model, which have been improved, interconnected and expanded, a coupled model of offshore wave, tide and sea current under tropical cyclone surges in the South China Sea has been established. The coupled model is driven by the tropical cyclone field containing the background wind field. In order to test the hindcasting effect of the mathematical model, a comparison has been made between the calculated results and the observational results of waves of 15 cyclone cases, water levels and current velocities of the of 7 cyclones. The results of verification indicate that the calculated and observed results are basically identical.

  8. Responses of thermal structure and vertical dynamic structure of South China Sea to Typhoon Chanchu

    Institute of Scientific and Technical Information of China (English)

    陈宜展; 詹杰民; 罗莹莹; 唐灵; 韦永康

    2014-01-01

    The response of the South China Sea (SCS) to Typhoon Chanchu (2006) was examined using the MM5 and POM model. In the POM model, sea surface boundary conditions were forced by the simulation wind field from MM5, the velocity forcing was introduced in the eastern boundary and the computational schemes of heat fluxes at the surface were introduced. Comparison with the observation data shows that the simulated results are reliable. In the response process of the SCS to Typhoon Chanchu, the influence of the heat fluxes on thermal structure of the SCS was regionally different. Strong wind forcing would lead to upwelling phenomenon in the lateral boundary of deep water basin. Furthermore, the Ekman pumping theory was used to discuss subsurface upwelling and downwelling phenomenon in typhoon forced stage.

  9. Nitrogen deposition fuels harmful algal blooms in the East China Sea

    Science.gov (United States)

    Mackey, K. R.; Kavanaugh, M.; Chien, C. T.; Chen, Y.; Glover, D. M.; Paytan, A.

    2015-12-01

    Chinese marginal seas support vast fisheries and vital economies, but their productivity is threatened by eutrophication and increasing harmful algal blooms (HABs). Here we provide direct experimental evidence that aerosol enrichment shifts seawater chemistry by increasing the ratio of N to phosphorus (N:P) and supports the growth of bloom-forming phytoplankton in the East China Sea. We use a combination of field-based aerosol addition incubation experiments, along with ocean color data on blooms dominated by different taxa to show that HAB forming dinoflagellates are particularly responsive to aerosol inputs. Moreover, we show that the effect of N deposition is strongest in offshore waters further from the Yangtze River outflow, consistent with the large anthropogenic flux of N from this source. This study shows the potential for aerosols to control N:P ratios in offshore waters and to shape the phytoplankton community, contributing to the success of bloom-forming organisms.

  10. CHARACTERISTICS OF FREQUENCY SPECTRUM VARIATION OF INTRASEASONAL OSCILLATION OF CONVECTION DURING SOUTH CHINA SEA SUMMER MONSOON

    Institute of Scientific and Technical Information of China (English)

    LIN Ai-lan; LIANG Jian-yin; LI Chun-hui

    2006-01-01

    Datasets of equivalent temperature of black body (TBB) and sea surface temperature (SST) ranging from 1980 to 1997 are used to diagnose and analyze the characteristics of frequency spectrum and strength of intraseasonal variation of convection. The relationship between the strength of intraseasonal oscillation of convection, strength of convection itself and SST in the South China Sea (SCS) is studied. It is shown that, there are distinguishable annual, interannual and interdecadal variations in both strength and frequency spectrum of intraseasonal variation of convection in SCS. There are connections between strength of convection, strength of ISO1 in the summer half (s.h.) year and SST in ensuing winter half (w.h.) year in SCS.The strong (weak) convection and strong (weak) ISO1 are associated with negative (positive) bias of SST in ensuing w.h. year in SCS.

  11. Cambrian Sequence Stratigraphy and Sea Level Cycles of North China Platform

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The Cambrian of the North China platform consists chiefly of shallow water deposits and shows the sedimentary characters of an epicontinental sea basin. Controlled mainly by global sea level changes and sedimentary influx, the depositional sequences all exhibit as composite sequences. From bottom upward, 14 sequences (3rd order) are recognized, which may be grouped into 5 sequence sets and further into 2 mesosequences (2nd order). It is suggested herein that the Cambrian/Ordovician boundary may better be set at the MFS (maximum flooding surface) of the sequence OSq1, above which the conodont Cordylodus lindstroemi occurs. This position is about 40 m above the traditional Cambrian/Ordovician boundary and is within the Yeli Formation.

  12. Methylmercury in fish from the South China Sea: Geographical distribution and biomagnification

    International Nuclear Information System (INIS)

    Highlights: • A large-scale investigation of MeHg in 46 species of marine wild fish from South China Sea. • Log10 MeHg concentration was significantly related to their length and wet weight. • Feeding habit and habitat were the primary factors influencing MeHg bioaccumulation. • Demersal fish were more likely to be contaminated with MeHg than the epipelagic and mesopelagic species. • Biomagnification of MeHg was site-specific. -- Abstract: We conducted a large-scale investigation of methylmercury (MeHg) in a total of 628 marine wild fish covering 46 different species collected from the South China Sea between 2008 and 2009. Biological and ecological characteristics such as size (length and wet weight), feeding habit, habitat, and stable isotope (δ15N) were examined to explain MeHg bioaccumulation in marine fish and their geographical distribution. MeHg levels in the muscle tissues of the 628 individuals ranged from 0.010 to 1.811 μg/g dry wt. Log10 MeHg concentration was significantly related to their length and wet weight. Feeding habit and habitat were the primary factors influencing MeHg bioaccumulation. Demersal fish were more likely to be contaminated with MeHg than the epipelagic and mesopelagic varieties. Linear relationships were obtained between Log10 (MeHg) and δ15N only for one location, indicating that biomagnification was site-specific. Results from this study suggest that dietary preference and trophic structure were the main factors affecting MeHg bioaccumulation in marine fish from the South China Sea

  13. From orogenic collapse to rifting ; structures of the South China Sea

    Science.gov (United States)

    Pubellier, M.; Chan, L. S.; Chamot Rooke, N.; Shen, W.; Ringenbach, J. C.

    2009-04-01

    The opening of the South China Sea has been a matter of debate for many years because of its internal structure, the differences between the conjugate margins and the variations of rifting and spreading directions. Although it is considered as being a back-arc basin, it is not sitting directly above a subduction zone, and the rifting process lasted for an unusually long duration. Among the specific characteristics is the early phase of rifting which took place early in place of the former Yanshanian andean-type mountain range. This stage is marked by narrow basins filled with deformed conglomerate, and initiated around 70My ago within a framework where the oblique subduction marked by igneous activity and ductile wrench faults, was replaced by orogenic collapse. The rifting stage is marked by Eocene syntectonic normal faults and occasional volcanics centres and has proceeded from NW-SE to NS extension. The NW stretching created at least two aborted basins which remained at rift stage. Extension was followed by spreading from 33 to ~20 Ma in the South China Sea. The ocean floor spreading also changed direction to NW-SE with a propagator inside the Sunda shelf from 20 to 17My ago. However the propagator opening implies that deformation is also taken by rifting around a southern wedge which in turn created strain inside the thinned crust. Another extension parallel to the margin is also observed althought the spreading was in process. The southward motion of the southern conjugate margin was later accommodated by its subduction beneath the NW Borneo wedge until completion of the Proto South China Sea subduction. Variations of rifting spreading through time and variations of structural styles are discussed in terms of boundary forces acting to the SE.

  14. Effects of Kuroshio intrusions on nonlinear internal waves in the South China Sea during winter

    Science.gov (United States)

    Park, Jae-Hun; Farmer, David

    2013-12-01

    During winter the Kuroshio tends to cross Luzon Strait, penetrating the northeastern South China Sea where it forms energetic mesoscale structures. Luzon Strait is also a site where westward-propagating large-amplitude internal waves are generated. We describe observations of these waves acquired in the deep basin of the South China Sea during the winter of 2010-2011, with the goal of assessing the influence of mesoscale variability on their properties. Combining tidal current simulations with an internal wave generation and evolution model, we obtain time series of deviations between our observations and the model simulations. These deviations are analyzed in terms of mesoscale variability based on the data-assimilated HYbrid Coordinate Ocean Model (HYCOM) simulations. We find that simplified models of nonlinear internal wave response to changes in horizontal stratification gradients and vertical shear provide at best weak simulations of amplitude modulation. In contrast to these results, deviations of internal wave arrival time, occurring up to 2 h early during Kuroshio inflows, are quite well simulated when derived from integration of the first internal mode phase speed along two-dimensional ray-traced paths using HYCOM simulations of velocity and density fields together with bathymetry. Refraction of the internal waves by Kuroshio intrusions can lead to substantial distortion of the paths, sufficient to provide a potential explanation for the apparent suppression of waves during previous winter measurements. Our results suggest that the internal wave field can be a sensitive indicator of mesoscale variability in Luzon Strait and the northeastern South China Sea.

  15. Crustal structure and extension mode in the northwestern margin of the South China Sea

    Science.gov (United States)

    Gao, Jinwei; Wu, Shiguo; McIntosh, Kirk; Mi, Lijun; Liu, Zheng; Spence, George

    2016-06-01

    Combining multi-channel seismic reflection and gravity modeling, this study has investigated the crustal structure of the northwestern South China Sea margin. These data constrain a hyper-extended crustal area bounded by basin-bounding faults corresponding to an aborted rift below the Xisha Trough with a subparallel fossil ridge in the adjacent Northwest Sub-basin. The thinnest crust is located in the Xisha Trough, where it is remnant lower crust with a thickness of less than 3 km. Gravity modeling also revealed a hyper-extended crust across the Xisha Trough. The postrift magmatism is well developed and more active in the Xisha Trough and farther southeast than on the northwestern continental margin of the South China Sea; and the magmatic intrusion/extrusion was relatively active during the rifting of Xisha Trough and the Northwest Sub-basin. A narrow continent-ocean transition zone with a width of ˜65 km bounded seaward by a volcanic buried seamount is characterized by crustal thinning, rift depression, low gravity anomaly and the termination of the break-up unconformity seismic reflection. The aborted rift near the continental margin means that there may be no obvious detachment fault like that in the Iberia-Newfoundland type margin. The symmetric rift, extreme hyper-extended continental crust and hotter mantle materials indicate that continental crust underwent stretching phase (pure-shear deformation), thinning phase and breakup followed by onset of seafloor spreading and the mantle-lithosphere may break up before crustal-necking in the northwestern South China Sea margin.

  16. Effects of South China Sea/western North Pacific summer monsoon on tropospheric biennial oscillation (TBO)

    Institute of Scientific and Technical Information of China (English)

    Zheng Bin; Gu De-Jun; Lin Ai-Lan; Li Chun-Hui

    2007-01-01

    Severed theories have been developed to explain tropical biennial oscillation (TBO), as an air-sea interactive system to impact Asian and global weather and climate, and some models have been established to produce a TBO. A simple 5-box model, with almost all the key processes associated with TBO, can produce a TBO by including air-sea interactions in the monsoon regions. Despite that, the South China Sea/western North Pacific summer monsoon (SCS/WNPSM), a very important monsoon subsystem, is neglected. In this paper, based on the dynamical framework of 5-box model, the term of SCS/WNPSM has been added and a 6-box model has been developed. Comparing the difference of TBO sensibilities with several key parameters, air-sea coupling coefficient α, SST-thermocline feedback coefficient γ and wind-evaporation feedback coefficient λ, between the modified model and original model, TBO is more sensible to the parameters in the new model. The results imply that the eastern Pacific and local wind-evaporation play more important roles in the TBO when including SCS/WNPSM.

  17. Distribution of nutrients and eutrophication assessment in the Bohai Sea of China

    Institute of Scientific and Technical Information of China (English)

    WANG Xiulin; CUI Zhengguo; GUO Quan; HAN Xiurong; WANG Jiangtao

    2009-01-01

    Water samples were collected in 120 stations in the Bohai Sea of China to analyze the distribution of dissolved nutrients and assess the degree of eutrophication in August 2002. The result shows that the average concentration of DIN increased and the PO4-P concentration sharply decreased compared to the previous data of corresponding period. The high concentrations of DIN and PO4-P occurred in coastal waters, especially in the bays and some river estuaries, while the high concentrations of SiO3-Si in the surface and middle depth occurred in the central area of the Bohai Sea. The average ratio of DIN/ PO4-P was much higher than the Redfield Ratio (16:1). Apparently, PO4-P was one of the limiting nutrient for phytoplankton growing in the sea. The average concentrations of DON and DOP were higher than their inorganic forms. The results of eutrophication assessment show that 22.1% of all stations were classified as violating the concentration levels of the National Seawater Quality Standard (GB 3097-1997) for DIN and only 3.9% for PO4-P. The average eutrophication index in the overall area was 0.21±0.22 and the high values occurred in Bohai Bay, Liaodong Bay and near the Yellow River estuary. This means that the state of eutrophication was generally mesotrophic in the Bohai Sea, but relatively worse in the bays, especially some river estuaries.

  18. Numerical Simulation of Wintertime Mesoscale Eddies in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    陈敏; 侯一筠; 方国洪

    2003-01-01

    A POM based three-dimension baroclinic prognostic model in σ-coordinate was established to simulate the eddies in the East China Seas wintertime circulation, considering the topography, inflow and outflow on the open boundary, Changjiang runoff, heat, flux, and wind stress on the sea surface. The model results showed that three branches separate from the Kuroshio flow toward the interior of the Yellow Sea, and form three eddies respectively. The middle eddy is centered at 124°37′E,37°00′N,the southern eddy is centered at 124°00′E,35°30′N. The large cyclonic eddy centered at 125°06′E,30°30′N and located southwest of Cheju Island is a closed structure formed by the northeastward flowing Taiwan Warm Current, northwestward flowing Yellow Sea Warm Current and southward flowing coastal current. The Kuroshio intrusion engenders an eddy west of Kyushu Island of Japan. The branching of the Kuroshio is the direct dynamic cause of the formation of this large eddy. Moreover, both the topographic influence and the northward wind prevailing in winter affect the eddy's formation obviously.

  19. Spatial and temporal variation of picoplankton distribution in the Yellow Sea, China

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yuan; ZHAO Li; XIAO Tian; ZHAO Sanjun; XUAN Jiliang; LI Chaolun; NING Xiuren

    2011-01-01

    Seven surveys were carried out in April, September, October, December 2006 and March, May, August 2007 in the Yellow Sea, China. Variations in the spatial and temporal distribution of Synechococcus, picoeukaryotes and heterotrophic bacteria are quantified using flow cytometry. Synechococcus and heterotrophic bacteria are most abundant from late spring to autumn, while picoeukaryotes concentration is high in spring. Synechococcus and heterotrophic bacteria concentrated high in the northwest part of the Yellow Sea in spring and autumn, while picoeukaryotes distributed evenly over the whole study area except for a small frontal zone in the coastal area on the west (in spring) and central Yellow Sea (in autumn). Under mixing conditions, the vertical distribution of the three picoplankton groups showed a well-mixed pattern. Upon a well-established stratification, the maximum abundance of picoplankton occurred above the mixed layer depth (~30 m). Cell sizes of Synechococcus and picoeukaryotes were estimated by converting forward scatter signals (FSC) from cytometry analysis to cell diameter, showing the results of 0.65-0.82 μm for Synechococcus and 0.85-1.08 μm for picoeukaryotes. The average integrated carbon biomasses ranged 15.26-312.62 mgC/m2 for Synechococcus, 18.54-61.57 mgC/m2 for picoeukaryotes, and 402.63-818.46 mgC/m2 for heterotrophic bacteria. The distribution of Synechococcus and heterotrophic bacteria was temperature dependent, and picoplankton presence was poor in the Yellow Sea Cold Water Mass.

  20. The presence of natural radioactivity and 137Cs in the South China Sea bordering peninsular Malaysia.

    Science.gov (United States)

    Amin, Y M; Mahat, R H; Nor, R M; Khandaker, Mayeen Uddin; Takleef, Ghazwa Hatem; Bradley, D A

    2013-10-01

    The presence of natural radioactivity and (137)Cs has been investigated in fresh media obtained from South China Sea locations off the coast of peninsular Malaysia. The media include seafood, sea water and sediment. The samples were collected some weeks prior to the devastating 2011 Tōhoku earthquake and associated tsunami, the occurrence of which precipitated the Fukushima incident. All samples showed the presence of naturally occurring (226)Ra, (228)Ra and primordial (40)K, all at typically prevailing levels. The concentrations of natural radioactivity in molluscs were found to be greater than that of other marine life studied herein, the total activity ranging from 337 to 393 Bq kg(-1) dry weight. The total activity in sea water ranged from 15 to 88 Bq l(-1). Sediment samples obtained at deep sea locations more than 20 km offshore further revealed the presence of (137)Cs. The activity of (137)Cs varied from ND to 0.5 Bq kg(-1) dry weight, the activity increasing with offshore distance and depth. The activity concentrations presented herein should be considered useful in assessing the impact of any future radiological contamination to the marine environment. PMID:23584496

  1. THE INTRUSION AND INFLUENCES OF INTRASEASONAL LONG ROSSBY WAVES IN THE EAST CHINA SEA

    Institute of Scientific and Technical Information of China (English)

    LIN Xiao-pei; WU De-xing; LAN Jian

    2004-01-01

    The analysis of sea level data from tide stations and ocean general circulation model(OGCM)shows that the intraseasonal long Rossby wave results in the intraseasonal variations of Kuroshio axis and transport in the upper reaches of the Kuroshio in the East China Sea(ECS).Due to the transport modulation induced by Ryukyu Islands,the intraseasonal variation is very weak in the lower reaches of the Kuroshio in the ECS.A two-layer model reveals the relation among Kuroshio frontal unstable wave with topography,transport and the axis position of the Kuroshio,from which we can infer that the intrusion of intraseasonal long Rossby wave may stimulate the Kuroshio frontal unstable wave in the upper reaches of the Kuroshio in the ECS.The altimeter data also shows that the sea level anomaly resulting from intraseasonal long Rossby wave could pass the channel between Taiwan and Ryukyu Islands and propagate northeastward in accord with the Kuroshio frontal unstable wave.However,the sea level anomalies passing through the gaps of Ryukyu Islands are relative weak and have negligible effects on the Kuroshio variation.

  2. Impact of atmospheric nitrogen deposition on phytoplankton productivity in the South China Sea

    Science.gov (United States)

    Kim, Tae-Wook; Lee, Kitack; Duce, Robert; Liss, Peter

    2014-05-01

    The impacts of anthropogenic nitrogen (N) deposition on the marine N cycle are only now being revealed, but the magnitudes of those impacts are largely unknown in time and space. The South China Sea (SCS) is particularly subject to high anthropogenic N deposition, because the adjacent countries are highly populated and have rapidly growing economies. Analysis of data sets for atmospheric N deposition, satellite chlorophyll-a (Chl-a), and air mass back trajectories reveals that the transport of N originating from the populated east coasts of China and Indonesia, and its deposition to the ocean, has been responsible for the enhancements of Chl-a in the SCS. We found that atmospheric N deposition contributed approximately 20% of the annual biological new production in the SCS. The airborne contribution of N to new production in the SCS is expected to grow considerably in the coming decades.

  3. Monitoring the burst-out of Enteromorpha prolifera in the Yellow Sea of China

    Science.gov (United States)

    Li, Haiying; Peng, Hongchun; Zhang, Hui; Huang, Chunlin

    2012-10-01

    In the eve of the Beijing Olympics Games, Qingdao in China, as the host city of OSC of Beijing 2008 Olympic Games, was surrounded by Enteromorpha prolifera, which was followed with interest by whole China and the world. The Enteromorpha often comes from other ocean, monitoring the drifting path of the Enteromorpha will become very important.The Study area is mainly the Yellow Sea. And the data sources are Terra MODIS 1B images from 2000-2010 years. The data preprocessing include BOW-TIE processing, image registration, clip, merge, and masking. And the NDVI was selected as the index of derived Enteromorpha prolifera information, to get the range of Enteromorpha prolifera, and get that of dynamic change with time, and monitor the drifting path of the Enteromorpha.

  4. Evidence for a fall raptor migration pathway across the South China Sea

    Science.gov (United States)

    Ellis, D.H.; Kepler, A.K.; Kepler, C.B.

    1990-01-01

    While conducting seabird surveys along the cruise track of the Soviet oceanographic Research Vessel Akademlk Korolev in the South China Sea in late October, 1988, we encountered about 150 land birds, including about 40 raptors. Most of the raptors were small accipiters, but we also recorded small numbers of Peregrine Falcons (Falco peregrinus) and Oriental Scops Owls (Otus sunia). We saw most of the raptors during a 3-day period in a restricted area ca 350 km southeast of the southern tip of the Indo-China Peninsula. The observations suggest that a significant raptor migration corridor exists between Viet Nam and Borneo. The behavior and body condition of the diurnal raptors suggest that they were in good health and were making extensive use of the ship for perching, roosting, and hunting.

  5. Investigation of Spatial and Temporal Trends in Water Quality in Daya Bay, South China Sea

    Directory of Open Access Journals (Sweden)

    Hao Cheng

    2011-06-01

    Full Text Available The objective is to identify the spatial and temporal variability of the hydrochemical quality of the water column in a subtropical coastal system, Daya Bay, China. Water samples were collected in four seasons at 12 monitoring sites. The Southeast Asian monsoons, northeasterly from October to the next April and southwesterly from May to September have also an important influence on water quality in Daya Bay. In the spatial pattern, two groups have been identified, with the help of multidimensional scaling analysis and cluster analysis. Cluster I consisted of the sites S3, S8, S10 and S11 in the west and north coastal parts of Daya Bay. Cluster I is mainly related to anthropogenic activities such as fish-farming. Cluster II consisted of the rest of the stations in the center, east and south parts of Daya Bay. Cluster II is mainly related to seawater exchange from South China Sea.

  6. The Oceanic Crustal Structure of the Southwestern Subbasin in the South China Sea

    Science.gov (United States)

    Wu, Z.; Ruan, A.; Li, J.; Lee, C.

