CYCLONIC RECIRCULATION ON THE LEFT SIDE OF THE KUROSHIO IN THE EAST CHINA SEA

1 .　ＩＮＴＲＯＤＵＣＴＩＯＮＫｕｒｏｓｈｉｏｅｎｔｅｒｓｔｈｅＥａｓｔＣｈｉｎａＳｅａ (ＥＣＳ)ｅａｓｔｏｆＴａｉｗａｎａｎｄｆｌｏｗｓａｌｏｎｇｔｈｅｓｈｅｌｆｅｄｇｅｉｎｔｈｅＯｋｉ ｎａｗａＴｒｏｕｇｈｕｎｔｉｌａｒｏｕｎｄ 2 9°30′Ｎ ,ｗｈｅｒｅｉｔｓｅｐａ ｒａｔｅｓｆｒｏｍｔｈｅｓｈｅｌｆａｎｄｒｅｅｎｔｅｒｓｔｈｅＰａｃｉｆｉｃＯｃｅａｎｔｈｒｏｕｇｈｔｈｅＴｏｋａｒａｓｔｒａｉｔ.Ｉｔａｆｆｅｃｔｓｄｉｒｅｃｔｌｙｔｈｅｏｕｔｅｒｓｈｅｌｆｃｉｒｃｕｌａｔｉｏｎａｎｄｔｈｅｒｍｈａ…     

DYNAMICS OF THE KUROSHIO INTRUSION INTO THE SOUTHEAST CHINA ADJACENT WATERS-A NUMERICAL STUDY

1 .　ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｗｅｓｔｗａｒｄｉｎｔｒｕｓｉｏｎｏｆｔｈｅＫｕｒｏｓｈｉｏｏｃｃｕｒｓｉｎｔｈｅＬｕｚｏｎＳｔｒａｉｔａｎｄｏｆｆＴａｉｗａｎｎｏｒｔｈｅａｓｔｃｏａｓｔ.Ｔｈｅｂｅｈａｖｉｏｒｓａｎｄｓｔｒｕｃｔｕｒｅｓｏｆｔｈｅｉｎｔｒｕｄｉｎｇｆｌｏｗｓｈａｖｅｂｅｅｎｓｔｕｄｉｅｄｂｙｍａｎｙｏｃｅａｎｏｇｒａｐｈｅｒｓ ,ｙｅｔｎｏｔｆｕｌｌｙｋｎｏｗｎ .Ｔｈｅｄｙｎａｍｉｃａｓｐｅｃｔｓｏｆｔｈｅｉｎｔｒｕｓｉｏｎｈａｖｅｂｅｅｎｓｔｕｄｉｅｄｂｙｆｅｗｉｎｖｅｓｔ…     

SIMULATION OF GENERAL CIRCULATION IN THE EAST CHINA SEA AND THE YELLOW SEA

Based on a three-dimensional primitive equation dynamic numerical mod-el,the general circulation in the East China Sea and the Yellow Sea is studied with a O.25°×0.25°horizontal grid and a realistic bottom topography.As the first step,we con-sider the tidel current and Kuroshio(Japan current).The main results are:1)the modeltidal harmonic constants agree surprisingly well with the observations at the 81 coastlinestations in this area.The average amplitude difference is 1.7cm and the average phase dif-ference is 5.2°for the diurnal component,and those for the semi-diurnal tide 4.1 cm and3.7 °2)the path of the Kuroshio agrees with long—term observations; 3)after enteringthe studied area, a branch of the Kuroshio enters the East China Sea.This pattern agreeswith the nation-wide comprehensive ocean investigations; 4)a branch of the Kuroshiogoes northward and forms the Tsushima warm current,and the origin of Tsushima warmcurrent is multi-source.In the Tsushima Strait,the warm current goes into the Sea o     

THE EFFECT OF KUROSHIO ON THE CIRCULATION IN CHINA SEAS-FROM SATELLITE-TRACKED DRIFTER DATA

1 .　INTRODUCTIONTherearethreeintrusionsoftheKuroshioonthecirculationintheChinaseas :theintrusioninLuzonStrait ,theintrusionnorthtoTaiwanIslandandtheintrusionwesttotheJanpan .Thethreein trusionsarerespectivelystudiedusingsatellite trackeddrifterdatafromMEDS .2 .　DATAThedriftingbuoyrecordsofthedatasetinthisstudyareprovidedbyMEDS .BythestandardsofWOCE/TOGA ,allthedrifterswereinitiallyat tachedtodroguesorseaanchorscenteredat 15mdepthstosecureadequatewater followingbehavior(Hansen…     

THE EFFECTS OF MONSOONS AND CONNECTIVITY OF SOUTH CHINA SEA ON THE SEASONAL VARIATIONS OF WATER EXCHANGE IN THE LUZON STRAIT

Seasonal variations of water exchange in the Luzon Strait are studied numerically using the improved Princeton Ocean Model (POM) with a consideration of the effects of connectivity of South China Sea (SCS) and monsoons. The numerical simulations are carried out with the strategy of variable grids, coarse grids for the Pacific basin and fine grids for the SCS. It is shown that the Mindoro Strait plays an important role in adjusting the water balance between the Pacific and the SCS. The SCS monsoon in summer seasons hinders the entrance of the Pacific water into the SCS through the Luzon Strait while the SCS monsoon in winter seasons promotes the entrance of Pacific water into the SCS through the Luzon Strait. However, the SCS monsoon does not affect the annual mean Luzon Strait transport, as is mainly determined by the Pacific basin wind.     