    2012-12-01

    Located at the southwestern part of the South China Sea (SCS) among the Zhongsha Islands(Macclesfield Bank), the east subbasin, the Nansha Islands(Dangerous Ground), the V type southwest subbasin (SWSB) is an unique ocean basin in all the three subbasins of SCS. The crustal structure is one of the key problems to study the formation and evolution of SWSB. During December 2010 to March 2011, Ocean Bottom Seismometers (OBSs) experiment has been carried out in the SWSB to get the deep crustal structure information, especially under the fossil spreading center. Three types of OBS, Sedis IV type, I-4C type and MicrOBS type have been used in the experiment, and the energy source was supplied by 6000 inch3 large volume air-gun. High quality seismic data of four 2D profiles which covered the fossil spreading center of SWSB have been acquired. The data of the experiment can supply evidence for the study of oceanic crustal structure of the SWSB and seafloor spreading course, etc. The profile 1 extended 130 km in length. A total of 8 OBSs were deployed at intervals of 10 or 15 km and 7 OBSs were recovered. The data of the 7 stations of profile 1 have been processed, which shows that the seismic records are clear and seismic phases are abundance, and the air-guns have enough energy supply. The velocity model was obtained by using an interactive trial-and-error 2D ray-tracing method. The crustal structure indicates that the crustal thickness under the SWSB is about 6 km, and the moho depth is about 10km. The results reveal that the crust of SWSB is normal oceanic crust with a thin sedimentary layer on the seamount and shallow moho surface. The crustal velocity under the spreading center is extremely low, which shows the characteristic of the deep crustal structure of the fossil spreading center. Acknowledgements This study was supported by the National Natural Science Foundation of China (Grant No. 91028006, 41106053, 41176046), Scientific Research Fund of the Second Institute

  7. Community structure and biodiversity of free-living marine nematodes in the northern South China Sea

    Institute of Scientific and Technical Information of China (English)

    LIU Xiaoshou; XU Man; ZHANG Jinghuai; LIU Dan; LI Xiao

    2015-01-01

    A quantitative study on the community structure and biodiversity of free-living marine nematodes and their relationship with environmental factors in the northern South China Sea were carried out based on the samples collected at five stations in the deep sea (from 313 to 1 600 m) and one station in shallow waters (87 m) during the cruise in September, 2010. Results showed that the abundance of marine nematodes ranged from 224 to 1 996 ind./(10 cm2). A total of 69 free-living marine nematode genera, belonging to 26 families and three orders, were identified. The most dominant genera wereSabatieria,Linhystera,Aegialoalaimus andDaptonema according to SIMPER analysis. Results of CLUSTER analysis revealed four types of marine nematode community (or station groups) in the sampling area. In terms of trophic structure, non-selective deposit feeders (1B) and selective deposit feeders (1A) were the dominant trophic types with highest genera numbers and abundances, which implied that organic detritus was the main food source of marine nematodes in the northern South China Sea. The percentage of male nematode was low, ranging from 2.22% to 17.81%, while those of juvenile individuals ranged from 36.99% to 82.09%. For genera level diversity of marine nematodes, Shannon-Wiener diversity indices (H') ranged from 3.76 to 4.57 and had highly significant negative correlation with water depth. In general, diversity indicesH' at the five stations in deep sea (over 200 m) were lower than that at the station in shallow waters (87 m). BIOENV analysis showed that the most important environmental factor controlling marine nematode communities was water depth.

  8. Empirical prediction of the onset dates of South China Sea summer monsoon

    Science.gov (United States)

    Zhu, Zhiwei; Li, Tim

    2016-05-01

    The onset of South China Sea summer monsoon (SCSSM) signifies the commencement of the wet season over East Asia. Predicting the SCSSM onset date is of significant importance. In this study, we establish two different statistical models, namely the physical-empirical model (PEM) and the spatial-temporal projection model (STPM) to predict the SCSSM onset. The PEM is constructed from the seasonal prediction perspective. Observational diagnoses reveal that the early onset of the SCSSM is preceded by (a) a warming tendency in middle and lower troposphere (850-500 hPa) over central Siberia from January to March, (b) a La Niña-like zonal dipole sea surface temperature pattern over the tropical Pacific in March, and (c) a dipole sea level pressure pattern with negative center in subtropics and positive center over high latitude of Southern Hemisphere in January. The PEM built on these predictors achieves a cross-validated reforecast temporal correlation coefficient (TCC) skill of 0.84 for the period of 1979-2004, and an independent forecast TCC skill of 0.72 for the period 2005-2014. The STPM is built on the extended-range forecast perspective. Pentad data are used to predict a zonal wind index over the South China Sea region. Similar to PEM, the STPM is constructed using 1979-2004 data. Based on the forecasted zonal wind index, the independent forecast of the SCSSM onset dates achieves a TCC skill of 0.90 for 2005-2014. The STPM provides more detailed information for the intraseasonal evolution during the period of the SCSSM onset (pentad 25-35). The two models proposed herein are expected to facilitate the real-time prediction of the SCSSM onset.

  9. Coral reefs in the South China Sea: Their response to and records on past environmental changes

    Institute of Scientific and Technical Information of China (English)

    YU KeFu

    2012-01-01

    This paper reviews both the recent and longer-term (Holocene) ecological history of coral reefs in the South China Sea (SCS).(1) Local ecological monitoring since the 1960s shows that the coral reefs in the South China Sea have declined dramatically,reflecting the rapid decrease of living coral cover and the great loss of symbiotic zooxanthellae.Collectively,this has led to a significant decrease of annual CaCO3 production.Heavy anthropogenic activities and global warming are recognized as major triggers of the observed coral reef degradation.Observations show that the modern coral reefs in the SCS are a source of atmospheric CO2 in summer.(2) Coral reefs of the SCS have been widely used to reveal longer-term environmental variations,including Holocene high-resolution sea surface temperature (SST) and abrupt climate events,millennial-scale E1 Ni(n)o variations,millennial-and centennial-scale sea level oscillations,strong and cyclic storm activities,East Asian monsoon intensities,variation in seawater pH,and recent seawater pollution,(3) Coral reefs of the southern SCS have experienced repeated episodes of bleaching over the last 200 years due to high SST and intense E1 Ni(n)o events; coral reefs of the northern SCS suffered high levels of mortality during several abrupt winter cold-water bleaching events during the middle Holocene warm period.On average,recovery after the middle Holocene cold-bleaching took 20-30 years; recovery following other middle Holocene environmental stresses took approximately 1020 years.Such findings have significantly contributed to the understanding of the present ecological pressures faced by the coral reefs in the SCS,the histories of Holocene climate/environment changes,and the long-term models of coral reef responses to various past environmental changes.

  10. New record of Lobophora rosacea (Dictyotales; Phaeophyceae) from the South China Sea

    Science.gov (United States)

    Sun, Zhongmin; Wang, Yongqiang; Yan, Pengcheng; Guo, Hui; Yao, Jianting; Tanaka, Jiro; Kawai, Hiroshi

    2016-04-01

    Lobophora rosacea C.W. Vieira, Payri et De Clerck is reported from the South China Sea for the first time. Our specimens are very similar to L. rosacea recently described from New Caledonia, not only in morphology but also in rbcL and cox3 gene sequences. The fan-shaped thallus grows erectly, attaching to the substrate by a basal holdfast. The thallus is composed of a single layer of large medullary cells and three to four layers of cortical cells on both sides of the medulla. Mature sporophytes are detected, with sporangium sori scattered on both surfaces of the thallus.

  11. Implications of IODP Expedition 349 Age Results for the Spreading History of the South China Sea

    Science.gov (United States)

    Briais, Anne

    2016-04-01

    The International Ocean Discovery Program (IODP) Expedition 349 in the South China Sea drilled three sites (U1431, U1433, and U1434) into the basaltic crustal basement near the fossil spreading center in the East and Southwest Subbasins. These results provided age constraints on the termination of seafloor spreading in the South China Sea (SCS) basin. Shipboard biostratigraphic analysis of microfossils from the sediment immediately above or between flows in the basaltic basement indicates early Miocene ages: 16.7-17.6 Ma for Site U1431 in the East Subbasin, ~18-21 Ma for Site U1433 in the Southwest Subbasin. Since Expedition 349, Ar/Ar dating of basalt samples from these two sites have confirmed these ages in the east, and have provided an age of 17 Ma in the Southwest. The similarity in crustal age between sites suggests that the last stages of spreading have been coeaval in both the East and Southwest Subbasins, forming a single mid-ocean ridge system with a series of transform faults and discontinuities between the two subbasins. Expedition 349 also drilled Site U1435 on a bathymetric high along the northwestern continent-ocean boundary. Onboard core description, biostratigraphy and magnetostratigraphy revealed that sediment at this site shows a sharp discontinuity at about 33 Ma, interpreted to represent the breakup unconformity and date the beginning of seafloor spreading in the East Subbasin. The results of IODP Exp. 349, as well as results from deep-towed magnetic surveys, thus imply that oceanic seafloor spreading in the SCS, from 33 to ~16-18 Ma, is coeval with a large part of the left-lateral motion along the Ailao Shan-Red River Fault Zone (dated 34 to 17 Ma). This episode of the extension of the South China Sea basin is therefore more likely driven by the extrusion of the Indochina tectonic block resulting from the collision of India with Eurasia than by the subduction of a proto-South China Sea to the south.

  12. Distribution of the East China Sea continental shelf basins and depths of magnetic sources

    OpenAIRE

    Lin, Jing-yi; Sibuet, Jean-claude; Hsu, S.

    2005-01-01

    The acoustic basement map of the East China Sea, established by the Shanghai Offshore Petroleum Bureau with all available industry seismic data, shows the existence of a 30-km-wide, 10-km-deep basin, that we named the Ho Basin. The Ho Basin belongs to a series of elongated deep basins extending over 600 km east of the Taiwan-Sinzi Ridge and flanked to the East by a ridge named the Longwan Ridge in its northern part. This new system of basin and ridge was probably formed during middle Miocene,...

  13. NUMERICAL STUDY ON THE FORMATION OF THE SOUTH CHINA SEA WARM CURRENT I. BAROTROPIC CASE

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In this work, Princeton Ocean Model (POM) was used to study the formation of the South China Sea Warm Current (SCSWC) in the barotropic case. Monthly averaged wind stress and the inflow/outflow transports in January were used in the numerical simulation which reproduced the SCSWC. The effects of wind stress and inflow/outflow were studied separately. Numerical experiments showed that the Kuroshio intrusion through the Luzon Strait and the slope shelf in the northern SCS are necessary conditions for the formation of the SCSWC. In a flat bottom topography experiment, the wind stress driven northeast current in the northern SCS is a compensatory current.

  14. Cembranoid, Steroid, and Sesquiterpenoid Derivatives from the South China Sea Soft Coral Sinularia numerosa

    Institute of Scientific and Technical Information of China (English)

    秦铭俐; 李晓明; 王斌贵

    2012-01-01

    Two new cembranoids, namely, sinumerolides A and B (1 and 2), one new steroid, 7fl-hydroxygorgosterol (7), along with four known cembranoid derivatives (3-6), four known steroids (8-11), and four known africane ses- quiterpenoids (12-15), were isolated and identified from the marine soil coral Sinularia numerosa that was col- lected from South China Sea waters. The structures of these metabolites were elucidated on the basis of extensive spectroscopic analysis and by comparison of their spectral data with those of literature reports. The isolated com- pounds were evaluated for the antimicrobial and cytotoxic activity.

  15. Analysis of ERS-2 scatterometer winds and wind-wave calculation for eastern China seas

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The wind system over the China seas plays an important role in climate variation there. In this paper, ERS-2 scatterometer winds covering the period of 1998 and the area of 25-41°N, 117-130°E were analyzed and compared to NCEP winds and buoy winds in the same period and location, to assess how well the ERS-2 data reflect the real wind regime, at least for this area. The results indicated that ERS-2 scatterometer winds are closer to buoy observations than NCEP winds. In addition, a new wind-wave growth relation was applied to calculate wave parameters.

  16. Bioactive Cembranoids from the South China Sea Soft Coral Sarcophyton elegans

    Directory of Open Access Journals (Sweden)

    Xin Liu

    2015-07-01

    Full Text Available Four new cembranoids, sarcophelegans A–D (1–4 and six known analogues (5–10 were isolated from the South China Sea soft coral Sarcophyton elegans. Their structures were elucidated through detailed spectroscopic analysis, and the absolute configuration of 1 was confirmed by single-crystal X-ray diffraction. The antimigratory potential of compounds 1–10 were evaluated and compounds 2 and 6 were found to inhibit human breast tumor MDA-MB-231 cell migration at 10 μM.

  17. Alkaloids and Sesquiterpenes from the South China Sea Gorgonian Echinogorgia pseudossapo

    Directory of Open Access Journals (Sweden)

    Shu-Hua Qi

    2011-11-01

    Full Text Available Five zoanthoxanthin alkaloids (1–5 and four sesquiterpenes (6–9 were isolated from the South China Sea gorgonian Echinogorgia pseudossapo. Their structures were determined on the bases of extensive spectroscopic analyses, including 1D and 2D NMR data. Among them, pseudozoanthoxanthins III and IV (1–2, 8-hydroxy-6β-methoxy-14-oxooplop-6,12-olide (6 and 3β-methoxyguaian-10(14-en-2β-ol (7 were new, 1 and 3 showed mild anti-HSV-1 activity, and 7 showed significant antilarval activity towards Balanus amphitrite larvae.

  18. Briarane Diterpenes from the South China Sea Gorgonian Coral, Junceella gemmacea

    Directory of Open Access Journals (Sweden)

    Wei Zhou

    2014-01-01

    Full Text Available Four new briarane diterpenoids, junceellolides M–P (1–4, were isolated together with seven known analogs (5–11 from the South China Sea gorgonian, Junceella gemmacea. The structures of these compounds were elucidated by detailed spectroscopic analysis and comparison with the reported data. The absolute configuration of compounds 1–3 were determined based on an ECD experiment, while the absolute configuration of compound 4 was genetically determined. All the compounds were isolated for the first time from J. gemmacea. These compounds showed no growth inhibitory activity against A549, MG63 and SMMC-7721 cell lines in an in vitro bioassay.

  19. Offshore Wind Resources Assessment from Multiple Satellite Data and WRF Modeling over South China Sea

    DEFF Research Database (Denmark)

    Chang, Rui; Rong, Zhu; Badger, Merete;

    2015-01-01

    offshore winds which can be used for offshore wind resource assessment. First, wind speeds retrieved from Synthetic Aperture Radar (SAR) and Scatterometer ASCAT images were validated against in situ measurements from seven coastal meteorological stations in South China Sea (SCS). The wind roses from....... Meanwhile, the validation of satellite winds against the same co-located mast observations shows a satisfactory level of accuracy which was similar for SAR and ASCAT winds. These satellite winds are then assimilated into the Weather Research and Forecasting (WRF) Model by WRF Data Assimilation (WRFDA...

  20. Bioactive Pregnane Steroids from a South China Sea Gorgonian Carijoa sp.

    OpenAIRE

    2013-01-01

    A new pregnane steroid, 1, and three known analogues 2–4, have been isolated from a gorgonian Carijoa sp. collected from the South China Sea. The planar structure and relative configuration of 1 were elucidated from comprehensive spectroscopic data. Its absolute configuration was determined by application of the modified Mosher method. Compounds 1, 3 and 4 exhibited cytotoxicity against the human hepatoma cell line Bel-7402, with IC50 values of 9.33, 11.02 and 18.68 µM, respectively. Addition...

  1. Multi-scale variability of subsurface temperature in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    高荣珍; 周发琇; 王东晓

    2002-01-01

    Using Morlet wavelet transform and harmonic analysis the multi-scale variability of subsurface temperature in the South China Sea is studied by analyzing one-year (from April 1998 to April 1999) ATLAS mooring data. By wavelet transform, annual and semi-annual cycle as well as intraseasonal variations are found, with different dominance, in subsurface temperature. For annual harmonic cycle, both the downward net surface heat flux and thermocline vertical movement partially control the subsurface temperature variability. For semi-annual cycle and intraseasonal variability, the subsurface temperature variability is mainly linked to the vertical displacement of thermocline.

  2. Intraseasonal variability of the subsurface temperature observed in the South China Sea (SCS)

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Using Morlet wavelet transform we investigated the intraseasonal variability of the subsurface temperature in the SCS by analyzing ATLAS mooring data obtained during the South China Sea Monsoon Experiment (SCSMEX). It is found for the first time that subsurface temperature in the SCS exists intraseasonal variability, particularly in winter. The strongest intraseasonal variability ranges from 50 to 100 m with its maximum amplitude about 1.0--2.0℃. The subsurface temperature intraseasonal variability in the SCS is primarily induced by local wind stress curl via adjusting the vertical displacement of thermocline. It reveals the important characteristic of intraseasonal variations in the SCS upper ocean vertically.

  3. Chemical constituents of soft coral Sarcophyton infundibuliforme from the South China Sea

    KAUST Repository

    Wang, Chang Yun

    2011-08-01

    Chemical investigation on soft coral Sarcophyton infundibuliforme collected from the South China Sea led to the isolation and identification of 14 secondary metabolites, including ten cembrene diterpenoids (1-10), one α-tocopheryl quinone derivative (11), one prostaglandin (12), one lipid (13) and one carotinoid (14). Their structures were determined by extensive analysis of their spectroscopic data. All of these metabolites were isolated from this species for the first time. Diterpenoids 1, 2, 7 and 10 showed potent antifouling activity against the larval settlement of barnacle Balanus amphitrite. © 2011 Elsevier Ltd.

  4. Carbamate derivatives and sesquiterpenoids from the South China Sea gorgonian Melitodes squamata

    OpenAIRE

    Huang, Li-Si; He, Fei; Huang, Hui; Zhang, Xiao-yong; Qi, Shu-Hua

    2012-01-01

    Five carbamate derivatives, obtucarbamates C and D (1, 2), dimethyl ((carbonylbis(azanediyl))bis(2-methyl-5,1-phenylene))dicarbamate (3), obtucarbamates A and B (4, 5), and four aromadendrane-type sesquiterpenoids, (+)-4β-N-methenetauryl-10β-methoxy-1β,5α,6β,7β-aromadendrane (6), (−)-4β-N-methenetauryl-10β-methoxy-1β,5β,6α,7α-aromadendrane (7), (−)-4α,10β-aromadendranediol (8), (+)-4β,10β-aromadendranediol (9) were obtained from the South China Sea gorgonian coral Melitodes squamata Nutting. ...

  5. A new species of Eunice (Polychaeta: Eunicidae) from Hainan Island, South China Sea

    Institute of Scientific and Technical Information of China (English)

    WU Xuwen; SUN Ruiping; LIU Ruiyu(J.Y LIU)

    2013-01-01

    Ataxonomic survey ofbenthic marine animals from coastal regions of Hainan Island,South China Sea,revealed specimens of a new species ofEunice (Polychaeta:Eunicida:Eunicidae),Eunice uschakovi n.sp.,collected from the intertidal zone.The species belongs to the group of Eunice that has yellow tridentate subacicular hooks and branchiae scattered over an extensive region of the body.It resembles E.miurai and E.havaica in having both bidentate and tridentate falcigers,but can be readily distinguished by branchial features.Comparisons between E.uschakovi and the two related species are presented.

  6. New Casbane Diterpenoids from a South China Sea Soft Coral, Sinularia sp.

    Directory of Open Access Journals (Sweden)

    Xinxiang Lei

    2013-02-01

    Full Text Available Six new casbane diterpenoids, named as sinularcasbanes A–F (1–6, along with six known analogues 7–12, were isolated from a South China Sea soft coral, Sinularia sp. The structures of the new compounds were elucidated by extensive spectroscopic analysis and by comparison with data reported in the literature. All compounds were evaluated for their cytotoxicity against selected cancer cell lines and the inhibition of lipopolysaccharide (LPS-induced nitric oxide (NO production in mouse peritoneal macrophages.

  7. BEHAVIOR OF THE CHANGJIANG DILUTED WATER IN THE EAST CHINA SEA OBSERVED WITH SATELLITE TRACKING DRIFTER

    Directory of Open Access Journals (Sweden)

    Syful Anas

    2012-11-01

    Full Text Available The Changjiang River is the largest river in China with an average discharge of 9x1011 m3 /year . The Changjiang river supplies about 80% of total discharge of fresh water from rivers around the Yellow Sea, East China Sea and Bohai Sea. Its monthly mean transport has a large seasonal variation from 103 m3s-1 in January to 4.8x 104 m3s-1 in July around an annual mean of 3 x104 m3s-1 , and large inter annual variation in the annual mean from 2,2x 103 to 3,5 x 103 m3s-1 during the 19-year period from 1970 to 1988 (Yanagi, 1994 . The East China Sea Current, associated with the Changjiang discharge, flows southward along the Fujian and the Zhejiang Coast of China in winter and Northeastward to the Cheju island in summer, which forms thin low salinity plume called Changjiang Diluted Water (CDW in summer (Breadsley. et al , 1983, 1985; Hu, 1994, Guan ,1994.CDW moves differently in season. It moves southward in winter and eastward in summer according to its salinity distribution. The relation between wind and movement of the low salinity water also has been suggested in many ways.Generally all of drifter moved northeastward at first, then after 10 days each drifter moved to different sites. Each drifter moving though velocities is about 0.1 m/s and 0.2 m/s. Most of drifters were generally moving to northeastward to the right of the wind direction at these events. It indicates that the sudden changes of drifters trajectory are caused by abrupt changes of winds.Temporal variation in salinity gradually increase during the drifters were in the moved eastward . The salinity rapidly increase during the typhoon passage. Before and after the salinity rapidly increase during typhoon passage, it was mostly constant or very gentle.The vertical velocity generated by wind just after deployment drifters for ten days in drifter deployment in 2007 was about 10-5 – 10-6 ms-1. The vertical velocity during typhoon passage on August 2007 was larger than on passed the

  8. Anaerobic ammonium oxidation, denitrification and dissimilatory nitrate reduction to ammonium in the East China Sea sediment

    Directory of Open Access Journals (Sweden)

    G. D. Song

    2013-03-01

    Full Text Available Benthic nitrogen transformation pathways were investigated in the sediment of the East China Sea in June of 2010 using the 15N isotope pairing technique. Slurry incubations indicated that denitrification, anammox and dissimilatory nitrate reduction to ammonium (DNRA as well as nitrate release by nitrate storing organisms occurred in the East China Sea sediments. These four processes did not exist independently, the nitrate release therefore diluted the 15N labeling fraction of NO3−, a part of the 15NH4+ derived from DNRA also formed 30N2 via anammox. Therefore current methods of rate calculations led to over and underestimations of anammox and denitrification respectively. Following the procedure outlined in Thampdrup and Dalsgaard (2002, denitrification rates were slightly underestimated by on average 6% without regard to the effect of nitrate release, while this underestimation could be counteracted by the presence of DNRA. On the contrary, anammox rates calculated from 15NO3− experiment were significantly overestimated by 42% without considering nitrate release. In our study this overestimation could only be compensated 14% by taking DNRA into consideration. In a parallel experiment amended with 15NH4+ + 14NO3−, anammox rates were not significantly influenced by DNRA due to the high background of 15NH4+ addition. Excluding measurements in which bioirrigation was present, integrated denitrification rates decreased from 10 to 4 mmol N m−2 d−1 with water depth, while integrated anammox rates increased from 1.5 to 4.0 mmol N m−2 d−1. Consequently, the relative contribution of anammox to the total N-loss increased from 13% at the shallowest site near the Changjiang estuary to 50% at the deepest site on the outer shelf. This study represents the first time in which anammox has been demonstrated to play a significant role in benthic nitrogen cycling in the East China Sea sediment, especially on the outer shelf. N

  9. Air-sea heat flux exchange over the South China Sea under different weather conditions before and after southwest monsoon onset in 2000

    Institute of Scientific and Technical Information of China (English)

    Junyue Yan; Huadong Yao; Jianglong Li; Zhiyi Tang; Guorong Jiang; Wenyu Sha; Xunqiang Li; Yiguo Xiao

    2003-01-01

    With the data observed from the Second SCS Air-Sea Flux Experiment on the Xisha air-sea flux research tower, the radiation budget, latent, sensible heat fluxes and net oceanic heat budgetswere caculated before and after summer monsoon onset. It is discovered that, after summer monsoononset, there are considerable changes in air-sea fluxes, especially in latent heat fluxes and net oceanicheat budget. Furthermre, the analyzed results of five synoptic stages are compared. And the character-istics of the flux transfer during different stages around onset of South China Sea monsoon are discussed.The flux change shows that there is an oceanic heat accumulating process during the pre-onset and thebreak period, as same as oceanic heat losing process during the onset period. Moreover, latent fluxes,the water vapor moving to the continent, even the rainfall appearance in Chinese Mainland also can beinfluenced by southwester. Comparing Xisha fluxes with those obtained from the Indian Ocean and thewestern Pacific Ocean, their differences may be obeerved. It is the reason why SSTs can keep stableover the South China Sea while they decrease quickly over the Arabian Sea and the Bay of Bengal aftermonsoon onset.

  10. Sea surface height and transport stream function of the South China Sea from a variable-grid global ocean circulation model

    Institute of Scientific and Technical Information of China (English)

    魏泽勋; 方国洪; 崔秉昊; 方越; 何宜军

    2003-01-01

    A fine-grid model (1/6°) covering the South China Sea (SCS), East China Sea and Japan/East Sea, which is embedded into a coarse-grid (3°) global model, was established to study the SCS circulation. In the present paper, we report the model-produced monthly and annual mean transport stream functions and sea surface heights(SSH) and their anomalies of the SCS. Comparison to the TOPEX/Poseidon data shows that the model-produced monthly sea surface height anomalies (SSHA) are in good agreement with altimeter measurements. Based on the results, the circulation of the SCS, especially the upper layer circulation, is discussed. In the surface layer, the western Philippine Sea water intrudes into the SCS through the Luzon Strait in autumn, winter and spring, but not in summer. However, as far as the whole water column is concerned, the water intrudes into the SCS through the Luzon Strait all the year round. This indicates that in summer the water still intrudes into the SCS in the subsurface and intermediate layers. The area near the northern continental slope of the SCS is dominated by a cyclonic circulation all the year round. The SCS Southern Anticyclonic Gyre, SE Vietnam Off-Shore Current in summertime and SCS Southern Cyclonic Gyre in wintertime are reproduced reasonably. The difference between the monthly averaged SSH and SSHA is significant, indicating the importance of the mean SSH in the SCS circulation.

  11. Coupled Modes of Rainfall over China and the Pacific Sea Surface Temperature in Boreal Summertime

    Institute of Scientific and Technical Information of China (English)

    LI Chun; MA Hao

    2011-01-01

    In this study,monthly NCEP/NCAR reanalysis data and NOAA ERSST as well as observed precipitation data from 160 stations in China were used to investigate coupled modes affecting the rainfall over China and sea surface temperature (SST) in the Pacific during boreal summertime based on singular value decomposition (SVD) method.The SVD analysis revealed three remarkable coupled modes:rainfall over North China associated with an ENSO-like SST pattern (ENSO NC),rainfall over the Yangtze River valley associated with SST anomalies in the western tropical Pacific (WTP-YRV),and rainfall over the Ycllow River loop valley associated with tropical Pacific meridional mode-like SST pattern (TPMM-YRLV).These coupled SVD modes appear robust and closely correlated with the single field,Furthermore,the covariabilities among of the three coupled modes have different characteristics at the decadal time scale.In addition,the possible atmospheric teleconnections of the coupled rainfall and SST modes were discussed.For the ENSO-NC mode,anomalous low-pressure and high-pressure over the Asian continent induces moisture divergence over North China and reduces summer rainfall there.For the WTP-YRV mode,East Asia-Pacific teleconnection induces moisture convergence over the Yangtze River valley and enhances the summer rainfall there.The TPMM SST and the summer rainfall anomalies over the YRVL are linked by a circumglobal,wave-train-like,atmospheric teleconnection.

  12. Impacts of earthquake on atoll in Nansha Islands, South China Sea

    Science.gov (United States)

    Guo, Lei; Zhan, Wenhuan; Xiong, Lijia; Chen, Wujin; Yao, Yantao; Li, Jian

    2016-04-01

    Coral reef is a kind of rock soil masses. It is a special marine geotechnical medium, which are made up of the reef coral debris undergo very long geological age. Atoll is the predominant type of coral reefs in South China Sea. In recent years, there are more and more construction projects on the reef flat in Nansha Islands, South China Sea. Therefore, it is very important to estimate the stability of coral reefs, especially the atolls. According to the geological structure characters of atoll in Nansha Islands, a model of reef body is presented in this paper to study the influence of earthquake. Meanwhile, Geostudio, which is a popular geotechnical engineering simulation software, is used to stimulate the stress and deformation situation of reef body under different six kinds of earthquake intensity. The factor of safety can be calculated by the limit equilibrium method. And the possible scenario of earthquake-induced landslides and sliding scale can be defined through the Newmark sliding block method. The stress distribution and deformation behavior are studied. The main relations between atoll and earthquake are analyzed as follows: (1) the safety factor of reef slope exceeds 1.993 under self-gravity state; (2) It may cause slope's instability and bring slumping when the safety factor is less than one. The factor of safety decreases with increased earthquake intensity and it may fluctuate around a particular value when earthquake intensity continues to increase; (3) The smaller shallow landslide as new developed part of the reef is subject to collapse under earthquake action and the bigger slope of reef is more stable. The results show that it is feasible to evaluate the stability of coral reef by using geotechnical engineering simulation method, which can help to provide some information for construction on coral reefs in South China Sea. In the meantime,the authers wish to thank the National Natural Science Foundation of China (NO.41376063)and the National

  13. Observation of Directional Ocean Wave Spectra in China Seas and Northwest Pacific Ocean Using SAR Retrieval Software

    Science.gov (United States)

    Liu, Xiaoyan; Zeng, Kan; He, Mingxia

    2014-11-01

    A software to retrieve directional ocean wave spectra from SAR images has been developed for China seas and northwest Pacific. The software, written with C programming language, is based on the MPI method proposed by Hasselmann. It is designed to support the wave mode SAR data of ERS, Envisat, Sentinel and so on. The directional ocean wave spectra produced by this software are validated with buoy data in global ocean area, northwest Pacific and China seas and the retrieved significant wave height (SWH) errors are 5.2%, 4.9% and 9.3% respectively. About 15,000 directional ocean wave spectra are obtained with the software from the wave mode data of Envisat/ASAR over the China seas and northwest Pacific during the period between Jan 2003 and Jan 2012. The preliminary analysis is presented.

  14. Sporopollen and algae research of core B106 in the northern South China Sea and its paleoenvironmental evolution

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Based on the high-resolution sporopollen and algae research of the sediments from core B106 in the northem South China Sea,three sporopollen assemblage zones have been distinguished in ascending order:Zone 1 (294-194 cm):pinus-Quercus (evergreen)-Gramineae-Polypodia-ceae- Pterdium-Dicranopteris.Zone 2 (194-94 cm):Pinus-Quercus (evergreen)-Polypodiaceae-Pteridium- Dicranopteris.Zone 3 (94-4 cm):Pinus-Polypodiaceae-Pteridium-Quercus(evergreen)-Dicranopteris.The three sporopollen zones correspond to three stages of vegetation,climate and paleoenvironment evolution of the northern part of the South China Sea since 11 000 years ago.Combined with AMS 14C dating,the sporopollen and algae data can be a scientific basis for stratigraphic division and reconstruction of paleoclimate and paleoenvironment in the South China Sea.

  15. Surface elevation change and susceptibility of coastal wetlands to sea level rise in Liaohe Delta, China

    Science.gov (United States)

    Wang, Guo-dong; Wang, Ming; Lu, Xian-guo; Jiang, Ming

    2016-10-01

    The Liaohe Delta in China is an ecologically and commercially important wetland system under threat from sea level rise and marsh subsidence. Sediments deposited in coastal marshes could offer wetlands a potentially important means for adjusting surface elevation with rising sea level, yet coastal wetland stability in Liaohe Delta is not well understood due to limited data from long-term experiments. In this study, wetland surface elevation and vertical accretion were measured from 2011 to 2015 using a surface elevation table (SET) and feldspar marker horizons in two Phragmites and two Suaeda marshes receiving Liaohe River water. The analysis shows that the Phragmites marshes exhibited higher rates of marsh accretion and elevation change than the Suaeda marshes. The two Phragmites marsh sites had average surface elevation change rates at 8.8 and 9.3 mm yr-1, vertical accretion at 17.4 and 17.6 mm yr-1, and shallow subsidence at 8.6 and 8.3 mm yr-1. The average rates of elevation change, vertical accretion, and shallow subsidence at two Suaeda marsh sites were 5.8 and 6.3 mm yr-1, 13.6 and 14.8 mm yr-1, and 7.8 and 8.5 mm yr-1, respectively. The trends suggest that coastal marshes in Liaohe Delta are experiencing changes in average soil elevation that range from a net increase of 0.3 mm y-1 to 6.9 mm y-1 relative to averaged sea level rise in Bohai Sea reported by the 2016 State Oceanic Administration People's Republic of China projection (2.4-5.5 mm y-1), which indicated that the four wetland sites would adjust to the sea level rise and even continue to gain elevation, especially for the Phragmites sites. Nevertheless, the vulnerability of coastal wetlands in Liaohe Delta need further assessment considering the accelerated sea level rise, the high rate of subsidence, and the declining sediment delivery owing to anthropogenic activities such as dam constructions in the river basin.

  16. Double SST fronts observed from MODIS data in the East China Sea off the Zhejiang-Fujian coast, China

    Science.gov (United States)

    He, Shuangyan; Huang, Daji; Zeng, Dingyong

    2016-02-01

    We report a double coastal front system off the Zhejiang (Zhe) and Fujian (Min) Provinces in the East China Sea in winter. In addition to the well-known Zhe-Min offshore coastal front along 50 m isobath, a secondary near-shore coastal thermal front along 20 m isobath is also apparent in December and January. The fronts were observed by Moderate Resolution Imaging Spectroradiometer (MODIS) at monthly mean nighttime sea surface temperature (SST) during 2000-2013 in terms of SST gradients. Our results showed temporal and spatial variations of the two fronts as follows: (1) both offshore front and near-shore front often co-exist between 26.5°N and 29.5°N in December and between 28.0°N and 29.5°N in January. However, only the offshore front is apparent in November and February. (2) The near-shore front is narrow (4-16 km), while the offshore front is three to four times wider (16-48 km). (3) In contrast to the well-known offshore front which exists throughout the winter with a strong intensity, the near-shore front has a shorter lifetime with a weak intensity, and has been overlooked by previous studies. Finally, we proposed that the bottom bathymetric gradients may play an important role in the frontogenesis of the double fronts.

  17. Validation and Variation of Upper Layer Thickness in South China Sea from Satellite Altimeter Data

    Directory of Open Access Journals (Sweden)

    Nan-Jung Kuo

    2008-06-01

    Full Text Available Satellite altimeter data from 1993 to 2005 has been used to analyze the seasonal variation and the interannual variability of upper layer thickness (ULT in the South China Sea (SCS. Base on in-situ measurements, the ULT is defined as the thickness from the sea surface to the depth of 16°C isotherm which is used to validate the result derived from satellite altimeter data. In comparison with altimeter and in-situ derived ULTs yields a correlation coefficient of 0.92 with a slope of 0.95 and an intercept of 6 m. The basin averaged ULT derived from altimeter is 160 m in winter and 171 m in summer which is similar to the in-situ measurements of 159 m in winter and 175 m in summer. Both results also show similar spatial patterns. It suggests that the sea surface height data derived from satellite sensors are usable for study the variation of ULT in the semi-closed SCS. Furthermore, we also use satellite derived ULT to detect the development of eddy. Interannual variability of two meso-scale cyclonic eddies and one anticyclonic eddy are strongly influenced by El Niño events. In most cases, there are highly positive correlations between ULT and sea surface temperature except the periods of El Niño. During the onset of El Niño event, ULT is deeper when sea surface temperature is lower.

  18. Impacts of South East Biomass Burning on local air quality in South China Sea

    Science.gov (United States)

    Wai-man Yeung, Irene; Fat Lam, Yun; Eniolu Morakinyo, Tobi

    2016-04-01

    Biomass burning is a significant source of carbon monoxide and particulate matter, which is not only contribute to the local air pollution, but also regional air pollution. This study investigated the impacts of biomass burning emissions from Southeast Asia (SEA) as well as its contribution to the local air pollution in East and South China Sea, including Hong Kong and Taiwan. Three years (2012 - 2014) of the Hybrid Single Particle Lagrangian-Integrated Trajectory (HYSPLIT) with particles dispersion analyses using NCEP (Final) Operational Global Analysis data (FNL) data (2012 - 2014) were analyzed to track down all possible long-range transport from SEA with a sinking motion that worsened the surface air quality (tropospheric downwash from the free troposphere). The major sources of SEA biomass burning emissions were first identified using high fire emissions from the Global Fire Emission Database (GFED), followed by the HYSPLIT backward trajectory dispersion modeling analysis. The analyses were compared with the local observation data from Tai Mo Shan (1,000 msl) and Tap Mun (60 msl) in Hong Kong, as well as the data from Lulin mountain (2,600 msl) in Taiwan, to assess the possible impacts of SEA biomass burning on local air quality. The correlation between long-range transport events from the particles dispersion results and locally observed air quality data indicated that the background concentrations of ozone, PM2.5 and PM10 at the surface stations were enhanced by 12 μg/m3, 4 μg/m3 and 7 μg/m3, respectively, while the long-range transport contributed to enhancements of 4 μg/m3, 4 μg/m3 and 8 μg/m3 for O3, PM2.5 and PM10, respectively at the lower free atmosphere.

  19. Remote sensing model and dynamic mechanism for seasonal changes of the euphotic depth in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    LI Guosheng; YANG Shilin; LIANG Qiang

    2003-01-01

    Based on remote sensing data and models, spatial distribution of the monthly euphotic depth in the East China Sea in 1998 has been obtained. The character of the seasonal changes of the euphotic depth is summarized, and the dynamic mechanism of the key influencing factors is analyzed. The results indicate that the controlling factors of the seasonal changes of euphotic depth in the East China Sea are the seasonal changes of temperature, diluted water from the Yangtze River, the ocean currents and the front process of different water masses.

  20. Errors of Mean Dynamic Topography and Geostrophic Current Estimates in China's Marginal Seas from GOCE and Satellite Altimetry

    DEFF Research Database (Denmark)

    Jin, Shuanggen; Feng, Guiping; Andersen, Ole Baltazar

    2014-01-01

    The Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) and satellite altimetry can provide very detailed and accurate estimates of the mean dynamic topography (MDT) and geostrophic currents in China's marginal seas, such as, the newest high-resolution GOCE gravity field model GO...... and geostrophic current estimates from satellite gravimetry and altimetry are investigated and evaluated in China's marginal seas. The cumulative error in MDT from GOCE is reduced from 22.75 to 9.89 cm when compared to the Gravity Recovery and Climate Experiment (GRACE) gravity field model ITG...

  1. A Preliminary Study on the Diversity of Fish Species and Marine Fish Faunas of the South China Sea

    Institute of Scientific and Technical Information of China (English)

    MA Caihua; YOU Kui; ZHANG Meizhao; LI Fengqi; CHEN Dagang

    2008-01-01

    There are 3048 species offish occurring in the China Seas (CS), of which at least 2321 species are found in the South China Sea (SCS), belonging to 35 orders, 236 families and 822 genera. The fish species diversity is analyzed in this paper based on biogeography, biostatisties, fishing methods, etc. It is found that the regional environment, especially biological factors, plays an important role in the distribution of faunas, and there are two fish faunas in the SCS, one in the north and another in the center and south. This regional division is of value for sustainable fishery production and efficient management of fishery resources.

  2. Effects of the Thermal Contrast Between Indo-China Peninsula and South China Sea on the SCS Monsoon Onset

    Institute of Scientific and Technical Information of China (English)

    LIU Xuanfei; LI Qing; HE Jinhai; WANG Ping

    2010-01-01

    The seasonal and interannual variations of the thermal contrast between Indo-China Peninsula (ICP) and South China Sea (SCS) were analyzed using the pentad mean NCEP/NCAR reanalysis data during 1958-1998 and the pentad mean outgoing long-wave radiation (OLR) data during 1975-1998, along with the effects of such a thermal contrast on the SCS monsoon onset (SCSMO). It is shown that there exists significant seasonal evolution for such a thermal contrast. The surface temperature of ICP is higher than that of SCS from pentad 3 to pentad 25 due to the sensible heating of the ICP. After pentad 25, such a thermal gradient reverses due to the temperature decrease resulted from the convection and rainfall over the ICP from pentad 22 to pentad 23. Furthermore, the above seasonal evolution of the discussed thermal contrast also demonstrates a remarkable interannual change which plays an important role in the SCSMO. On one hand, the reversion happens prior to (or simultaneously with) the SCSMO each year during 1958-1998, thus becoming a precondition for the SCSMO. On the other hand, the earlier (later) the date when the surface temperature of ICP becomes higher (lower) than that of the SCS, the later the SCSMO.

  3. Air–sea CO2 fluxes in the East China Sea based on multiple-year underway observations

    Directory of Open Access Journals (Sweden)

    X.-H. Guo

    2015-04-01

    Full Text Available This study reports thus far a most comprehensive dataset of surface seawater pCO2 (partial pressure of CO2 and the associated air–sea CO2 fluxes in a major ocean margin, the East China Sea (ECS based on 24 surveys conducted in 2006 to 2011. We showed highly dynamic spatial variability of sea surface pCO2 in the ECS except in winter when it ranged in a narrow band of 330 to 360 μatm. In this context, we categorized the ECS into five different domains featured with different physics and biogeochemistry to better characterize the seasonality of the pCO2 dynamics and to better constrain the CO2 flux. The five domains are (I the outer Changjiang estuary and Changjiang plume, (II the Zhejiang–Fujian coast, (III the northern ECS shelf, (IV the middle ECS shelf, and (V the southern ECS shelf. In spring and summer, pCO2 off the Changjiang estuary was as low as 400 μatm in fall. pCO2 along the Zhejiang–Fujian coast was low in spring, summer and winter (300 to 350 μatm but was relatively high in fall (> 350 μatm. In the northern ECS shelf, pCO2 in summer and fall was > 340 μatm in most areas, higher than in winter and spring. In the middle and southern ECS shelf, pCO2 in summer ranged from 380 to 400 μatm, which was higher than in other seasons (2 flux in the entire ECS shelf was −10.0 ± 2.0 mmol m−2 d−1 in winter, −11.7 ± 3.6 mmol m−2 d−1 in spring, −3.5 ± 4.6 mmol m−2 d−1 in summer and −2.3 ± 3.1 mmol m−2 d−1 in fall. It is important to note that the standard deviations in these flux ranges mostly reflect the spatial variation of pCO2, which differ from the spatial variance nor the bulk uncertainty. Nevertheless, on an annual basis, the average CO2 influx into the entire ECS shelf was −6.9 ± 4.0 mmol m−2 d−1, about twice the global average in ocean margins.

  4. Spatio-temporal variations in the siphonophore community of the northern South China Sea

    Institute of Scientific and Technical Information of China (English)

    LI Kaizhi; YIN Jianqiang; HUANG Liangmin; LIAN Shumin; ZHANG Jianlin

    2013-01-01

    To understand how hydrological and biological factors affect near-to off-shore variations in the siphonophore community,we sampled zooplankton at 82 stations in the northern South China Sea during summer,winter,and spring.Forty-one species of siphonophore were collected by vertical trawling.The species richness of siphonophores increased from the nearshore to offshore regions in all three seasons of investigation,with maximum richness in summer and minimum richness in winter.The abundance of siphonophores was also higher in summer than in spring and winter,concentrated in the nearshore region in the warm season and scattered in the offshore region in the cold season.Four siphonophore groups were classified according to the frequency of occurrence:nearshore,near-offshore,offshore,and tropical pelagic.Among them,the nearshore group had higher abundance nearshore compared with the offshore.The tropical pelagic group had higher species number offshore than nearshore.Spatial and temporal fluctuations in taxonomic composition and abundance of siphonophores were due to the influence of the coastal upwelling and surface ocean currents of the South China Sea,driven by the East Asia monsoonal system.

  5. Diagnostic analysis on the northern South China Sea winter counter-wind current

    Institute of Scientific and Technical Information of China (English)

    HONG Bo; WANG Dongxiao

    2006-01-01

    The winter counter-wind current (also named the South China Sea Warm Current (SCSWC)) in the northern South China Sea (SCS)has been known well for decades, but its mass and momentum origination have not be quantitatively evaluated before. In this paper, the high resolution three-dimensional ocean circulation model is adopted to reproduce the circulation in the northern SCS. The diagnostic analyses are performed to investigate the momentum budget in the northern SCS continental shelf/slope and the momentum propulsion of the SCSWC. It is indicated that the across-shelf pressure gradient and the across-shelf transport are responsible for the formation of the SCSWC, while the along-shelf pressure gradient is balanced by the surface stress, bottom stress, and Coriolis force. The magnitude of the terms in the along-shelf momentum equation is smaller than that in the across-shelf one.The analysis on the momentum budget in the northern SCS will benefit the marine environmental prediction in the future.

  6. Simulating a typhoon storm surge in the East Sea of China using a coupled model

    Institute of Scientific and Technical Information of China (English)

    Baoshu Yin; Zhenhua Xu; Yong Huang; Xiang Lin

    2009-01-01

    A coupled numerical model with a 2'× 2' resolution grid has been developed and used to simulate five typical typhoon storm surges (5612,7413,7910,8114,and 9711) in the East Sea of China.Three main driving forces have been considered in this coupled model:wave radiation stress,combined wave-current bottom shear stress and wave-state-dependent surface wind stress.This model has then been compared with in situ measurements of the storm set-up.The effect of different driving force components on the total storm surge has also been investigated.This study has found that the coupled model with high resolution is capable of simulating the five typical typhoons better than the uncoupled models,and that the wave-dependent surface wind stress plays an important role in typhoon storm surge-wave coupling in this area and can increase the storm set-up by 1 m.The study of the five typhoon cases has shown that the general coupling effects could increase storm set-up by 20-32%.Thus,it is suggested that to predict typhoon storm surges in the East Sea of China,a storm surge-wave coupled model be adopted.

  7. Analysis and Design of Trial Well Mooring in Deepwater of the South China Sea

    Institute of Scientific and Technical Information of China (English)

    Yongfeng Guo; Shaojun Ji; Changquan Tang; Jiansong Li; Huiquan Zhong; Ong Chin Yam Ian

    2012-01-01

    Mooring systems play an important role for semi-submersible rigs that drill in deepwater.A detailed analysis was carried out on the mooring of a semi-submersible rig that conducted a trial well drilling at a deepwater location in the South China Sea in 2009.The rig was 30 years old and had a shallow platform with a designed maximum operating water depth of 457 m.Following the mooring analysis,a mooring design was given that requires upgrading of the rig's original mooring system.The upgrade included several innovations,such as installing eight larger anchors,i.e.replacing the original anchors and inserting an additional 600 m of steel wires with the existing chains.All this was done to enhance the mooring capability of the rig in order for the rig to be held in position to conduct drilling at a water depth of 476 m.The overall duration of the drilling was 50 days and the upgraded mooring system proved to be efficient in achieving the goal of keeping the rig stationary while it was drilling the trial well in the South China Sea.This successful campaign demonstrates that an older semi-submersible rig can take on drilling in deep water after careful design and proper upgrading and modification to the original mooring system.

  8. Geomagnetic paleointensity dating of South China Sea sediments for the last 130 kyr

    Science.gov (United States)

    Xiaoqiang, Yang; Heller, Friedrich; Nengyou, Wu; Jie, Yang; Zhihua, Su

    2009-06-01

    Relative paleointensity records from the northern South China Sea, northwest Pacific Ocean were studied in two gravity piston cores. Continuous mineral magnetic and paleomagnetic measurements were made using discrete sediment samples. Detailed rock magnetic parameters, such as thermomagnetic and high-field hysteresis data, indicate that pseudo-single domain magnetite in a narrow range of grain-size and concentration is the main contributor to the remanent magnetization. The uniform magnetic mineralogy meets the commonly accepted criteria for establishing relative paleointensity records. The relative paleointensity (RPI) curves were constructed by normalizing the natural remanent magnetization (NRM) with isothermal remanent magnetization (IRM), both in the 20-60 mT demagnetization state. Dating constraints have been provided by radiocarbon ages in the upper 400 cm of both cores. Furthermore, we have correlated our paleointensity records with NAPIS-75, S.Atlantic-1089, Sint-200 and NOPAPIS-250 to determine the chronological RPI framework for the South China Sea (SCS-PIS). Although some temporal offsets of paleointensity features between the different records have been recognized, their similar shape suggests that relative paleointensity on the 10 3-10 4 year scale is globally coherent and can provide an age framework for sediments independent of δ18O ages.

  9. Benthic foraminiferal fauna turnover at 2.1 Ma in the northern South China Sea

    Institute of Scientific and Technical Information of China (English)

    HUANG BaoQi; JIAN ZhiMin; WANG PinXian

    2007-01-01

    Quantitative analysis of benthic foraminifera from ODP Site 1146 in the northern South China Sea (SCS)shows that abundance of Bulimina alazanensis, sometimes up to about 90%, decreased gradually since 3.2 Ma, especially at 2.1 Ma. Abundance of other benthic foraminiferal species, Globobulimina subglobosa and Cibicidoides wuellerstorfi, increased after 2.1 Ma. Comparison with changes in oxygen and carbon isotopes of planktonic and benthic foraminifera shows that high abundance values of B.alazanensis corresponded with lower values of oxygen isotope, but for carbon isotope, high values of the species were consistent with heavier carbon Isotope of benthic foraminifera and lighter carbon isotope of planktonic foraminifera, respectively, and vice versa. Considering factors such as uplift of Bashi Strait, expansion of the North Hemisphere Glaciation, strengthening of East Asian winter monsoon and variations in oxygen and carbon isotope of foraminifera, changes of B. alazanensis in ODP Site 1146 suggest that the source of deep water masses of the northern South China Sea changed from the warm Pacific deep water with high oxygen content to Pacific Intermediate water with Iow oxygen content at 2.1 Ma. In addition, the strengthened East Asian winter monsoon resulted in increased primary productivity, high nutrient and suboxic bottom water. Variations in species of B. alazanensis seemed to be unable to tolerate environmental stress induced by deep water masses and productivity changes.

  10. Propagated rifting in the Southwest Sub-basin, South China Sea: Insights from analogue modelling

    Science.gov (United States)

    Ding, Weiwei; Li, Jiabiao

    2016-10-01

    How the South China Sea rifted has long been a puzzling question that is still debated, particularly with reference to the Southwest Sub-basin (SWSB). Analogue modelling remains one of the most useful tools for testing rift models and processes. Here, we present and discuss a series of analogue modelling experiments designed to investigate the rifting process of the SWSB. Convincing geophysical results were compiled to provide realistic constraints to test the experimental results and interpretations. A heterogeneous lithosphere model with a varied lithospheric structure showed tectono-morphological features similar to the natural case of the SWSB, indicating that the initial thermal condition and rheological stratification of the lithosphere should have a dominant effect on the rifting process of the SWSB. Rigid tectonic blocks existed in the continental margin, such as the Macclesfield Bank and the Reed Bank, and they played important roles in both the shaping of the continent-ocean boundary and the coupling between the crust and mantle. The initial thermal condition and rheological stratification of the lithosphere under the South China Sea controlled the propagated rifting process of the SWSB. Extension was centred on the deep troughs between the rigid blocks, and the break-up occurred in these areas between them. The westward rifting propagation is best explained with a heterogeneous lithosphere model characterized by varied lithospheric structure, and it was responsible for producing the V-shaped configuration of the SWSB.

  11. Observed 3D Structure, Generation, and Dissipation of Oceanic Mesoscale Eddies in the South China Sea

    Science.gov (United States)

    Zhang, Zhiwei; Tian, Jiwei; Qiu, Bo; Zhao, Wei; Chang, Ping; Wu, Dexing; Wan, Xiuquan

    2016-04-01

    Oceanic mesoscale eddies with horizontal scales of 50–300 km are the most energetic form of flows in the ocean. They are the oceanic analogues of atmospheric storms and are effective transporters of heat, nutrients, dissolved carbon, and other biochemical materials in the ocean. Although oceanic eddies have been ubiquitously observed in the world oceans since 1960s, our understanding of their three-dimensional (3D) structure, generation, and dissipation remains fragmentary due to lack of systematic full water-depth measurements. To bridge this knowledge gap, we designed and conducted a multi-months field campaign, called the South China Sea Mesoscale Eddy Experiment (S-MEE), in the northern South China Sea in 2013/2014. The S-MEE for the first time captured full-depth 3D structures of an anticyclonic and cyclonic eddy pair, which are characterized by a distinct vertical tilt of their axes. By observing the eddy evolution at an upstream versus downstream location and conducting an eddy energy budget analysis, the authors further proposed that generation of submesoscale motions most likely constitutes the dominant dissipation mechanism for the observed eddies.

  12. Response of internal solitary waves to tropical storm Washi in the northwestern South China Sea

    Directory of Open Access Journals (Sweden)

    Z. H. Xu

    2011-11-01

    Full Text Available Based on in-situ time series data from an array of temperature sensors and an acoustic Doppler current profiler on the continental shelf of the northwestern South China Sea, a sequence of internal solitary waves (ISWs were observed during the passage of tropical storm Washi in the summer of 2005, which provided a unique opportunity to investigate the ISW response to the tropical cyclone. The passing tropical storm is found to play an important role in affecting the stratification structure of the water column, and consequently leading to significant variability in the propagating features of the ISWs, such as the polarity reversal and amplitude variations of the waves. The response of the ISWs to Washi can be divided into two stages, direct forcing by the strong wind (during the arrival of Washi and remote forcing via the near-inertial internal waves induced by the tropical storm (after the passage of Washi. The field observations as well as a theoretical analysis suggest that the variations of the ISWs closely coincide with the changing stratification structure and shear currents in accompanied by the typhoon wind and near-inertial waves. This study presents the first observations and analysis of the ISW response to the tropical cyclone in the South China Sea.

  13. Benthic fluxes of dissolved organic carbon from gas hydrate sediments in the northern South China Sea

    Science.gov (United States)

    Hung, Chia-Wei; Huang, Kuo-Hao; Shih, Yung-Yen; Lin, Yu-Shih; Chen, Hsin-Hung; Wang, Chau-Chang; Ho, Chuang-Yi; Hung, Chin-Chang; Burdige, David J.

    2016-07-01

    Hydrocarbon vents have recently been reported to contribute considerable amounts of dissolved organic carbon (DOC) to the oceans. Many such hydrocarbon vents widely exist in the northern South China Sea (NSCS). To investigate if these hydrocarbon vent sites release DOC, we used a real-time video multiple-corer to collect bottom seawater and surface sediments at vent sites. We analyzed concentrations of DOC in these samples and estimated DOC fluxes. Elevated DOC concentrations in the porewaters were found at some sites suggesting that DOC may come from these hydrocarbon vents. Benthic fluxes of DOC from these sediments were 28 to 1264 μmol m‑2 d‑1 (on average ~321 μmol m‑2 d‑1) which are several times higher than most DOC fluxes in coastal and continental margin sediments. The results demonstrate that the real-time video multiple-corer can precisely collect samples at vent sites. The estimated benthic DOC flux from the methane venting sites (8.6 × 106 mol y‑1), is 24% of the DOC discharge from the Pearl River to the South China Sea, indicating that these sediments make an important contribution to the DOC in deep waters.

  14. Development of typhoon driven wave nowcasting model in Southeast China Sea

    Institute of Scientific and Technical Information of China (English)

    Zheng Jinhai; Feng Xiangbo; Yan Yixin

    2011-01-01

    Using optimal interpolation data assimilation of observed wave spectrum around Northeast coast of Taiwan Island, the typhoon driven wave nowcasting model in Southeast China Sea is setup. The SWAN ( simulating waves nearshore) model is used to calculate wave field and the input wind field is the QSCAT/NCEP (Quick Scatterometer/National Centers for Environmental Prediction) data. The two-dimensional wavelet transform is applied to analyze the Xband radar image of nearshore wave field and it reveals that the observed wave spectrum has shoaling characteristics in frequency domain. The reverse calculation approach of wave spectrum in deep water is proposed and validated with experimental tests. The two-dimensional digital low-pass filter is used to obtain the initialization wave field. Wave data during Typhoon Sinlaku is used to calibrate the data assimilation parameters and test the reverse calculation approach. Data assimilation corrects the significant wave height and the low frequency spectra energy evidently at Beishuang Station along Fujian Province coast, where the entire assimilation indexes are positive in verification moments. The nowcasting wave field shows that the present model can obtain more accurate wave predictions for coastal and ocean engineering in Southeast China Sea.

  15. Vertical distribution and indications of lipids biomarkers in the sediment core from East China Sea

    Science.gov (United States)

    Wang, Rui; Wang, Jiangtao; Li, Feng; Yang, Shu; Tan, Liju

    2016-07-01

    To study the distribution and indications of lipids biomarkers in the mud areas of the East China Sea shelf, a sediment core was collected. Lipids were determined to find the origination of different organic matter (fatty acids and sterols) inputs. The results demonstrated that the distribution of fatty acids and sterols indicated the organic matter derived from the mixed allochthonous and autochthonous sources, but mainly autochthonous. The total fatty acids concentrations ranged from 29.08 μg g-1 to 303.92 μg g-1 and exhibited unimodal distribution with the predominance of C16-fatty acid. Neutral lipid concentrations ranged from 1.77 μg g-1 to 4.65 μg g-1. Furthermore, the distribution patterns of sterols varied with depth, and were dominated by C27-sterol and C29-sterol in the top and bottom sediments respectively. Although bacterial lipids were recruited during diagenesis, the refractory terrestrial lipids were usually preferentially preserved. This records dated from the 1980s suggested that the phytoplankton community was mainly influenced by eutrophication in the East China Sea and this variation may be recorded by lipid biomarkers deposited in the sediment.

  16. Modern microbialites and their environmental significance, Meiji reef atoll, Nansha (Spratly) Islands, South China Sea

    Institute of Scientific and Technical Information of China (English)

    SHEN JianWei; WANG Yue

    2008-01-01

    Meiji (Mischief) coral atoll, in Nansha (Spratly) Islands, South China Sea, consists of an annular reef rim surrounding a central lagoon. On the atoll rim there are either protuberant 'motu' (small coral patch reefs on the rim of atoll) islets or lower sandy cays that contain modern microbialite deposits on the corals in pinnacles and surrounding bottoms of the atoll. Microbialites, including villiform, hairy, and thin spine growth forms, as well as gelatinous masses, mats and encruststion, developed on coral colonies and atoll rim sediments between 0 and 15 m deep-water settings. The microbialites were produced by natural populations of filamentous cyanobacteria and grew on (1) bulbous corals together with Acropora sp., (2) on massive colonies of Galaxea fascicularis, (3) on dead Montipora digitata, and (4) on dead Acropora teres, some hairy microbialite growing around broken coral branches. This study demonstrates that microbial carbonates are developed in coral reefs of South China Sea and indicates that microbial processes may be important in the construction of modern reef systems. The results have significance in the determination of nature and composition in microorganisms implied in the formation ancient microbialites, and permit evaluation of the importance of microbial deposits in modern coral reefs and of 'microbialites' in biogeochemical cycles of modern coral reef systems. The results also provide evidence of modern analogues for ancient microbialites in shallow-water settings, and combine with sedimentological studies of ancient microbialites to understand their controls.

  17. The Functions of China Marginal Sea Sediments in the Cycle of Biogenic Elements

    Institute of Scientific and Technical Information of China (English)

    Sun Yunming; Song Jinming

    2002-01-01

    The contents of biogenic elements in China marginal sea sediments are related to their grain sizes, river transport, et al. In general, the finer the grain size is, the higher the contents of organic matter and OC, N, P are, the lower the contents of S and Si are. The biogeochemical environments of sediments are related to Eh, pH, temperature content of OC,Fe3+/Fe2+ radio, water dynamics condition, grain size of sediment, S system in sediment interstitial waters, et al., and they influence the early diageneses and cycle of biogenic elements in sediments. In most regions of China marginal sea, the flux directions of S2-, HS-,3- NH4+H4SiO4, PO4 , across the sediment-water interface are from sediment to the overlying seawater, the flux directions of SO42-, HCO3-, NO3-, NO2- across the sediment-water interface are from the overlying seawater to sediment. The irrigation of living things is important in the cycle of the biogenic elements across sediment-water interfaces.

  18. Assessment for water quality by artificial neural network in Daya Bay, South China Sea.

    Science.gov (United States)

    Wu, Mei-Lin; Wang, You-Shao; Gu, Ji-Dong

    2015-10-01

    In this study, artificial neural network such as a self-organizing map (SOM) was used to assess for the effects caused by climate change and human activities on the water quality in Daya Bay, South China Sea. SOM has identified the anthropogenic effects and seasonal characters of water quality. SOM grouped the four seasons as four groups (winter, spring, summer and autumn). The Southeast Asian monsoons, northeasterly from October to the next April and southwesterly from May to September have also an important influence on the water quality in Daya Bay. Spatial pattern is mainly related to anthropogenic activities and hydrodynamics conditions. In spatial characteristics, the water quality in Daya Bay was divided into two groups by chemometrics. The monitoring stations (S3, S8, S10 and S11) were in these area (Dapeng Ao, Aotou Harbor) and northeast parts of Daya Bay, which are areas of human activity. The thermal pollution has been observed near water body in Daya Bay Nuclear Power Plant (S5). The rest of the monitoring sites were in the south, central and eastern parts of Daya Bay, which are areas that experience water exchanges from South China Sea. The results of this study may provide information on the spatial and temporal patterns in Daya Bay. Further research will be carry out more research concerning functional changes in the bay ecology with respect to changes in climatic factor, human activities and bay morphology in Daya Bay. PMID:25847104

  19. Benthic fluxes of dissolved organic carbon from gas hydrate sediments in the northern South China Sea.

    Science.gov (United States)

    Hung, Chia-Wei; Huang, Kuo-Hao; Shih, Yung-Yen; Lin, Yu-Shih; Chen, Hsin-Hung; Wang, Chau-Chang; Ho, Chuang-Yi; Hung, Chin-Chang; Burdige, David J

    2016-01-01

    Hydrocarbon vents have recently been reported to contribute considerable amounts of dissolved organic carbon (DOC) to the oceans. Many such hydrocarbon vents widely exist in the northern South China Sea (NSCS). To investigate if these hydrocarbon vent sites release DOC, we used a real-time video multiple-corer to collect bottom seawater and surface sediments at vent sites. We analyzed concentrations of DOC in these samples and estimated DOC fluxes. Elevated DOC concentrations in the porewaters were found at some sites suggesting that DOC may come from these hydrocarbon vents. Benthic fluxes of DOC from these sediments were 28 to 1264 μmol m(-2 )d(-1) (on average ~321 μmol m(-2 )d(-1)) which are several times higher than most DOC fluxes in coastal and continental margin sediments. The results demonstrate that the real-time video multiple-corer can precisely collect samples at vent sites. The estimated benthic DOC flux from the methane venting sites (8.6 × 10(6 )mol y(-1)), is 24% of the DOC discharge from the Pearl River to the South China Sea, indicating that these sediments make an important contribution to the DOC in deep waters. PMID:27432631

  20. REEXAMINATION OF THE ROLE OF VERTICAL CIRCULATION IN SEDIMENTATION IN THE YELLOW AND EAST CHINA SEAS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Based on figures available, role of upwelling in some fine sediment patches on China Sea shelves is examined from the viewpoints of physical process and biological process, respectively. It is further vertified with more data wherever upwelling exists on continental shelf mud must occur-coincidence of upwelling areas with mud patches. Marine rain is named for physical process and marine snow is used as usual. It is pointed out that marine rain and marine snow are usually coexistent and interact each other. It is concluded that the mud patch southeast of Cheju Is. is formed by marine rain rather than marine snow since terrigenous elements are high and biogenic elements are not and that judging from sediment trap data the mud in the Okinawa Trough is accumulated by horizontal transport via wind-driven transverse circulation from inner shelf in winter and by vertical flux through biological activities (marine snow) and aeolian deposit in spring.   A number of controversies on fine sediment issues on China Sea shelves need to be further deliberated. Interaction between marine rain and snow also needs to be experimentally and theoretically studied.

  1. 解读奥巴马政府的南海政策%Interpreting Obama Administration's South China Sea Policy

    Institute of Scientific and Technical Information of China (English)

    韦宗友

    2016-01-01

    自2010年以来,奥巴马政府的南海政策日益朝着“积极干涉”和“选边站”的立场转移,给中美关系及南海问题的解决增添了新变数。奥巴马政府不仅对中国的“断续线”主张提出质疑,还指责中国阻碍南海航行自由,要求中国停止在南海填海造地,鼓动菲律宾将南海争端提交国际仲裁,推动南海问题的国际化与多边化,积极向越南、菲律宾等国提供外交帮助和军事支持,甚至直接派遣飞机和舰船进入南海争议地区。奥巴马政府在南海问题上日益积极的干涉立场与举措,不仅折射出美国对中国战略意图和海洋抱负与日俱增的忧虑,也反映出美国维护亚太领导权、安抚亚太盟友及维护其海洋霸权的战略决心与考量。在美国国内对华强硬的声音抬头、中美在亚太地区竞争加剧及美国政治正进入大选周期的背景下,美国在南海问题上“积极干涉”和“选边站”的态势只会加强而不会弱化,并可能采取一些新的措施。中国需要综合平衡各种利害关系,积极稳妥应对南海困局。%Since 2010, the Obama administration's South China Sea policy has moved steadily toward posi-tive intervention and side-choosing, which negatively impacted Sino-U.S.relations and complicated the South China Sea issues.The Obama administration not only doubted the legality of China's nine-dash line claims, but also charged that China has interfered with the freedom of navigation in the South China Sea, and urged China to stop land reclamation in the South China Sea.Besides, U.S.also encouraged the Philippines'efforts to submit its maritime disputes with China to international arbitration to internationalize and multilateralize the South China Sea disputes, provided diplomatic support and military aid to Vietnam, the Philippines and other claimants, and even sent airplanes and ships to the disputed area.The change of Obama

  2. Molecular biomarker record of paleooceanographic envi-ronment in the East China Sea during the last 35000 years

    Institute of Scientific and Technical Information of China (English)

    MENG; Xianwei

    2002-01-01

    [1]Wang Pinxian, Response of western Pacific marginal seas to glacial cycles: Paleooceanographic and sedimentological features, Marine Geology, 1999, 156: 5-39.[2]Cang Shuxi, Yan Jun, Paleooceanography of Restricted Sea Area, Western Pacific Ocean (in Chinese), Qingdao: Ocean University Press, 1992, 11-32.[3]Xu Xuedong, Motoyosh, O., surface-water evolution of the eastern East China Sea during the last 36000 years, Marine Geology, 1999, 156: 285-304.[4]Yan Jun, Cang Shuxi, Evolution of the paleo-Kuroshio system and its relation to climate change since the last interglacial, Marine Geology & Quaternary Geology (in Chinese), 1995, 15: 26-40.[5]Li Peiying, Wang Yongji, Liu Zhenxia et al., Chronostratigraphy and deposition rates in the Okinawa Trough region, Science in China, Ser. D, 1999, 42(4): 408-413.[6]Liu Zhenxia, Li Tiegang, Li Peiying et al., The Paleoclimatic events and cause in the Okinawa Trough during 50ka BP, Chinese Science Bulletin, 2001, 46(2): 153-157.[7]Tang Yunqian, Zhen Shilong, Liu Kewen, Biomarker distribution in sedimentary core, South China Sea, in Sedimentation Process and Geochemical Study (in Chinese), Beijing: Ocean Press, 1993, 135-141.[8]Dong Guangrong, Wang Guiyong, Li Xiaoze et al., Paleo-monsoon evolution of sandy region in the eastern China during last interglacial, Science in China (in Chinese), Ser. D, 1996, 26(5): 437-444.[9]Pelejero, C., Grimalt, J. O., Sarnthein, M. et al., Molecular biomarker record of sea surface temperature and climatic change in the South China Sea during the last 140000 years, Marine Geology, 1999, 156: 109-121.[10]Prahl, F. G., Pinto, L. A., A geochemical study of long-chain n-alkenones in Washington coastal sediments, Geochim. Cosmochim. Acta, 1987, 51: 1573-1582.[11]Prahl, F. G., Wakeham, S. G., Calibration of unsaturation patterns in long-chain ketone compositions for palaeo-temperature assessment, Nature, 1987, 300: 367-369.[12]Prahl, F. G., Muelhausen, L

  3. Preliminary results of the Source China Sea passive source OBS array experiment

    Science.gov (United States)

    Yang, T.; Liu, C.; Pei, Y.; Xia, S.

    2013-12-01

    The Scarborough, or Huangyan, Seamount chain in South China Sea (SCS) represents an extreme case of the global mid-ocean ridge system where the magmatism continues for many million years after the cessation of spreading. To understand this unique process, the South China Sea Deep (SCSD) program funded an experiment deploying a passive source OBS array to image the lithospheric structure beneath the extinct ridge. In April 2012, 18 passive source OBSs, including 15 Guralp CMG-40T OBS and 3 I-4C OBS, were deployed around the Huangyan Island for one year. 11 OBSs were successfully recovered this April, and their data are being processed. Here we present some preliminary results from analyses of this dataset, including the general quality of three-component seismograms, characteristics of seafloor ambient noise spectra, determining the OBS orientation from the Rayleigh wave polarization, and the dispersion analysis of Rayleigh waves. We found that, for most stations, seismograms from teleseismic, regional and local events are generally good with the horizontal records being comparable with vertical component. The noise levels in these seafloor stations are much higher than land-based stations, especially in shorter periods, likely suggesting the direct and stronger impact from the tempestuous SCS. Applications of more sophisticated seismic techniques such as surface wave tomography, seismic anisotropy, receiver function and ambient noise cross-correlation are underway. In addition to the low recovery rate, there are other lessons learned from this experiment. For example, at least two stations have detectable timing problems; Airgun shots should have been used to constrain the timings and orientations in both deployment and recovery. It is still challenging and costly to carry out long-term passive source seismic observations in deep sea.

  4. Tides and Their Dynamics over the Sunda Shelf of the Southern South China Sea

    Science.gov (United States)

    Ooi, See Hai; Abu Samah, Azizan; Akbari, Abolghasem

    2016-01-01

    A three-dimensional Regional Ocean Modelling System is used to study the tidal characteristics and their dynamics in the Sunda Shelf of the southern South China Sea. In this model, the outer domain is set with a 25 km resolution and the inner one, with a 9 km resolution. Calculations are performed on the inner domain. The model is forced at the sea surface by climatological monthly mean wind stress, freshwater (evaporation minus precipitation), and heat fluxes. Momentum and tracers (such as temperature and salinity) are prescribed in addition to the tidal heights and currents extracted from the Oregon State University TOPEX/Poseidon Global Inverse Solution (TPXO7.2) at the open boundaries. The results are validated against observed tidal amplitudes and phases at 19 locations. Results show that the mean average power energy spectrum (in unit m2/s/cph) for diurnal tides at the southern end of the East Coast of Peninsular Malaysia is approximately 43% greater than that in the East Malaysia region located in northern Borneo. In contrast, for the region of northern Borneo the semidiurnal power energy spectrum is approximately 25% greater than that in the East Coast of Peninsular Malaysia. This implies that diurnal tides are dominant along the East Coast of Peninsular Malaysia while both diurnal and semidiurnal tides dominate almost equally in coastal East Malaysia. Furthermore, the diurnal tidal energy flux is found to be 60% greater than that of the semidiurnal tides in the southern South China Sea. Based on these model analyses, the significant tidal mixing frontal areas are located primarily off Sarawak coast as indicated by high chlorophyll-a concentrations in the area. PMID:27622552

  5. Tides and Their Dynamics over the Sunda Shelf of the Southern South China Sea.

    Science.gov (United States)

    Daryabor, Farshid; Ooi, See Hai; Abu Samah, Azizan; Akbari, Abolghasem

    2016-01-01

    A three-dimensional Regional Ocean Modelling System is used to study the tidal characteristics and their dynamics in the Sunda Shelf of the southern South China Sea. In this model, the outer domain is set with a 25 km resolution and the inner one, with a 9 km resolution. Calculations are performed on the inner domain. The model is forced at the sea surface by climatological monthly mean wind stress, freshwater (evaporation minus precipitation), and heat fluxes. Momentum and tracers (such as temperature and salinity) are prescribed in addition to the tidal heights and currents extracted from the Oregon State University TOPEX/Poseidon Global Inverse Solution (TPXO7.2) at the open boundaries. The results are validated against observed tidal amplitudes and phases at 19 locations. Results show that the mean average power energy spectrum (in unit m2/s/cph) for diurnal tides at the southern end of the East Coast of Peninsular Malaysia is approximately 43% greater than that in the East Malaysia region located in northern Borneo. In contrast, for the region of northern Borneo the semidiurnal power energy spectrum is approximately 25% greater than that in the East Coast of Peninsular Malaysia. This implies that diurnal tides are dominant along the East Coast of Peninsular Malaysia while both diurnal and semidiurnal tides dominate almost equally in coastal East Malaysia. Furthermore, the diurnal tidal energy flux is found to be 60% greater than that of the semidiurnal tides in the southern South China Sea. Based on these model analyses, the significant tidal mixing frontal areas are located primarily off Sarawak coast as indicated by high chlorophyll-a concentrations in the area. PMID:27622552

  6. Verification of an operational ocean circulation-surface wave coupled forecasting system for the China's seas

    Institute of Scientific and Technical Information of China (English)

    WANG Guansuo; ZHAO Chang; XU Jiangling; QIAO Fangli; XIA Changshui

    2016-01-01

    An operational ocean circulation-surface wave coupled forecasting system for the seas off China and adjacent areas (OCFS-C) is developed based on parallelized circulation and wave models. It has been in operation since November 1, 2007. In this paper we comprehensively present the simulation and verification of the system, whose distinguishing feature is that the wave-induced mixing is coupled in the circulation model. In particular, with nested technique the resolution in the China's seas has been updated to (1/24)° from the global model with (1/2)° resolution. Besides, daily remote sensing sea surface temperature (SST) data have been assimilated into the model to generate a hot restart field for OCFS-C. Moreover, inter-comparisons between forecasting and independent observational data are performed to evaluate the effectiveness of OCFS-C in upper-ocean quantities predictions, including SST, mixed layer depth (MLD) and subsurface temperature. Except in conventional statistical metrics, non-dimensional skill scores (SS) is also used to evaluate forecast skill. Observations from buoys and Argo profiles are used for lead time and real time validations, which give a large SS value (more than 0.90). Besides, prediction skill for the seasonal variation of SST is confirmed. Comparisons of subsurface temperatures with Argo profiles data indicate that OCFS-C has low skill in predicting subsurface temperatures between 100 m and 150 m. Nevertheless, inter-comparisons of MLD reveal that the MLD from model is shallower than that from Argo profiles by about 12 m, i.e., OCFS-C is successful and steady in MLD predictions. Validation of 1-d, 2-d and 3-d forecasting SST shows that our operational ocean circulation-surface wave coupled forecasting model has reasonable accuracy in the upper ocean.

  7. Calcium carbonate pump during Quaternary glacial cycles in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    LIU Zhifei; XU Jian; TIAN Jun; WANG Pinxian

    2003-01-01

    The preservation and dissolution of calcium carbonate (namely calcium carbonate pump) controls the pH of seawater in global oceans by its buffer effect, and in turn plays a significant role in global changes in atmospheric CO2 concentration. The results from measured carbonate contents over the past 2 Ma at ODP Site 1143 in the South China Sea provide high-resolution records to explore the process of the calcium carbonate pump during Quaternary glacial cycles. The results indicate statistically that the highest carbonate accumulation rate leadsthe lightest δ18O by about 3.6 ka at transitions from glacials to interglacials, and that the strongest carbonate dissolution lags the lightest δ18O by about5.6 ka at transitions from interglacials to glacials. The calcium carbonate pump releases CO2 to the atmosphere at the glacial-interglacial transitions, but transports atmospheric CO2 to deep sea at the interglacial-glacial transitions. The adjustable function of the calcium carbonate pump for the deep-sea CO2-3 concentration directly controls parts of global changes in atmospheric CO2, and contributes the global carbon cycle system during the Quaternary.

  8. Studies of upper layer circulations of the South China Sea from Satellite altimeter observation

    International Nuclear Information System (INIS)

    Seventeen years Sea Surface Current (SSC) data from multi-satellite altimeters were used to investigate the upper layer circulation structure over the South China Sea (SCS) . And combined with QuikScat Sea Surface Wind (SSW) data, the relationship between upper layer circulation over SCS and SSW were analyzed. The results show that the largest current velocity and the greatest change of the circulation over the SCS are in the area east of the Indochina Peninsula; There are two main modes of the SCS upper layer circulation, the winter mode from October to next February and the summer mode from June to August. SCS circulations in other months are in the transitional period of the two main modes; Through the correlation analysis of the SSW and SSC, a significant positive correlation, about 0.5, between current and wind was found at the boundary area of the SCS. However, there was a significant negative correlation, about −0.5, near the middle of the SCS. The results also show that the variation of the upper layer circulation structure over the SCS is significant seasonal, and it was mostly dominated by the monsoon

  9. Initial insights into the age and origin of the Kubuqi sand sea of northern China

    Science.gov (United States)

    Yang, Xiaoping; Forman, Steven; Hu, Fangen; Zhang, Deguo; Liu, Ziting; Li, Hongwei

    2016-04-01

    The Kubuqi Desert is the only active sand sea in the semiarid regions of northern China and occurs along the southern margin of the Yellow River. Little is known about the age and origin of this large (17,000 km2) sand sea with a present annual precipitation of 200-480 mm. Sand drift potentials indicated net capable winds for aeolian transport are from the northwest, though winds are stronger to north beyond the dune field than within the sand sea. Geomorphic and stratigraphic observations indicate that Holocene aeolian sand often drapes over bedrock and river terraces as a palimpsest landscape. Field investigations identified four stratigraphic sections with multiple aeolian sand units and palaeosols, with age control by optically stimulated luminescence (OSL) dating of quartz grains. Palaeosols are weakly developed, mostly accumulative A horizon with organic carbon content farming from lost cities in the Kubuqi Desert during the Han (206 B.C. - A.D. 220) and the Tang (A.D. 608 - 907) Dynasties. Also, variable discharge of the Yellow River with local diversions for irrigation and throughout the catchment resulted in possibly an increased supply of aeolian particles for dune field expansion in the past 2 ka.

  10. TYPHOON PROCESS AND ITS IMPACT ON THE SURFACE CIRCULATION IN THE NORTHERN SOUTH CHINA SEA

    Institute of Scientific and Technical Information of China (English)

    TANG Ling; ZHAN Jie-min; CHEN Yi-zhan; LI Yok-sheung; NIE Yu-hua

    2011-01-01

    A severe typhoon Utor, occurring between July 3 and 8, 2001, brought heavy rainfall, strong wind and storm surge. Utor was responsible for tremendous destruction and economic losses in Philippines, Taiwan and Guangdong. An air-sea model system (MM5 and Princeton Ocean Model (POM)) was built to simulate meteorological dynamics and ocean circulation in the South China Sea (SCS). In the POM the output of MM5 was used as the input data. With an increased number of vertical levels, a high-resolution planetary boundary layer scheme and updated landuse/vegetation data, the accuracy of computing wind, temperature and other meteorological fields are improved in near surface and upper levels in MM5 simulations. The simulated trajectory and wind speed of Utor are close to the observed results. The simulated distribution of rainfall is accorded well with measured data in the Pearl River Delta (PRD) area. At different meteorological stations in Hong Kong, the wind, temperature and sea surface pressure are well simulated. The simulated ocean surface current and surface temperature fields have an obvious rightward-biased response to the typhoon Utor, and the maximum velocity and the lowest temperature region appear in the 30 km of the right side of the typhoon track.The typhoon Utor could make the water 50m under the surface ocean unwell to surface and the ocean surface temperature decrease by about 2℃.

  11. Long-range correlations in remotely sensed chlorophyll in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    ZHAN Haigang; SHI Ping; MAO Qinwen; ZHANG Tonghui

    2006-01-01

    A 8-year time series of 8-day Seaviewing Wide Field-of-view Sensor (SeaWiFS) data,which spans from Oct 1997 to Oct 2005, was used to study the temporal correlations and scaling behaviour of ocean chlorophyll fluctuations in the South China Sea (SCS) by means of detrended fluctuation analysis (DFA). Long-range correlations in chlorophyll fluctuations were detected in almost all the SCS. The scaling exponents vary over a wide range from 0.5 to 1.14, with an average value of 0.79. High values are found in the upwelling regions, such as the northwest of Luzon and the north of Sunda Shelf. Low values occur in the southwest of Luzon, the east of Hainan Island and a majority of the southern SCS. This spatial pattern is considerably different from that of the scaling exponents of the sea surface temperature (SST) time series. It is also demonstrated that SST exhibits more persistence than chlorophyll in almost all the SCS.

  12. An abrupt cooling event early in the last interglacial in the northern South China Sea

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The high-resolution quantitative analysis of the planktonic foraminifera and the δ18O records of the section between 96.49-137.6 mcd at ODP Site 1144 on the continental slope ot northern South China Sea reveals an abrupt cooling event of sea surface temperature (SST) dur ing the last interglacial (MIS 5.5, i.e. 5e). The dropping range of the winter SST may come to 7.5℃corresponding to 1.2‰ of the δ18O value of sea surface water. This event is comparable with those discovered in the west Europe and the northern Atlantic Ocean, but expressed in a more intensive way. It is inferred that this event may have been induced by middle- to Iow-latitude processes rather than by polar ice sheet change. Since the Kuroshio-index species Pulleniatina obliquilocu lata displayed the most distinct change at the event, it may also be related to the paleocean ographic change of the Iow-latitude area in the western Pacific Ocean. This event can be consid ered as one of "Younger Dryas-style coolings" and is indicative of climate variability of the last in terglacial stage.

  13. Study on the storm surges induced by cold waves in the Northern East China Sea

    Science.gov (United States)

    Mo, Dongxue; Hou, Yijun; Li, Jian; Liu, Yahao

    2016-08-01

    Cold wave, a kind of severe weather system, can bring strong wind and induce significant sea level rise to the Northern East China Sea. Based on CFSR data, the study shows the monthly distributions of invaded days and the spatiotemporal distributions of cold-wave wind direction and wind speed. A three-dimensional numerical model (ROMS) was developed to study storm surges induced by cold waves. The role of wind direction, wind speed, wind duration, extratropical cyclone and tide-surge interaction is investigated by conducting different sensitivity experiments. The results indicate that storm surges mainly happen at the coasts perpendicular to the wind directions. Surge range and time lag are related to the geometry of the basin and the continental shelf. The response of the sea-level fluctuations to cold wave indicates that there is a positive correlation between crests and wind speed, a negative correlation between troughs and wind speed, but no obvious correlations to wind duration. Coupled weather cold waves, which yield a larger range and a multi-peak structure of surges, can be classified according to cold wave tracks and extratropical cyclones. The tide-surge interaction has an obvious and different effect on the magnitudes and phases of storm surges for different tidal stages.

  14. First record of Thalassiosira curviseriata Takano (Bacillariophyta) and its bloom in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    XIE Wenling; LI Yang; GAO Yahui

    2008-01-01

    A bloom caused by a diatom,Thalassiosira curviseriata Takano (Bacillariophyta),is recorded in the East China Sea for the first time in China during a red tide investigation cruise (MC2005 - 2) from 27 March to 12 April 2005.This bloom was developed with the competition of Chaetoceros debilis and Skeletonema spp.The highest cell density of T.curviseriata,which has reached 1.27 × 106 cells/dm3,was found in the surface and middle water layers of Stss ZD,ZB in the East China Sea (27.22°~29.48°N,121.53°~ 122.98°E)in early spring in 2005.During the blooming period of T.curviseriata,the population with high cell density was found in the water area with temperature of 10 ~ 15 ℃ and salinity of 29.0 ~ 33.5.The percentage of the predominant spe-cies,T.curviseriata,has reached 95.8% of total diatom cells at one time in the middle water layer.The morphological character-istics of T.curviseriata,were observed with light microscope (LM) and transmission electronic microscope (TEM).The cells are 5.0 ~ 12.6 μm in diameter,connecting each other by mucilaginous thread to form spiral and curved chains.Description and LM and TEM images of T.curviseriata are presented.T.curviseriata is ecologically characterized by eurythermy and euryhalinity,and its population variation is affected mainly by silicate,the ratios of phosphorus to silicon and nitrogen to sihcon.

  15. Paleoenvironmental changes in the northern South China Sea over the past 28,000years: A study of TEX86-derived sea surface temperatures and terrestrial biomarkers

    OpenAIRE

    Shintani, Tomoya; Yamamoto, Masanobu; Chen, Min-Te

    2011-01-01

    We have generated a record of TEX86 (TEXH86)-derived sea surface temperatures (SSTs) over the last 28 ka for core MD97-2146 from the northern South China Sea (SCS). The TEXH86-derived temperature of a core-top sample corresponds to the SSTs in warmer seasons. The SST record shows a drop during the Oldest Dryas period, an abrupt rise at the onset of the Bølling–Allerød period, a plateau across the Younger Dryas period, and an abrupt rise at the beginning of the Holocene. The glacial–interglaci...

  16. A wave energy resource assessment in the China's seas based on multi-satellite merged radar altimeter data

    Institute of Scientific and Technical Information of China (English)

    WAN Yong; ZHANG Jie; MENG Junmin; WANG Jing

    2015-01-01

    Wave energy resources are abundant in both offshore and nearshore areas of the China's seas. A reliable assessment of the wave energy resources must be performed before they can be exploited. First, for a water depth in offshore waters of China, a parameterized wave power density model that considers the effects of the water depth is introduced to improve the calculating accuracy of the wave power density. Second, wave heights and wind speeds on the surface of the China's seas are retrieved from an AVISO multi-satellite altim-eter data set for the period from 2009 to 2013. Three mean wave period inversion models are developed and used to calculate the wave energy period. Third, a practical application value for developing the wave energy is analyzed based on buoy data. Finally, the wave power density is then calculated using the wave field data. Using the distribution of wave power density, the energy level frequency, the time variability indexes, the to-tal wave energy and the distribution of total wave energy density according to a wave state, the offshore wave energy in the China's seas is assessed. The results show that the areas of abundant and stable wave energy are primarily located in the north-central part of the South China Sea, the Luzon Strait, southeast of Taiwan in the China's seas; the wave power density values in these areas are approximately 14.0–18.5 kW/m. The wave energy in the China’s seas presents obvious seasonal variations and optimal seasons for a wave energy utilization are in winter and autumn. Except for very coastal waters, in other sea areas in the China's seas, the energy is primarily from the wave state with 0.5 m≤Hs≤4 m, 4 s≤Te≤10 s whereHs is a significant wave height andTe is an energy period; within this wave state, the wave energy accounts for 80% above of the total wave energy. This characteristic is advantageous to designing wave energy convertors (WECs). The practical application value of the wave energy is higher

  17. Numerical Analysis and Simulation Experiment of Lithospheric Thermal Structures in the South China Sea and the Western Pacific

    Institute of Scientific and Technical Information of China (English)

    Lin Ge; Peng Meili; Zhao Chongbin; Zhang Lu; Zhang Desheng; Liu Shilin

    2009-01-01

    The asthenosphere upwelled on a large scale in the western Pacific and South China Sea during the Cenozoic,which formed strong upward throughflow and caused the thermal structure to be changed obviously.The mathematical analysis has demonstrated that the upward throughflow velocity may have varied from 3×1011 to 6×1012 m/s.From the relationship between the lithospheric thickness and the conductive heat flux,the Hthospherie heat flux in the western Pacific should be above 30 mW/m2,which is consistent with the observed data.The huge low-speed zone within the upper mantle of the marginal sea in the western Pacific reflects that the upper mantle melts partially,flows regionally in the regional stress field,forms the upward heat flux at its bottom,and causes the change of the lithospheric thermal structure in the region.The numerical simulation result of the expansion and evolution in the South China Sea has demonstrated that in the early expansion,the upward throughflow velocity was relatively fast,and the effect that it had on the thickness of the lithosphere was relatively great,resulting in the mid-ocean basin expanding rapidly.After the formation of the ocean basin in the South China Sea,the upward throughflow velocity decreased,but the conductive heat flux was relatively high,which is close to the actual situation.Therefore,from the heat transfer point of view,this article discusses how the upward heat flux affects the lithospheric thermal structure in the western Pacific and South China Sea.The conclusions show that the upward heat throughflow at the bottom of the llthospheric mantle resulted in the tectonic deformation at the shallow crust.The intensive uplifts and rifts at the crust led to the continent cracks and the expansion in the South China Sea.

  18. COMPOSITE ANALYSIS OF SUMMER MONSOON ONSET PROCESS OVER SOUTH CHINA SEA

    Institute of Scientific and Technical Information of China (English)

    徐海明; 何金海; 周兵

    2001-01-01

    Based on the method of composite analysis, the onset process and preceding signs of summer monsoon over the South China Sea (SCS) is investigated. The result indicates that convection activities appear first over the Indo-China Peninsula prior to the onset of the monsoon, then around the Philippines just at the point of onset, implying that the convection activities around the Philippines serve as one of the reasons leading to the SCS monsoon onset. Before the SCS monsoon onset, the equatorial westerly over the Indian Ocean (75°E ~ 95°E ) experiences noticeable enhancement and plays an important role on the SCS monsoon onset. It propagates eastward rapidly and causes the establishment and strengthening of equatorial westerly in the southern SCS, on the one hand, it results in the migration southward of the westerly on south side of the south-China stationary front by means of shift northeastward of the westerly and convection over the Bay of Bengal, on the other. Further study also shows that the intensification of equatorial westerly in the Indian Ocean (75°E ~ 95°E) and the southern SCS is closely related to the reinforcement of the Southern-Hemisphere Mascarene high and Australian high, and cross-equatorial flow northward around Somali, at 85°E and 105°E, respectively.

  19. Relation between sea surface temperature anomaly in the Atlantic and summer precipitation over the Northeast China

    Institute of Scientific and Technical Information of China (English)

    白人海

    2001-01-01

    Based on global monthly average data set of sea surface temperature (SST) during 1950 -1992 and global monthly average 500 hPa height during 1950 - 1997 offered by NCAR/NCEP, the feature of SST anomaly in the Atlantic and its relation with summer precipitation over the Northeast China are analyzed. The results show that, the second eigenvector of the SST′s empirical orthogonal expanssion in winter season over the North Atlantic suggests that distribution of SST anomaly has unusual meridional difference; The location of its center is basically identical to center of significant correlation region between summer precipitation over the Northeast China and winter SST in the Atlantic. When winter SST in the North Atlantic is hot in south and cold in north, the blocking situation is stronger in the middle- high latitude. Correspondingly, the blocking high pressure in the northern North Pacific is also getting stronger,the westerlies circulation index in East Asia in next summer would be lower, asa result, more precipitation in the summer would be experienced over Northeast China and vice versa.

  20. Past 140-year environmental record in the northern South China Sea: Evidence from coral skeletal trace metal variations

    International Nuclear Information System (INIS)

    About 140-year changes in the trace metals in Porites coral samples from two locations in the northern South China Sea were investigated. Results of PCA analyses suggest that near the coast, terrestrial input impacted behavior of trace metals by 28.4%, impact of Sea Surface Temperature (SST) was 19.0%, contribution of war and infrastructure were 14.4% and 15.6% respectively. But for a location in the open sea, contribution of War and SST reached 33.2% and 16.5%, while activities of infrastructure and guano exploration reached 13.2% and 14.7%. While the spatiotemporal change model of Cu, Cd and Pb in seawater of the north area of South China Sea during 1986–1997 were reconstructed. It was found that in the sea area Cu and Cd contaminations were distributed near the coast while areas around Sanya, Hainan had high Pb levels because of the well-developed tourism related activities. -- Highlights: • Geochemical behaviors of trace elements in corals from South China Sea were investigated. • Terrestrial input, SST, war and infrastructure explain about 77.4% of elements behaviors in coral. • Changes of trace elements in coral of Xisha Islands were mainly impacted by local activities. • Spatial change of elements in seawater by was evaluated in 1986–1997 using distribution coefficient KD of coral. -- 140-year changes in the trace metals in corals from South China Sea were investigated. The spatiotemporal change model of the metals in seawater was reconstructed using coral record

  1. Study on Precipitation Anomalies of North of China in April and Its relationship to Sea Surface Temperature Evolvement

    Science.gov (United States)

    Song, Y.; Li, Z.; Guan, Y.

    2012-04-01

    Using monthly precipitation data in North of China for 1960-2007, American NCEP/NCAR monthly reanalysis data and NOAA SST (sea surface temperature) data, and SST indices data in Climate System Monitoring Bulletin collected by National Climate Center, this paper studied the general circulation, large-scale weather system anomalous characteristics and SSTA evolvement with more rainfall of North of China in April. The results showed that precipitation differences between months in spring in North of China were quite obvious, and the correlation coefficients between precipitation of North of China in April and that in March and in May were not significant respectively. The linear trend of precipitation in April was out of phase with that in spring. It was meaningful to study precipitation in April solely. The space pattern of first leading mode of EOF analysis for precipitation of North of China in April indicated that rainfall changed synchronously. In years of more rainfall in April showed negative phase of EU pattern in 500hPa geopotential height field of high latitude in the Northern Hemisphere, and North of China located at where cold and warm air masses met, which availed reinforcement of south wind and ascending motion. In middle and high latitudes was latitudinal circulation, and North of China was controlled by warm ridge and latitudinal large-scale front zone; In years of less rainfall, meridional circulation prevailed and large-scale front zone located northward and presented meridional pattern, and North of China was affected by cold air mass. At the same time, water vapor was transported strongly from Pacific, South China Sea and southwest of China, and reached Northeast of China. In years of less rainfall, the water vapor transportation was quite weak. The rainfall was related closely to sea surface temperature anomalies, especially to the Indian Ocean, the middle and east of Pacific, middle and south of Pacific and northwest of Pacific where there were

  2. Diatom assemblages in surface sediments from the South China Sea as environmental indicators

    Institute of Scientific and Technical Information of China (English)

    WU Rui; GAO Yahui; FANG Qi; CHEN Changping; LAN Binbin; SUN Lin; LAN Dongzhao

    2013-01-01

    We studied diatom distribution from 62 samples from the uppermost 1 cm of sediment in the South China Sea (SCS),using grabs or box corers in three cruises between 2001-2007.Fifty six genera,256 species and their varieties were identified.Dominating species included Coscinodiscus africanus,Coscinodiscus nodulifer,Cyclotella stylorum,Hemidiscus cuneiformis,Melosira sulcata,Nitzschia marina,Roperia tesselata,Thalassionema nitzschioides,Thalassiosira excentrica,and Thalassiothrix longissima.Most surface sediments in the SCS were rich in diatoms,except for a few coarse samples.Average diatom abundance in the study area was 104 607 valve/g.In terms of the abundance,ecology,and spatial distribution,seven diatom zones (Zones 1-7) were recognized.Zone 1 (northern continental shelf)is affected by warm currents,SCS northern branch of the Kuroshio,and northern coastal currents; Zone 2 (northwestern continental shelf) is affected by intense coastal currents; Zone 3 (Xisha Islands sea area) is a bathyal environment with transitional water masses; Zone 4 (sea basin) is a bathyal-to-deep sea with stable and uniform central water masses in a semi-enclosed marginal sea; Zone 5 (Nansha Islands marine area) is a pelagic environment with relatively high surface temperature; Zone 6 (northern Sunda Shelf) is a tropical shelf environment; and Zone 7 (northern Kalimantan Island shelf area) is affected by warm waters from the Indian Ocean and coastal waters.The data indicate that these diatom zones are closely related to topography,hydrodynamics,temperature,nutrients and especially the salinity.Better understanding of the relationship between diatom distribution and the oceanographic factors would help in the reconstruction of the SCS in the past.

  3. Phenotypic and genetic characterization of bacteria isolated from diseased cultured sea cucumber (Apostichopus japonicus) in Northeastern China

    Science.gov (United States)

    During the winter–spring from 2004 to 2006 in northeastern China cultured Japanese sea cucumber Apostichopus japonicus suffered from a serious disease. Clinical signs included swollen mouth, skin ulceration and massive mortality. Clinical samples taken during this period were studied. Thirty-one bac...

  4. Two cyclic peptides produced by the endophytic fungus # 2221 from Castaniopsisfissa on the south China sea coast

    Institute of Scientific and Technical Information of China (English)

    Wen Qing YIN; Jie Ming ZOU; Zhi Gang SHE; L. L. P. Vrijmoed; E. B. Gareth Jones; Yong Cheng LIN

    2005-01-01

    New cyclic peptides 1 and 2 were isolated from the endophytic fungus #2221 from Castaniopsisfissa on the south China sea coast. By 2D NMR methods and chiral HPLC technique,their structures were elucidated as cyclo (L-Val-L-Leu-L-Val-L-Leu) and cyclo(L-Leu-L-Ala-L-Leu-L-Ala), respectively.

  5. How economic, strategic, and domestic factors shape patterns of conflict and cooperation in the East China Sea dispute

    DEFF Research Database (Denmark)

    O'Shea, Paul

    2015-01-01

    Despite frequent talk of conflict and even war, economic and strategic factors suggest that the Sino-Japanese dispute over the East China Sea will not erupt into hot conflict, at least for the time being. However, for domestic reasons overt cooperation remains a distant prospect....

  6. Reconstruction of vertical thermal structure from several subsurface temperatures in the China Seas and adjacent waters

    Institute of Scientific and Technical Information of China (English)

    HAO Jiajia; CHEN Yongli; FENG Junqiao; WANG Fan

    2009-01-01

    Empirical Orthogonal Function (EOF) analysis is used in this study to generate main eigenvector fields of historical temperature for the China Seas (here referring to Chinese marine territories) and adjacent waters from 1930 to 2002 (510 143 profiles). A good temperature profile is reconstructed based on several subsurface in situ temperature observations and the thermocline was estimated using the model. The results show that: 1) For the study area, the former four principal components can explain 95% of the overall variance, and the vertical distribution of temperature is most stable using the in situ temperature observations near the surface. 2) The model verifications based on the observed CTD data from the East China Sea (ECS), South China Sea (SCS) and the areas around Taiwan Island show that the reconstructed profiles have high correlation with the observed ones with the confidence level >95%,especially to describe the characteristics of the thermocline well. The average errors between the reconstructed and observed profiles in these three areas are 0.69℃, 0.52℃ and 1.18℃ respectively. It also shows the model RMS error is less than or close to the climatological error. The statistical model can be used to well estimate the temperature profile vertical structure. 3) Comparing the thermocline characteristics between the reconstructed and observed profiles, the results in the ECS show that the average absolute errors are 1.5m, 1.4 m and 0.17℃/m, and the average relative errors are 24.7%, 8.9% and 22.6% for the upper, lower thermocline boundaries and the gradient, respectively. Although the relative errors are obvious, the absolute error is small. In the SCS, the average absolute errors are 4.1 m,27.7 m and 0.007℃/m, and the average relative errors are 16.1%, 16.8% and 9.5% for the upper, lower thermocline boundaries and the gradient, respectively. The average relative errors are all <20%. Although the average absolute error of the lower thermocline

  7. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from Surface underway observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from RYOFU MARU in the Bismarck Sea, East China Sea and others from 1989-11-17 to 1995-03-07 (NODC Accession 0116982)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0116982 includes Surface underway data collected from RYOFU MARU in the Bismarck Sea, East China Sea (Tung Hai), North Pacific Ocean, Philippine Sea,...

  8. Middle and Late Devonian brachiopod assemblages,sea level change and paleogeography of Hunan,China

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Givetian through middle Famennian brachiopods of Hunan are used to define five biozones,comprising,in ascending order,the Stringocephalus Abundance Zone,the Ambocoeliid-Leiorhynchid Assemblage Zone,the Cyrtospiriferid Assemblage Zone,the Yunnanellina-Sinospirifer Assemblage Zone,and the Yunnanella-Hunanospirifer Assemblage Zone.They correspond approximately to the Po.hemiansatus Zone to Po.varcus Zone,S.hermanni Zone to Pa.punctata Zone,Pa.hassi Zone to Pa.linguiformis Zone,Pa.triangularis Zone to Upper Pa.crepida Zone,and Uppermost Pa.crepida Zone to Pa.marginifera Zone,respectively.Intensified rifting activity in South China during the Devonian began in the middle of the Lower Po.varcus Zone(a level marked by the first appearance of Po.rhenanus),which is consistent with the Lower-Middle Givetian substage boundary suggested by the International Subcommission on Devonian Stratigraphy(SDS).This assumed that rifting activity in the Lower Po.varcus Zone was signified by the deposition of the Baqi Formation in Guangxi and was marked largely by the extensive deposition of the Qiziqiao Formation in central Hunan,which probably led to an opposite pattern of relative sea level change-rising in deeper water trough areas and lowering in carbonate platform areas.The previously recognized S.hermanni Zone sea level rise in platform margin areas of Guangxi can be identified not only in the trough areas but also in platform areas,which probably indicates an overall marine transgression at this time,rather than tectonically induced sea level change.Similarly,this level coincides with the Middle-Upper Givetian substage boundary suggested by the SDS.Although the sea level rise may have occurred in the deeper water trough areas of South China towards the end of the Givetian,platformal areas experienced uplifting at various degrees,especially in the central and northern regions of Hunan where Early Frasnian deposits were apparently absent in many places.Similarly,the end

  9. Optimum selection on bridge erection with floating crane in East China Sea Bridge and Hangzhou Bay Bridge

    Institute of Scientific and Technical Information of China (English)

    Shunquan Qin; Pu Zhou; Youheng Hua

    2004-01-01

    @@ Introduction With the rapid development of China′s economy, many bridges will be built over the Chinese coastal waters of Pacific Ocean. Among them, construction of East China Sea Bridge has been commenced in June 2001, and will be completed at the end of 2005, Hangzhou Bay Bridge was also started to construct in June 2003(Fig. 1). These two ultralong bridges are designed as twin expressway bridges standing side by side each carries a 3-lane one-way carriageway. The total width is 31.5m and 33.0m respectively. East China Sea Bridge starts from Nanhui District, Shanghai and extends to the Yangshan Deep Water Port Area, which is located at one of the Qiqu Islands. The total length of the bridge is about 31.0 km, in which 25 km are on the sea, and 22 km is in the unnavigable region. Hangzhou Bay Bridge across the mouth of Qiantang River.

  10. Distribution, historical trends and inventories of polychlorinated biphenyls in sediments from Yangtze River Estuary and adjacent East China Sea

    International Nuclear Information System (INIS)

    A large portion of polychlorinated biphenyls (PCBs) from e-waste released into the coastal areas may be the potential source of PCBs to the global oceans. The paper presents data of PCBs concentrations in fifty surface sediment samples and a dated sediment core in Yangtze River Delta (YRE) and adjacent East China Sea (ECS). The total PCBs levels varied from 5.08 to 19.64 ng/g dry weight, with the highest concentrations situate within the river-sea boundary zone which is so-called “marginal filter”. Concurrent with the operation of e-waste recycling over the last two decades, PCB fluxes started to rise again after 1980s and reached a maximum in this century. The full data set was used to estimate the burden of PCBs in YRE and adjacent ECS. A total sediment burdens were 192.8 tons, with the spatial density of 364 ng/cm2 which accounts for 1.9% of all the PCBs in China. - Highlights: ► PCBs residues remained widespread in Yangtze River Delta and adjacent East China Sea. ► Highest PCBs concentrations situate within the river-sea boundary zone. ► Congener profiles and PCA highlight the influence of e-waste recycling. ► Temporal distributions indicated PCB fluxes reached a maximum in this century. ► Total sediment burdens accounts for 1.9 % of all the PCBs in China. - Spatial and temporal distributions of polychlorinated biphenyls have been delineated in sediments from Yangtze River Estuary and adjacent East China Sea.

  11. Clay minerals in surface sediments of the Pearl River drainage basin and their contribution to the South China Sea

    Institute of Scientific and Technical Information of China (English)

    LIU ZhiFei; Christophe COLIN; HUANG Wei; CHEN Zhong; Alain TRENTESAUX; CHEN JianFang

    2007-01-01

    Clay minerals have played a significant role in the study of the East Asian monsoon evolution in the South China Sea by being able to track oceanic current variations and to reveal contemporaneous paleoclimatic changes prevailing in continental source areas. As one of the most important rivers inputting terrigenous matters to the northern South China Sea, the Pearl River was not previously paid attention to from the viewpoint of clay mineralogy. This paper presents a detailed study on clay minerals in surface sediments collected from the Pearl River drainage basin (including all three main channels,various branches, and the Lingdingyang in the estuary) by using the X-ray diffraction (XRD) method.The results indicate that the clay mineral assemblage consists dominantly of kaolinite (35%-65%),lesser abundance of chlorite (20%-35%) and illite (12%-42%), and very scare smectite occurrences (generally <5%). Their respective distribution does not present any obvious difference throughout the Pearl River drainage basin. However, downstream the Pearl River to the northern South China Sea, the clay mineral assemblage varies significantly: kaolinite decreases gradually, smectite and illite increase gradually. Additionally, illite chemistry index steps down and illite crystallinity steps up. These variations indicate the contribution of major kaolinite, lesser illite and chlorite, and very scarce smectite to the northern South China Sea from the Pearl River drainage basin. The maximum contribution of clay minerals from the Pearl River is 72% to the northern margin and only 15% to the northern slope of the South China Sea. In both glacials and interglacials, kaolinite indicates that the ability of mechanical erosion occurred in the Pearl River drainage basin.

  12. Observations of Earthquake-Generated T-Waves in the South China Sea: Possible Applications for Regional Seismic Monitoring

    Directory of Open Access Journals (Sweden)

    Bor-Shouh Huang

    2013-01-01

    Full Text Available We present a detailed study of T-waves originating from earthquakes in the South China Sea region, near the Indochina Peninsula and Luzon islands which were recorded by a broadband seismic station at Nansha Island. Most of these T-waves appear to have been the source originating from earthquakes with epicentral distances greater than 600 km from this station. The T-waves in this region were identified via their apparent stable measured velocities of about 1.45 km s-1, and represent the first reported T-waves and the first T-waves observed from an island station in the South China Sea. However, during the period of analysis (November 2004 to December 2005 additional earthquakes also occurred beyond the South China Sea region, but in these instances, any associated T-waves were not picked up by the station at Nansha Island. An analysis of T-wave travel times reveals the possible locations of the P-wave to T-wave transitions at the ocean to crust interface were presumably situated near the earthquake source side. Our results indicate that the Sound Fixing and Ranging (SOFAR channel is well developed in the South China Sea region. Ultimately, developing a solid understanding of the effective transmission of T-waves through the ocean may provide new opportunities for detecting and locating small earthquakes which would be useful for both seismic monitoring and in helping to predict and reduce the damaging effects of earthquakes and tsunamis in the South China Sea region.

  13. Modeled connectivity of Acropora millepora populations from reefs of the Spratly Islands and the greater South China Sea

    Science.gov (United States)

    Dorman, Jeffrey G.; Castruccio, Frederic S.; Curchitser, Enrique N.; Kleypas, Joan A.; Powell, Thomas M.

    2016-03-01

    The Spratly Island archipelago is a remote network of coral reefs and islands in the South China Sea that is a likely source of coral larvae to the greater region, but about which little is known. Using a particle-tracking model driven by oceanographic data from the Coral Triangle region, we simulated both spring and fall spawning events of Acropora millepora, a common coral species, over a 46-yr period (1960-2005). Simulated population biology of A. millepora included the acquisition and loss of competency, settlement over appropriate benthic habitat, and mortality based on experimental data. The simulations aimed to provide insights into the connectivity of reefs within the Spratly Islands, the settlement of larvae on reefs of the greater South China Sea, and the potential dispersal range of reef organisms from the Spratly Islands. Results suggest that (1) the Spratly Islands may be a significant source of A. millepora larvae for the Palawan reefs (Philippines) and some of the most isolated reefs of the South China Sea; and (2) the relatively isolated western Spratly Islands have limited source reefs supplying them with larvae and fewer of their larvae successfully settling on other reefs. Examination of particle dispersal without biology (settlement and mortality) suggests that larval connectivity is possible throughout the South China Sea and into the Coral Triangle region. Strong differences in the spring versus fall larval connectivity and dispersal highlight the need for a greater understanding of spawning dynamics of the region. This study confirms that the Spratly Islands are likely an important source of larvae for the South China Sea and Coral Triangle region.

  14. Persistent Heavy Rainfall over South China During May-August:Subseasonal Anomalies of Circulation and Sea Surface Temperature

    Institute of Scientific and Technical Information of China (English)

    洪伟; 任雪娟

    2013-01-01

    This study investigates the relationship between subseasonal variations of the circulation and sea surface temperature (SST) over the South China-East Asian coastal region (EACR) in association with the persistent heavy rainfall (PHR) events over South China during May-August through statistical analysis. Based on the intensity threshold and duration criterion of the daily rainfall, a total of 63 May-June (MJ) and 59 July-August (JA) PHR events are selected over South China from 1979 to 2011. The lower-level circulation anomalies on subseasonal timescale exhibit an anomalous cyclone over South China and an anomalous anticyclone shaped like a tongue over the South China Sea (SCS) during the PHR events for MJ group. The anomalous cyclone over South China in MJ originates from low-value systems in the mid-high latitudes before the rainfall. The anomalous anticyclone over the SCS is due to the westward extension of the western Pacific subtropical high (WPSH) and the southeastward propagation of the anomalous anticyclone from South China before the rainfall. For JA group, the lower-level anomalous circulation pattern is similar to that for MJ over the South China-EACR, but with different features of propagation. The subseasonal anomalous anticyclone is also related to the westward stretch of the WPSH, while the anomalous cyclone is traced back to the weak anomalous cyclone over the Philippine Sea several days before the rainfall events. Positive SST anomaly (SSTA) is observed over the SCS and the Philippine Sea during the MJ PHR events on the subseasonal timescale. It is closely linked with the variation of local anomalous anticyclone. In contrast, negative SSTA occupies the South China coastal region for the JA PHR events, and it is driven by the anomalous cyclone which propagates northwestward from the Philippine Sea. The subseasonal positive (negative) SSTAs are generated via the local processes of above (below)-normal incident solar radiation and below (above

  15. Timing of Holocene sea-level highstands by mass spectro-metric U-series ages of a coral reef from Leizhou Peninsula,South China Sea

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Systematic mass spectrometric 230Th ages are reported for a Porites coral reef terrace from Dengloujiao,Leizhou Peninsula, South China Sea. Seven episodes of coral growth were recognized in this terrace: 7125±96, 6764±29,5826±37, 5006±54, 2543±24, 1915±15, and 1513±22 calendar years before present (cal. aBP). 50% of the coral age population fall between 7200 and 6600 cal. aBP, marking post-glacial stabdization of global sea level. Considering the facts that ( i ) Dengloujiao reef fiat was measured at 1.6-2.5m above modern tidal datum plane; (ii) modern Porites corals in the South China Sea are living at least ~1 m below the modern tidal datum plane; (iii) the top 20-30 cm of the reef was eroded; and (iv) crustal subsidence in the region since mid-Holocene was negligible, we conclude that the above age groups record at least two major periods (7200-5000 and 2500-1500 cal. aBP) of high sea-level at least 2.9-3.8 m above the present-day level.

  16. The rift architecture and extensional tectonics of the South China Sea

    Science.gov (United States)

    Cameselle, Alejandra L.; Ranero, César R.; Barckhausen, Udo; Franke, Dieter

    2016-04-01

    Non-volcanic rifted continental margins are classically described as the product of lithospheric stretching and breakup leading to mantle exhumation, and subsequent seafloor spreading. However, recent studies question this model and indicate a wider range of structural evolutions, that challenge the existing model (e.g. Australia-Antarctic Rift System (Direen et al. 2007, 2011); the Tyrrhenian basin (Prada et al., 2014) or the South China Sea (Cameselle et al. 2015)). Rifting in the South China Sea developed from a series of extensional events, from early Eocene to Late Oligocene, resulting in a V-shape oceanic basin affected by the occurrence of several spreading centers, ridges, transform faults and post-spreading volcanism. In recent years, this marginal basin - the largest in East Asia - has increasingly become one of the key sites for the study of rifting and continental break-up. Its relative small size - compared to many classic, Atlantic-type continental margin settings - allows to easily match conjugated rifted margins and its relative youth promotes the preservation of its original nature. To examine the rifting evolution of the South China Sea, we have reprocessed with modern algorithms multichannel seismic profiles acquired during Sonne49 and BGR84 cruises across the three major subbasins: NW, SW and East subbasins. State-of-the-art of processing techniques have been used to increase the signal to noise ratio, including Tau-P and Wiener predictive deconvolution, multiple attenuation by both radon filtering and wave-equation-based surface-related multiple elimination (SRME) and time migration. To complement seismic interpretation, available vintage multichannel seismic data have been reprocessed with a post-stack flow, including Wiener deconvolution, FK-filtering, space and time variant band-pass filter and time migration. The improving quality of the seismic images shows a range of features including post-rift and syn-rift sediments, the structure of

  17. Wintertime suspended sediment simulation in the Huanghai and East China Seas

    Institute of Scientific and Technical Information of China (English)

    CHOI Byung Ho; MUN Jong Yoon; KO Jin Seok

    2005-01-01

    A simulation of suspended sediment movement relating to tidal and wave forcing during a winter monsoon in November 1983 in the Huanghai and East China Seas continental shelf is attempted by using the model describing the cohesive/non-cohesive sediment resuspension generated by interactions between currents and waves.model simulation showed that sediment concentrafon was increased by resuspension at shallow depths during the strong storm conditions due to high bottom stress interacted between currents and waves.This result is in general agreement with observations in horizontal distribution of suspended sediment distribution.At three current meter mooring positions off the southern Shandong Peninsula resusponsion occurred only at a depth of 22 m,nearest coastal position and at deeper parts at depths of 51 and 80 m wave-current interaction effects were not significant. It has shown that the present model simulation demonstrated the capability of reproduction of suspended sediment movement under wintertime extreme event reasonably well.

  18. Phytoplankton transport to coral reefs by internal solitons in the northern South China Sea

    Science.gov (United States)

    Wang, Yu-Huai

    2016-09-01

    Evidence is presented that waters containing high concentrations of chlorophyll are transported by internal waves to the fore-reef slope of Dongsha Atoll in the northern South China Sea. High vertical resolution mooring measurements of temperature, pressure, and chlorophyll fluorescence revealed that the internal soliton cores could transport chlorophyll vertically downward and increase concentrations by an order of magnitude near the seafloor, compared to background levels. The reef areas that are potentially nourished by the pulses of phytoplankton are dominated by alcyonacean soft corals, while other reef areas that are less or not at all affected by internal waves are dominated by scleractinian hard corals. This suggests that the delivery of phytoplankton by internal solitons provides a plentiful food source that benefits the growth of soft corals.

  19. NUMERICAL STUDY ON THE FORMATION OF THE SOUTH CHINA SEA WARM CURRENT Ⅱ. BAROCLINIC CASE

    Institute of Scientific and Technical Information of China (English)

    王凯; 方国洪; 施心慧

    2001-01-01

    In this part, Levitus' climatological temperature and salinity are incorporated in the numerical model developed in Part I. Diagnostic and prognostic experiment on the thermohaline circulation were conducted. The smooth Levitus' data do not include any information on the South China Sea Warm Current (SCSWC), so it is not in the model-produced diagnostic thermohaline circulation. Although the SCSWC does not appear in the wind-driven circulation in the barotropic case, it appears in the prognostic wind-driven circulation in the baroclinic case. This implies that the differing circulation pat-terns between barotropic case and bareclinic case are due to the stratification. The prognostic thermohaline circulation with wind stress and inflow/outflow transports at open boundaries are also discussed. Coupling of density and dynamic forces makes the circulation pattern more complicated, Even though the stratification is not always a direct cause of the formation of the SCSWC, it is at least an indirect cause.

  20. NUMERICAL STUDY ON THE FORMATION OF THE SOUTH CHINA SEA WARM CURRENT II. BAROCLINIC CASE

    Institute of Scientific and Technical Information of China (English)

    王凯; 方国洪; 施心慧

    2001-01-01

    In this part, Levitus' climatological temperature and salinity are incorporated in the numerical model developed in Part I. Diagnostic and prognostic experiment on the thermohaline circulation were conducted. The smooth Levitus' data do not include any information on the South China Sea Warm Current (SCSWC), so it is not in the model-produced diagnostic thermohaline circulation. Although the SCSWC does not appear in the wind-driven circulation in the barotropic case, it appears in the prognostic wind-driven circulation in the baroclinic case. This implies that the differing circulation patterns between barotropic case and baroclinic case are due to the stratification. The prognostic thermohaline circulation with wind stress and inflow/outflow transports at open boundaries are also discussed. Coupling of density and dynamic forces makes the circulation pattern more complicated. Even though the stratification is not always a direct cause of the formation of the SCSWC, it is at least an indirect cause.``

  1. Barrier layer in the northeastern South China Sea and its formation mechanism

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Robust evidence for the barrier layer (BL) in the northeastern South China Sea (SCS) (16°-25°N, 112°-124°E) is presented. The occurrence rate of the BL peaks in the autumn (45.7%) and then the summer (31.1%) and the spring (23.3%), sequently. It is estimated that the annual occurrence rate of the BL reaches about 40.0% in the central northeastern SCS (18°-22°N, 112°-120°E) and the Luzon Strait. Stratification-formed (Rain-formed) mechanism is the major factor responsible for the occurrence of the BL in the northeastern SCS in the spring (the summer and autumn), respectively. The rainfall observation from TRMM provides reliable evidence for the latter.

  2. Mercury pollution in fish from South China Sea: levels, species-specific accumulation, and possible sources.

    Science.gov (United States)

    Liu, Jinling; Xu, Xiangrong; Yu, Shen; Cheng, Hefa; Hong, Yiguo; Feng, Xinbin

    2014-05-01

    Both total mercury (THg) and methylmercury (MeHg) levels in fish collected from South China Sea (SCS) were studied to understand Hg pollution in Chinese tropical marine ecosystems. The average THg concentrations in fish species ranged from 39.6 μg/kg for rabbitfish (Siganus fuscessens) to 417 μg/kg for thornfish (Terapon jarbua), while those of MeHg varied from 13 μg/kg (rabbitfish) to 176 μg/kg (thornfish). The median values of MeHg/THg ratios in different fish species ranged from 36 to 85%. Significant inter-species differences of THg and MeHg in fish were observed due to feeding habits and fish sizes. Overall, carnivorous fish had higher levels of THg, MeHg and MeHg/THg ratios than omnivorous and herbivorous fish. High Hg levels in fish of the SCS were probably related to Hg input from atmospheric deposition and anthropogenic activities.

  3. Prediction of Scour Depth around Offshore Pipelines in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    Yonggang Cao; Yuchuan Bai; Junqin Wang; Shizhi Liao; Dong Xu

    2015-01-01

    Scour depth prediction of offshore pipelines is of great significance to the design and construction of the submarine pipeline projects. In this paper, based on the CFD software package FLUENT and User Defined Function (UDF), an Eulerian two-phase model, which includes an Euler-Euler coupled model for water and sediment phases, and a turbulent model for the fluid phase, is adopted to predict the scour depth around pipelines. The model is verified by observation data obtained from laboratory experiments. On the basis of the simulations, the factors affecting the scour depth, including the effects of incipient velocity, pipe diameter and sediment particle size and so on, were investigated. Meanwhile, according to formulas of incipient velocity of various sediments, approximate calculation on theoretical scour depths is developed for pipelines of seven stations in the South China Sea, where engineering application information is available.

  4. Prediction of scour depth around offshore pipelines in the South China Sea

    Science.gov (United States)

    Cao, Yonggang; Bai, Yuchuan; Wang, Junqin; Liao, Shizhi; Xu, Dong

    2015-03-01

    Scour depth prediction of offshore pipelines is of great significance to the design and construction of the submarine pipeline projects. In this paper, based on the CFD software package FLUENT and User Defined Function (UDF), an Eulerian two-phase model, which includes an Euler-Euler coupled model for water and sediment phases, and a turbulent model for the fluid phase, is adopted to predict the scour depth around pipelines. The model is verified by observation data obtained from laboratory experiments. On the basis of the simulations, the factors affecting the scour depth, including the effects of incipient velocity, pipe diameter and sediment particle size and so on, were investigated. Meanwhile, according to formulas of incipient velocity of various sediments, approximate calculation on theoretical scour depths is developed for pipelines of seven stations in the South China Sea, where engineering application information is available.

  5. THE RESUSPENSION RATE OF SEDIMENTS IN 32°N SECTION ON THE EAST CHINA SEA

    Institute of Scientific and Technical Information of China (English)

    孙治涛; 詹滨秋

    2002-01-01

    This research on the influence of sediment resuspension on the flux of materials in the margin of the East China Sea showed that the sediment resuspension rates, was 47.40%-79.18% in the surface layers, and 72.75%-96.96% inthe bottom layers.The research confirmed that the Changjiang River runoff and the eddy area upwelling flow near 125°E were two important factors affecting thesediment resuspension in summer; the transformation of DOC to POC through the flocculation in the transitional region (123°-124°E) was also confirmed by comparison of the resuspension rate. The sediment resuspension was shown to be influenced by the seasonal factor, especially in the surface layer.``

  6. Effect of oceanic current on typhoon-wave modeling in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    Cui Hong; He Hai-Lun; Liu Xiao-Hui; Li Yi

    2012-01-01

    We use the WAVEWATCH-Ⅲ model to quantify the effect of oceanic current on typhoon-wave modeling in the East-China-Sea (ECS).Typhoons Jelawat and Saomai in the autumn of 2000 are hindcasted.The oceanic currents in the ECS are mainly constituted of Kuroshio and typhoon-generated currents.The results show distinguishable differences in wave height and wave period under the typhoon conditions.The oceanic current causes the maximum differences,of up to a 0.5 m significant wave height and a 1 s mean wave period.Comparisons between typhoons Jelawat and Saomai show the dependence of the current effect on the typhoon characteristics.

  7. Phylogenetic relationships of South China Sea snappers (genus Lutjanus; family Lutjanidae) based on mitochondrial DNA sequences.

    Science.gov (United States)

    Guo, Yusong; Wang, Zhongduo; Liu, Chuwu; Liu, Li; Liu, Yun

    2007-01-01

    Phylogenetic relationships of intra- and interspecies were elucidated based on complete cytochrome b (cyt b) and cytochrome c oxidase subunit II (COII) gene sequences from 12 recognized species of genus Lutjanus Bloch in the South China Sea (SCS). Using the combined data set of consensus cyt b and COII gene sequences, interspecific relationships for all 12 recognized species in SCS were consistent with Allen's morphology-based identifications, with strong correlation between the molecular and morphological characteristics. Monophyly of eight species (L. malabaricus, L. russellii, L. stellatus, L. bohar, L. johnii, L. sebae, L. fulvus, and L. fulviflamma) was strongly supported; however, the pairs L. vitta/L. ophuysenii and L. erythropterus/L. argentimaculatus were more similar than expected We inferred that L. malabaricus exists in SCS, and the introgression caused by hybridization is the reason for the unexpectedly high homogeneity.

  8. SOME FEATURES OF RING 94S— A KUROSHIO DETACHED EDDY IN THE SOUTH CHINA SEA

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Distributions of current and chemical tracers along two hydrographic sections across Ring 94S, a Kuroshio detached eddy in the South China Sea, were studied. Results suggest that while currents on its offshore side maintained quasi-geostophic, a balance was no reach on its onshore side. It is then suggested that interaction Ring 94S with the slope might play an important role that could break down the quasi-geostrophic balance and caused deformation of the current field. 18 O distribution supports previous discussion that water mass inside the ring is of Kuroshio origin. Distributions of chemical tracer reveal strong “stirring effect” at the edge of Ring 94S, which may play an important role in vertical exchange across the thermocline.

  9. Evaluation of Petroleum System in Xihu Depression, East China Sea Shelf Basin

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    According to the theory of petroleum system and the characteristics of petroleum geology, the Xihu depression in the East China Sea shelf basin is divided into four petroleum systems: the Pinghu Formation as source rock and the Huagang Formation as reservoir rock, the Huagang Formation as source rock and reservoir rock, the Paleocene as source rock and the burial-hill as reservoir rock, and the Miocene as source rock and reservoir rock. The system with the Pinghu Formation as source rock and the Huagang Formation as reservoir rock is the most important one in the depression, which has high hydrocarbon generation and accumulation efficiency and is the most important object to hydrocarbon exploration at present.

  10. A Study on Bottom Friction Coefficient in the Bohai, Yellow, and East China Sea

    Directory of Open Access Journals (Sweden)

    Daosheng Wang

    2014-01-01

    Full Text Available The adjoint tidal model based on the theory of inverse problem has been applied to investigate the effect of bottom friction coefficient (BFC on the tidal simulation. Using different schemes of BFC containing the constant, different constant in different subdomain, depth-dependent form, and spatial distribution obtained from data assimilation, the M2 constituent in the Bohai, Yellow, and East China Sea (BYECS is simulated by assimilating TOPEX/Poseidon altimeter data, respectively. The simulated result with spatially varying BFC obtained from data assimilation is better than others. Results and analysis of BFC in BYECS indicate that spatially varying BFC obtained from data assimilation is the best fitted one; meanwhile it could improve the accuracy in the simulation of M2 constituent. Through the analysis of the best fitted one, new empirical formulas of BFC in BYECS are developed with which the commendable simulated results of M2 constituent in BYECS are obtained.

  11. Bioactive Pregnane Steroids from a South China Sea Gorgonian Carijoa sp.

    Directory of Open Access Journals (Sweden)

    Fei Cao

    2013-03-01

    Full Text Available A new pregnane steroid, 1, and three known analogues 2–4, have been isolated from a gorgonian Carijoa sp. collected from the South China Sea. The planar structure and relative configuration of 1 were elucidated from comprehensive spectroscopic data. Its absolute configuration was determined by application of the modified Mosher method. Compounds 1, 3 and 4 exhibited cytotoxicity against the human hepatoma cell line Bel-7402, with IC50 values of 9.33, 11.02 and 18.68 µM, respectively. Additionally, compound 1 exhibited promising antibacterial activity against Pseudomona puido, with a MIC value of 31 nM, which is approximately 5-fold more potent than ciprofloxacin (MIC = 156 nM.

  12. Bioactive pregnane steroids from a South China Sea gorgonian Carijoa sp.

    Science.gov (United States)

    Zhao, Hong-Ying; Shao, Chang-Lun; Li, Zhi-Yong; Han, Lei; Cao, Fei; Wang, Chang-Yun

    2013-01-01

    A new pregnane steroid, 1, and three known analogues 2-4, have been isolated from a gorgonian Carijoa sp. collected from the South China Sea. The planar structure and relative configuration of 1 were elucidated from comprehensive spectroscopic data. Its absolute configuration was determined by application of the modified Mosher method. Compounds 1, 3 and 4 exhibited cytotoxicity against the human hepatoma cell line Bel-7402, with IC50 values of 9.33, 11.02 and 18.68 µM, respectively. Additionally, compound 1 exhibited promising antibacterial activity against Pseudomona puido, with a MIC value of 31 nM, which is approximately 5-fold more potent than ciprofloxacin (MIC = 156 nM). PMID:23503119

  13. Pseudolella major sp. nov. (Axonolaimidae, Nematoda) from the intertidal zone of the East China Sea

    Science.gov (United States)

    Wang, Chunming; Huang, Yong

    2016-03-01

    A new species of free-living nematode, Pseudolella major sp. nov. is described from the intertidal mudflats of Ximen Island in the East China Sea. Pseudolella major sp. nov. is characterized as follows: body length ~1 300 μm; short cephalic setae, 2-3 μm long; amphidial fovea loop-shaped with elongated ventral branch; ventral branch 50-60 μm long and extending past the base of buccal cavity; buccal cavity cylindrical with arching or spherical base; three heavy outwardly-curving odontia with blunt tips located at anterior of buccal cavity; pharynx short with posterior bulb; ventral gland cell elongate oval-shaped, located posterior to pharyngo-intestinal junction; excretory pore situated at the level of the middle of buccal cavity; tail conical to cylindrical; spicules arched, with double-cephalate proximal end; gubernaculum with a strong dorsal caudal apophysis.

  14. Free polyamine content during algal bloom succession in the East China Sea in spring 2010

    Science.gov (United States)

    Liu, Yan; Zhao, Weihong; Li, Caiyan; Miao, Hui

    2016-03-01

    We measured the concentrations and distribution of major polyamines (spermine, putrescine and spermidine) in seawater during successive spring algal blooms in an area of frequent harmful blooms in the East China Sea. Spermine, putrescine, and spermidine concentrations were analyzed by high performance liquid chromatography and ranged from 1-64, 7-81, and 0-19 nmol/L. Spermine was present at the highest concentrations, followed by putrescine and spermidine. In late April, when a diatom bloom dominated by Skeletonema costatum dispersed, polyamine concentrations increased, presumably as a result of diatom decomposition. In early May, when a dinoflagellate bloom dominated by Prorocentrum donghaiense occurred, the polyamine concentration decreased from the level seen in late April. The abundant polyamines that decomposed and were released during the diatom bloom in late April may have promoted the growth of P. donghaiense, resulting in its dominance.

  15. Carbamate derivatives and sesquiterpenoids from the South China Sea gorgonian Melitodes squamata.

    Science.gov (United States)

    Huang, Li-Si; He, Fei; Huang, Hui; Zhang, Xiao-Yong; Qi, Shu-Hua

    2012-01-01

    Five carbamate derivatives, obtucarbamates C and D (1, 2), dimethyl ((carbonylbis(azanediyl))bis(2-methyl-5,1-phenylene))dicarbamate (3), obtucarbamates A and B (4, 5), and four aromadendrane-type sesquiterpenoids, (+)-4β-N-methenetauryl-10β-methoxy-1β,5α,6β,7β-aromadendrane (6), (-)-4β-N-methenetauryl-10β-methoxy-1β,5β,6α,7α-aromadendrane (7), (-)-4α,10β-aromadendranediol (8), (+)-4β,10β-aromadendranediol (9) were obtained from the South China Sea gorgonian coral Melitodes squamata Nutting. Compounds 1, 2, 6, and 7 were new, and their structures were established by spectroscopic analyses. Compounds 6 and 7 contained a taurine group that was rarely found in marine natural compounds, and 7 showed moderate antibacterial activity. The possible biosynthesis routes of 1-5 were conjectured. PMID:22423284

  16. MARINE BIOFOULING IN OFFSHORE AREAS SOUTH OF HAINAN ISLAND, NORTHERN SOUTH CHINA SEA

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This study on the characteristics of fouling communities in offshore areas south of Hainan Island, northern South China Sea, was conducted at four sites there. At each station, test panels on iron frames were hung on the mooring system at different depths. Data on biofouling were mainly obtained by examination of the fouled test panels. Organisms attached to buoys and anchors were scraped off and examined also. The results showed that the thickness and biomass of marine growth that increased the fluid loading on offshore installations depended to a large extent on hard foulers, i.e. mollusks and acorn barnacles. Algae, hydroids, stalked barnacles and bryozoans were important fouling species. The occurrence frequency and biomass of acorn barnacles decreased with increasing distance from the shore.

  17. Dynamical mechanism of the stratospheric quasibiennial oscillation impact on the South China Sea Summer Monsoon

    Institute of Scientific and Technical Information of China (English)

    ZHENG; Bin; GU; DeJun; LIN; AiLan; LI; ChunHui

    2007-01-01

    The National Center for the Atmospheric Research (NCAR) middle atmospheric model is used to study the effects of the quasi-biennial oscillation in the stratosphere (QBO) on the tropopause and upper troposphere, and the relationship between the QBO and South China Sea Summer Monsoon (SCSSM) is explored through NCEP (the National Centers for Environmental Prediction)/NCAR, ECMWF (European Centre for Medium-Range Weather Forecasts) monthly mean wind data and in situ sounding data. The simulations show that the QBO-induced residual circulations propagate downwards, and affect the tropopause and upper troposphere during the periods of mid-late QBO phase and phase transition. Meanwhile, diagnostic analyses indicate that anomalous circulation similar to SCSSM circulation is generated to strengthen the SCSSM during the easterly phase and anomalous Hadley-like circulation weakens the SCSSM during the westerly. Though the QBO has effects on the SCSSM by meridional circulation, it is not a sole mechanism on the SCSSM TBO mode.

  18. Simulation of barotropic and baroclinic tides in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    WU Ziku; LU Xianqing; TIAN Jiwei

    2005-01-01

    The four leading tidal constituents M2, S2, K1 and O1 in the South China Sea are simulated by using POM. The model is forced with tide-generating potential and four leading tidal constituents at the open boundary. In order to simulate more exactly, TOPEX/Poseidon altimeter data are assimilated into the model and the open boundary is optimized. The computed co-tidal charts for M2 and K1 constituents are generally consistent with previous results in this region. The numerical simulation shows that energetic internal tides are generated over the bottom topography such as the Dongsha Islands, the Xisha Islands, the Zhongsha Islands, the Nansha Islands and the Luzon Strait.

  19. Circulation Patterns of Summer Monsoon Corresponding to Two Kinds of Indices over the South China Sea

    Institute of Scientific and Technical Information of China (English)

    SUN Jilin; WANG Dongxiao

    2002-01-01

    The characteristics of circulation corresponding to two kinds of indices of summer monsoon onset over the South China Sea (SCS) have been discussed using the reanalysis data of the National Centers for Environmental Prediction-National Center for Atmospheric Research. It is found that there are two patterns of deep convection that occur at different locationsand influence the summer monsoon onset over the SCS. One is over the Asia continent and the western Pacific corresponding to the southwesterly of summer monsoon prevailing over the northern and central part of the SCS, while the other is near the Philippines that affects the westerly summer monsoon as prevailing over the central and southern part of the SCS. Since these two kinds of convection affecting the summer monsoon onset do not always occur together, thus the summer monsoon onset time is different when determined by various indices.

  20. Responses of phytoplankton community to the input of different aerosols in the East China Sea

    Science.gov (United States)

    Meng, X.; Chen, Y.; Wang, B.; Ma, Q. W.; Wang, F. J.

    2016-07-01

    Atmospheric deposition can affect marine phytoplankton by supplying macronutrients and trace elements. We conducted mesocosm experiments by adding aerosols with different composition (dominated by mineral dust, biomass burning and high Cu, and secondary aerosol, respectively) to the surface seawater of the East China Sea. Chlorophyll a concentrations were found to be the highest and lowest after adding aerosols containing the highest Fe and dissolved inorganic nitrogen (DIN), respectively. The relative abundance of Haptophyceae increased significantly after adding mineral dust, whereas diatom, Dinophyceae and Cryptophyceae reached the maximum accompanied with the highest DIN. Our results suggest that Fe may be more important than DIN in promoting primary productivity in the sampled seawater. The input of mineral dust and anthropogenic aerosols may result in distinct changes of phytoplankton community structure.

  1. Geophysical Indicators of Gas Hydrate in the Northern Continental Margin, South China Sea

    Directory of Open Access Journals (Sweden)

    Xiujuan Wang

    2011-01-01

    Full Text Available Gas hydrate drilling results show that gas hydrate has a close relationship with strong bottom-simulating reflectors (BSRs identified from seismic data in the Baiyun sag, South China Sea. The BSRs observed on seismic profiles at the crests of submarine canyons indicate the likely existence of gas hydrate. We calculate the acoustic impedance using constrained sparse spike inversion (CSSI, the interval velocity, and the seismic reflection characteristics such as reflection strength, instantaneous frequency, blanking, and enhanced reflection to demonstrate the presence of gas hydrate. Higher acoustic impedance and P-wave velocity were identified above the BSR. A remarkable low impedance, low frequency, and acoustic blanking indicated the presence of gas below gas hydrate stability zone. The occurrence of gas hydrate at the crests of canyons suggests that the abundance of gas hydrate in Baiyun sag may be due to the migrating submarine canyons providing the structural reliefs and the topographic ridges.

  2. Antifouling briarane type diterpenoids from South China Sea gorgonians Dichotella gemmacea

    KAUST Repository

    Sun, Jian Fan

    2013-01-01

    Our continued investigation on the South China Sea gorgonian Dichotella gemmacea led to the isolation of 16 new briarane-type diterpenoids, dichotellides F-U (1-16), along with 18 known analogues (17-34). Their structures were determined by MS, 1D and 2D NMR spectra analyses and by comparison with those reported in literature. The absolute configuration of 15 was confirmed by single-crystal X-ray diffraction data. The antifouling test showed that compounds 3, 4, 6-11, 16, and 23 had potent antifouling activities at nontoxic concentrations with EC50 values of 4.1, 1.82, 6.3, 7.6, 4.6, 1.2, 5.6, 0.79, 2.0, and 0.2 μg/mL, respectively. © 2012 Elsevier Ltd. All rights reserved.

  3. SHORT TIME DYNAMICS OF CILIATE ABUNDANCE IN THE BOHAI SEA (CHINA)

    Institute of Scientific and Technical Information of China (English)

    张武昌; 王荣

    2002-01-01

    The ciliate community in the Bohai Sea (China) was studied from23 September to 7 October 1998. A hurricane struck the study area between the two grid station investigations, which were six days apart. Six tintinnid species(Favella panamensis, Leptotintinnus nordqvisti, Tintinnopsis butschlii, T. karajacensis, T. Radix and Wangiella dicollaria) were identified. Total cililate abundance in the surface layer ranged from 20 to 770 ind/l. In the first grid investigation, Tintinnopsis karajacensis dominated in the warm, low salinity waters at the Huanghe River mouth. Aloricate ciliate sp.1 dominated in the cold, high salinity waters in the northwest of the study area and the Bohai Strait. In the second grid investigation, T. Karajacensis almost disappeared. The abundance of aloricate ciliate sp.1 decreased drastically. The aloricate ciliate sp.2 dominatedat the Bohai Strait. The change of ciliate abundance may be due to the disturbance of hurricane.``

  4. Carbamate derivatives and sesquiterpenoids from the South China Sea gorgonian Melitodes squamata

    Directory of Open Access Journals (Sweden)

    Li-Si Huang

    2012-01-01

    Full Text Available Five carbamate derivatives, obtucarbamates C and D (1, 2, dimethyl ((carbonylbis(azanediylbis(2-methyl-5,1-phenylenedicarbamate (3, obtucarbamates A and B (4, 5, and four aromadendrane-type sesquiterpenoids, (+-4β-N-methenetauryl-10β-methoxy-1β,5α,6β,7β-aromadendrane (6, (−-4β-N-methenetauryl-10β-methoxy-1β,5β,6α,7α-aromadendrane (7, (−-4α,10β-aromadendranediol (8, (+-4β,10β-aromadendranediol (9 were obtained from the South China Sea gorgonian coral Melitodes squamata Nutting. Compounds 1, 2, 6, and 7 were new, and their structures were established by spectroscopic analyses. Compounds 6 and 7 contained a taurine group that was rarely found in marine natural compounds, and 7 showed moderate antibacterial activity. The possible biosynthesis routes of 1–5 were conjectured.

  5. Pleistocene precession forcing of the upper ocean structure variations of the southern South China Sea

    Institute of Scientific and Technical Information of China (English)

    TIAN Jun; WANG Pinxian; CHENG Xinrong

    2004-01-01

    The precession plays a dominant role in driving the tropical monsoon variations. Our high resolution, millennial scale marine isotope records from ODP Site 1143 in the southern South China Sea (SCS) present the detailed history of the upper ocean structure variations over the past 1.56 Ma on glacial/interglacial timescale. The cross spectral analyses between the Earth's orbital variations and the isotopic differences reveal a high coherency between the East-Asian-monsoon-related thermocline and nutricline variations of the SCS and the precession. The variations of monsoon-related isotopic difference between species also demonstrate periodicities of 11-, 12- and 14- thousand years near semi-precession which originates in the tropics, highlighting the importance of the precession in driving the east Asian monsoon changes.

  6. A 200-ka carbon isotope record from the South China Sea

    Institute of Scientific and Technical Information of China (English)

    LI Jianru; WANG Pinxian

    2006-01-01

    A stacked ocean carbon isotope (δ13C)record of 200 ka is established on the basis of planktonic foraminifer (Globigerinoides ruber) δ13C data from 8 sites in the South China Sea (SCS). The δ13C record from the SCS displays a trend similar to that from the Pacific and Atlantic oceans mainly responding to long eccentricity and precession cycles,with all the three δ13C minima occurring at glacial terminations. Thus, the changes of the oceanic carbon reservoir in glacial cycles should not be considered as a response only to ice-sheet variations, but could have been driven also by low latitude processes, such as the monsoon.

  7. Two new species of Hexactinellida (Porifera) from the South China Sea.

    Science.gov (United States)

    Gong, Lin; Li, Xinzheng; Qiu, Jian-Wen

    2015-01-01

    In this paper, two new sponge species, Semperella jiaolongae sp. nov. (Amphidiscosida, Pheronematidae) and Saccocalyx microhexactin sp. nov. (Lyssacinosida, Euplectellidae) are described based on materials from the South China Sea. Semperella jiaolongae sp. nov. is diagnosed mainly by the dermal areas present on both sides of the body, occurring together with atrial areas randomly distributed on one side, and the distinctive shape of micropentactins. Saccocalyx microhexactin sp. nov. is characterized by possession of two types of drepanocomes and one of microhexactins. An analysis based on partial sequence of the 16S rRNA gene was undertaken to show the congruence between morphological identification and phylogenetic classification of the two new species. PMID:26624437

  8. A new diketopiperazine from South China Sea marine sponge Callyspongia sp.

    Science.gov (United States)

    Chen, Yinning; Peng, Yan; Gao, Chenghai; Huang, Riming

    2014-01-01

    Further chemical investigation on the marine sponge Callyspongia sp. collected from South China Sea led to the isolation of a new diketopiperazine, named callysponine A (1), as well as four known diketopiperazines, namely cyclo-(Gly-Pro) (2), cyclo-(Thr-Pro) (3), cyclo-(Ile-Pro) (4) and cyclo-(Pro-Pro) (5). The new structure was determined on the basis of NMR and MS analysis, and the absolute stereochemistry was defined by analysis of the coupling constants and optical rotation. The structures of the known compounds were identified by comparing their spectroscopic data with those reported in the literature. Compounds 1-5 did not inhibit the growth of HepG2 (hepatoma carcinoma cell), A549 (lung carcinoma cell) and HeLa (cervical cancer cell) cell lines.

  9. Chemical Constituents of the Sponge Mycale Sp ecies from South China Sea

    Directory of Open Access Journals (Sweden)

    Xuefeng Zhou

    2013-03-01

    Full Text Available Chemical investigation of the sponge Mycale species from the South China Sea afforded eleven known compounds, henicosanoic acid methyl ester (1 , hexadecyl ethers of glycerol ( 2 , N-docosanoyl-D-erythro-(2S,3R-16-methyl-heptadecasphing-4(E-enine ( 3 , dibutyl phthalate ( 4 , cholesterol ( 5 , 5α,8α-epidioxycholest-6,22-dien-3β-ol ( 6 , 5-hexadecyl-pyrrole-2-carboxaldehyde ( 7 , benzoic acid ( 8 , 4-hydroxybenzoic acid ( 9 , thymine ( 10 ,and uracil ( 11 . Compounds 1 – 4 , 6 – 9 were obtained from the sponge of the genus Mycale for the first time, and 4 and 6 showed toxicity in the brine shrimp lethality test with the LD 50 values at 2.9 μg/mL and 4. 7 μg/mL, respectively .

  10. Spatial variations in the Kuroshio nutrient transport from the East China Sea to south of Japan

    Directory of Open Access Journals (Sweden)

    X. Y. Guo

    2013-04-01

    Full Text Available Based on absolute geostrophic velocity calculated from repeated hydrographic data of 39 cruises from 2000 to 2009 and nitrate concentrations measured at the same sections from 1964 to 2011, we obtained temporally averaged nitrate flux (the product of velocity and nitrate concentration and nitrate transport (integration of flux over a section through 4 sections along the Kuroshio path from the East China Sea (sections PN and TK to south of Japan (sections ASUKA and 137E. In addition, we examined section OK east of the Ryukyu Islands in order to understand the contribution of Ryukyu Current to the Kuroshio nutrient transport south of Japan. The mean nitrate flux shows a subsurface maximum core with a value of 10, 10, 11, 11, and 6 mol m–2 s–1 at sections PN, TK, ASUKA, 137E, and OK, respectively. The depth of subsurface maximum core changes among five sections and is approximately 400, 500, 500, 400, and 800 m at sections PN, TK, ASUKA, 137E, and OK respectively. The mean downstream nitrate transport is 199.3, 176.3, 909.2, 1385.5, and 341.2 kmol m–1 at sections PN, TK, ASUKA, 137E, and OK respectively. The nutrient transports at these sections suggest the presence of Kuroshio nutrient stream from its upstream region to downstream. The deep current structure of Ryukyu Current (section OK makes it contribute more nitrate transport than the Kuroshio in the East China Sea (section TK to the Kuroshio south of Japan. In addition, the positive difference between the downstream nitrate transport through section ASUKA and the sum of nitrate transports through sections TK and OK, as well as the positive difference of downstream nitrate transport between sections 137E and ASUKA, suggest that the Kuroshio recirculation significantly intensifies the downstream (eastward nitrate transport by the Kuroshio.

  11. Ra-226 and Pb-210/Ra-226 Activity Ratio in the Northern South China Sea

    Science.gov (United States)

    Chi-Ju, L.; Yu-Chia, C.; Tsung-En, W.

    2004-05-01

    The surface water distributions and vertical profiles of Ra-226 in the northern South China Sea (SCS) have been measured. Surface water Ra-226 varies between 10 and 16 dpm/100 kg with higher values at stations adjacent to the landmass. Each Ra-226 profile shows an increase from the surface toward the bottom. Above 1000m depth Ra-226 is systematically about 5 dpm/100kg higher in the northern South China Sea than in the western North Pacific. This difference may be attributed to a strong Ra-226 source from the shelf and slope area of the SCS. Below this depth Ra-226 displays large variation within some of the profiles with lower limits being comparable to the activities of the western North Pacific but higher limits being systematically about 5 dpm/100kg higher. These high Ra-226 activities may reflect effects of the longer isolation time for the deep water in the SCS basin and strong Ra input from the underlying sediments. The Pb-210/Ra-226 activity ratio ranges between 1.4 and 2.7 in the surface water with higher activity ratio at the station closer to the Luzon Strait. The Pb-210 in excess over Ra-226 in the surface water due to atmospheric input may penetrate to a depth of about 200 to 500m. Below this depth, Pb-210/Ra-226 activity ratio ranges between 0.5 and 0.7 because Pb-210 is scavenged by settling particulates. Box model calculations within a mixed layer of 50m in the area yield a mean residence time of about 1 yr for Pb-210 if an atmospheric Pb-210 flux of 1 dpm/cm2/y is adopted. The activity ratio of about 0.5 to 0.7 in the deep water corresponds to a Pb-210 mean residence time of about 30 to 70 yrs with respect to particulate scavenging.

  12. Variation in downwelling diffuse attenuation coefficient in the northern South China Sea

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The diffuse attenuation coefficient for downwelling irradiance (Kd(λ)) is an important parameter for ocean studies. Based on the optical profile data measured during three cruises in the northern South China Sea in autumn from 2003 to 2005, variations in the Kd(λ) spectra were analyzed. The variability of Kd(λ) shows much distinct features in both magnitude and spectra pattern, it is much higher in coastal waters than that of open oceanic waters; and the blue-to-green (443/555) ratio of Kd(λ) tends to increase with chlorophyll a concentration ([Chl-a]) from open ocean to coastal waters. These characteristics can be explained most by the increase of aw+p(443)/aw+p(555) with [Chl-a]. In short waveband, the relation between Kd(λ)-Kw(λ) and [Chl-a] can be well described by a power law function, indicating the large contribution of phytoplankton to the variations in Kd(λ). As for the spectral model of the diffuse attenuation coefficient, there are good linear relationships between Kd(490) and Kd(λ) in other wavelengths with own slope and intercept of a linear functions in the spectral range 412-555 nm. Kd(490) is well correlated with the spectral ratio of remote sensing reflectance; and should enough measurement data are given, this empirical algorithm would be used in the Kd(λ) retrieval from ocean color satellite data. The variation in Kd(λ) provides much useful information for us to study the bio-optical property in the northern South China Sea.

  13. Permo-Carboniferous Sequence Stratigraphy and Sea Level Changes in North China Platform

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Through a sequence stratigraphic research on the Permo-Carboniferous in North China, it is suggested that the boundary of the Carboniferous and the Permian may be better moved down to the bottom of the main workable coalbed which is overlain by the limestones containing Pseudoschwagerina zone. This study mainly deals with the Upper Carboniferous, the Lower Permian and the lower part of the Middle Permian coal-bearing strata, which are 150-180 m thick totally and can be divided into 2 mesosequences, including 6 sequence sets and 19 sequences. The lithostratigraphic units are diachronous in North China. The upper two limestones of the Taiyuan Formation in the central part of the study area may be correlated with the bottom two limestones of the lower Taiyuan Formation in the southern part. The Shanxi Formation in the central and northern parts may be correlated with most of the Taiyuan Formation in the southern part. The Xiashihezi Formation in the northern part may be correlated with the upper part of Shanxi Formation in the central and southern parts. The Shangshihezi Formation in the northern part may be correlated with the Xiashihezi Formation in the southern part. The paleogeographical maps are compiled in a chrono-stratigraphic framework. From the Late Carboniferous to the Early Permian, 3 cycles of sea level change and transgression-regression occurred, and the major transgression took place in the Asselian. In the Late Carboniferous, the direction of transgression was from the east to the west, and in the Early Permian it was from the southeast and the southwest to the north. Three workable coalbed groups were formed in Asselian, early Sakmarian and late Sakmarian respectively. The TST coals developed under the bottom of the Asselian limestones are the best coals for coalbed meathane extracting. The Sakmarian coal beds were formed in HST. The coal beds of Lower Permian distribute southward along with the relative sea level falls and sediment progradation.

  14. Experiments in optimizing simulations of the subsurface chlorophyll maximum in the South China Sea

    Science.gov (United States)

    Wang, Siying; Li, Shiyu; Hu, Jiatang; Geng, Bingxu

    2016-04-01

    The subsurface chlorophyll maximum (SCM) is widespread in the oligotrophic ocean and significantly contributes to primary production. One reason for the SCM formation is believed to be the rapid export of phytoplankton from surface layers, which might be caused by aggregation, faster sinking rates under nutrient limitation, or the formation of a resting stage. In this study, these three processes were included in a biological model to investigate their contributions to subsurface chlorophyll. To further identify their individual effects on SCM formation, four modeling experiments were carried out. Three used a simple approach with either (a) density-dependent aggregation, (b) accelerated sinking rate of phytoplankton, or (c) a resting stage. The other experiment combined all three approaches (a-c). A set of observations in the South China Sea was used to optimize the four experiments and compare their abilities to replicate observed values. The results of the experiments with the resting stage showed the best fit to the field observations. All experiments were able to capture major features of the chlorophyll field (e.g. surface bloom and SCM). The experiment with accelerated sinking rate failed to reproduce the observed profile of particulate organic carbon. The experiment with only aggregation predicted lower chlorophyll concentrations in summer than those measured in the field, while experiments with the resting stage reproduced more accurate chlorophyll concentrations. Formulas including the resting stage more successfully captured the timing of phytoplankton export than did those including aggregation and accelerated sinking rate. The processes of aggregation and accelerated sinking rate made small contributions to the SCM formation in the last experiment. Overall, these results show that introducing the resting stage improves SCM simulations of the South China Sea. The results of the experiment with only the resting stage showed that the resting cells shift

  15. Rifted Structure of the Vietnam Continental Margin Near the South China Sea Spreading Center

    Science.gov (United States)

    Reid, I. D.; Fyhn, M. B.; Boldreel, L. O.; Nielsen, L. H.; Duc, N. A.; Huyen, N. T.; Thang, L. D.

    2007-12-01

    The extinct spreading center of the South China Sea intersects the continental margin off Vietnam, providing an excellent opportunity to study the interaction of these two features. As part of a collaborative project between the Geological Survey of Denmark and Greenland, the University of Copenhagen and the Vietnam Petroleum Institute, the crustal structure of this area has been investigated by the use of seismic reflection profiles, to provide control on the sedimentary and basement structure, combined with modelling of gravity data from global satellite altimetry, to constrain the crustal thickness. A complex pattern of rifting is seen, which may be ascribed to the complex stress fields of the propagating rift axis, together with an apparent progression in structure. In the more oceanic area, the rifting is relatively sharp, with fairly rapid crustal thnning of about 10 km. Towards the continent, in the region of the tip of the rift axis, the crustal thinning is less, around 5-7 km, and takes place over a greater distance. In the absence of data on the deep crustal structure it is not possible to determine the absolute crustal thickness with certainty, but the gravity modelling suggests that the pre-existing crust was no more than 20 km thick, having been thinned in earlier stages of formation of the South China Sea. A preliminary analysis of the isostatic balance along the various transects was inconclusive but suggests that the sedimentary sequences are largely isostatically compensated, rather than being supported by lithospheric rigidity. Detailed modelling of the rifting and subsidence may provide further insight into the processes that occur when an oceanic spreading center intersects and propagates into a continental margin.

  16. Microbial biomarkers from the East China Sea and implications for paleoenvironmental reconstructions

    Science.gov (United States)

    Zhao, M.; Hu, W. J.; Duan, S. S.; Cao, L. Y.; Wang, Y. Y.; Zhao, S. Z.; Xing, L.

    2015-12-01

    We report the vertical and spatial distributions of isoprenoid glycerol dibiphytanyl glycerol tetraethers (GDGTs), ladderanes and phytoplankton biomarkers in suspended particulates from the East China Sea (ECS) to evaluate the living habitat and environments of the planktonic archaea Thaumarchaeota and anaerobic ammonium oxidation (anammox) bacteria, respectively. Maximum GDGT concentration mostly occurred in bottom waters while maximum phytoplankton biomarker concentration occurred in the surface layers; and these results from the ECS provides further evidence for the use of the TEX86 index as a proxy for bottom water temperature in shallow shelf sea environments. Ladderanes were detected in both surface and subsurface particulates, suggesting that anammox activity was widespread in both the hypoxia zone near the Changjiang Estuary and in the mid-shelf of the ECS. Thus, anaerobic condition is not a requirement for anammox bacteria; however, ladderane-derived anammox activity was higher in lower oxygen environments, confirming ladderanes as useful proxies for reconstructing hypoxia changes. Statistical analysis will be presented to assess the link between archaea (Thaumarchaeota) performing aerobic ammonia oxidation and bacteria (anammox) performing anaerobic ammonium oxidation in the ECS, the implications for both carbon and nitrogen cycles.

  17. Deep water bottom current deposition in the northern South China Sea

    Institute of Scientific and Technical Information of China (English)

    SHAO Lei; LI XueJie; GENG JianHua; PANG Xiong; LEI YongChang; QIAO PeiJun; WANG LiaoLiang; WANG HongBin

    2007-01-01

    There are some active bottom currents on the northern continental slope of the South China Sea (SCS). Reflection seismic profiles show that the bottom current channels occur in the water depth range of 1000 to 2700 m, extending from the NE to the SW, leading to accumulation of discontinuous drifts with higher sedimentation rates on the eastern side of the channel. The stacking pattern of the layers suggests that these drifts propagated southwestward, following the direction of the bottom currents. One sedimentary drift to the southeast of the Dongsha Islands has the highest sedimentation rate of 97cm/ka in the last 12 ka. The sedimentary characteristics of the sediment layers indicate that these bottom currents are most likley caused by the water movement of a branch of the West Pacific Ocean Current, which enters the northern SCS via the Bashi Strait. Once formed, the bottom currents transport sediments along the northern slope of SCS southwestward and finally disappear into the central basin of the SCS. Due to the bottom current activity, the deep-sea sedimentary process in the northern SCS is complex.

  18. First record of Pantropical spotted dolphins Stenella attenuata in the Yellow Sea, China

    Science.gov (United States)

    Wu, Fuxing; Wang, Xianyan; Zhang, Qiuxia; Miao, Xing; Zhang, Ting; Zhu, Qian

    2015-07-01

    On October 1, 2009, sixteen dolphins were obtained from fishermen by incidental catching in the Yellow Sea, China. As the dolphins' skin color was ambiguous, morphological parameters were measured, and mitochondrial DNA cytochrome b (Cyt b) gene sequence was studied to identify the species. Morphological characteristics were consistent with Pantropical spotted dolphins, Stenella attenuata. Furthermore, a partial mitochondrial DNA cytochrome b (Cyt b) gene sequence as long as 328-bp was studied by extracting genomic DNA from the skins, and six haplotypes were detected in the sixteen dolphins. By comparing homologous sequences available in GenBank (www.ncbi.nlm.nih.gov), all the six haplotypes had maximal genetic similarity with Pantropical spotted dolphin. Eight species of cetacean (whales and dolphins) are now recognised in the Yellow Sea. To the best of our knowledge, this is the first record of Pantropical spotted dolphins from this region. Despite this species being listed as a Grade II National Key Protected Animal since 1988, little is known of its biology in Chinese waters. We recommend remedial research be undertaken to ensure appropriate management.

  19. Winter coastal upwelling off northwest Borneo in the South China Sea

    Institute of Scientific and Technical Information of China (English)

    YAN Yunwei; LING Zheng; CHEN Changlin

    2015-01-01

    Winter coastal upwelling off northwest Borneo in the South China Sea (SCS) is investigated by using satellite data, climatological temperature and salinity fields and reanalysis data. The upwelling forms in Decem-ber, matures in January, starts to decay in February and almost disappears in March. Both Ekman trans-port induced by the alongshore winter monsoon and Ekman pumping due to orographic wind stress curl are favorable for the upwelling. Transport estimates demonstrate that the month-to-month variability of Ekman transport and Ekman pumping are both consistent with that of winter coastal upwelling, but Ek-man transport is two times larger than Ekman pumping in January and February. Under the influence of El Niño-Southern Oscillation (ENSO), the upwelling shows remarkable interannual variability: during winter of El Niño (La Niña) years, an anticyclonic (a cyclonic) wind anomaly is established in the SCS, which behaves a northeasterly (southwesterly) anomaly and a positive (negative) wind stress curl anomaly off the north-west Borneo coast, enhancing (reducing) the upwelling and causing anomalous surface cooling (warming) and higher (lower) chlorophyll concentration. The sea surface temperature anomaly (SSTA) associated with ENSO off the northwest Borneo coast has an opposite phase to that off southeast Vietnam, resulting in a SSTA seesaw pattern in the southern SCS in winter.

  20. Biodiversity of free-living marine nematodes in the southern Yellow Sea, China

    Science.gov (United States)

    Liu, Xiaoshou; Xu, Man; Hua, Er; Zhang, Zhinan

    2016-02-01

    Biodiversity patterns of free-living marine nematodes were studied using specific, taxonomic and phylogenetic diversity measures in the southern Yellow Sea, China. The results showed that the average of Shannon-Wiener diversity index ( H') in the study area was 3.17. The higher values were distributed in the east part of Shandong coastal waters and north part of Jiangsu coastal waters, while the lower values were distributed in the southern Yellow Sea Cold Water Mass (YSCWM). The average of taxonomic diversity ( Δ) was 62.09 in the study region. The higher values were distributed in the transitional areas between the coastal areas and the southern YSCWM, while the lower values were distributed near the north part of Jiangsu coastal waters and the YSCWM. Results of correlation analysis of species diversity and taxonomic diversity showed that some of the two kinds of diversity index were independent, which suggested that combining the two kinds of diversity indices can reflect the ecological characteristics better. A test for 95% probability funnels of average taxonomic distinctness and variation in taxonomic distinctness suggested that Station 8794 (in the YSCWM) was outside of the 95% probability funnels, which may be due to the environmental stress. Results of correlation analysis between marine nematodes biodiversity and environmental variables showed that the sediment characteristics (Mdø and Silt-clay fraction) and phaeophorbide a (Pha- a) were the most important factors to determine the biodiversity patterns of marine nematodes.