THE INTRUSION AND INFLUENCES OF INTRASEASONAL LONG ROSSBY WAVES IN THE EAST CHINA SEA

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 Rosshy 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 passingIslands are relative weak and Kuroshio variation.through the gaps of Ryukyu have negligible effects on the Kuroshio variation.     

NUMERICAL SIMULATION OF SUMMER CIRCULATION IN THE EAST CHINA SEA AND ITS APPLICATION IN ESTIMATING THE SOURCES OF RED TIDES IN THE YANGTZE RIVER ESTUARY AND ADJACENT SEA AREAS

Based on the COHERENS (a Coupled Hydrodynamical Ecological model for Regional Shelf seas), a three-dimensional baroclinic model for the summer of East China Sea (ECS) was established with the sigma-coordinate in the vertical direction and spherical coordinate in the horizontal direction. The circulation patterns of the Kuroshio Current, the Taiwan Warm Current (TWC), the Tsushima Current and the Yangtze Diluted Water (YDW) were successfully simulated with this model. The calculated results are fairly consistent with previous observations and studies. Based on this baroclinic current field, the Lagranian particles tracking was simulated to estimate the possible origins of the red tides frequently occurring in the Yangtze River estuary and its adjacent sea areas. If there are “seeds” (cysts) of the red tide algae at the seabed of the Taiwan Strait, the offshore of Fujian and Zhejiang Provinces and the northeast Taiwan Island, those are extremely possible sources of the red tides in the Yangtze River estuary and its adjacent sea areas. Field data are needed to confirm it. Numerical simulation to estimate the source of the red tides is a new application of the Lagrangian transport in the marine ecology.     

THE STUDY OF THE YELLOW SEA WARM CURRENT AND ITS SEASONAL VARIABILITY

The Yellow Sea Warm Current (YSWC) penetrates northward along the Yellow Sea Trough, and brings warm and saline water towards the Bohai Sea. The YSWC becomes much less intrusive in summer and is limited mostly in the southern trough, contrasting with a deep winter penetration well into the trough. The seasonal variability of the YSWC has prompted a debate regarding which controls the YSWC and its seasonal variability. In this article, the annual mean and seasonal variability of the YSWC was examined by using a 3-D ocean model together with several experiments. The results show that in the annual mean the YSWC is a compensating current firstly for the southward Korea Coastal Current (KCC), which is mainly caused by the Kuroshio Current (KC). The local wind-stress forcing plays an important but secondary role. However, the local monsoonal forcing plays a prominent role in modulating the seasonal variability. A deep northwestward intrusion of the YSWC in winter, for instance, is mainly due to a robustly developed China Coastal Current (CCC) which draws water along the Yellow Sea trough to feed a southward flow all the way from the Bohai Sea to the Taiwan Strait.     

TYPHOON PROCESS AND ITS IMPACT ON THE SURFACE CIRCULATION IN THE NORTHERN SOUTH CHINA SEA

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°C.     

NUMERICAL SIMULATION OF TOPOGRAPHY CHANGE IN RECLAIMED LAND ALONG COAST OF SOUTH CHINA SEA

1. INTRODUCTIONThe geomorphology of beach is controlled by natural and unnatural effects. In coastal reclaimed land, the topography change is based on suspended sediment transport and near-bed sediment transport. No matter whether the topography change is…     

MODELING OF WATER DYNAMICS AND POLLUTANT SPREADING IN THE LUOMAHU RESERVOIR FOR WATER TRANSFER FORM SOUTH TO NORTH OF CHINA

1 .　ＩＮＴＲＯＤＵＣＴＩＯＮＷａｔｅｒＴｒａｎｓｆｅｒＦｒｏｍＳｏｕｔｈＴｏＮｏｒｔｈＰｒｏｊｅｃｔ(ＷＴＦＳＴＮＰ)ｉｓａｇｒｅａｔｄｅｃｉｓｉｏｎｔｏｓｏｌｖｅｔｈｅｐｒｏｂｌｅｍｏｆｗａｔｅｒｓｈｏｒｔａｇｅｉｎｔｈｅｎｏｒｔｈａｎｄｃｅｎｔｒａｌｐａｒｔｓｏｆＣｈｉ ｎａ .Ｔｈｉｓｐｒｏｊｅｃｔ ,ｉｎｃｌｕｄｉｎｇＥａｓｔ ,Ｃｅｎｔｒａｌ ａｎｄＷｅｓｔ Ｌｉｎｅ ,ｗｉｌｌｄｒａｗｗａｔｅｒｆｒｏｍｔｈｅＹａｎｇｔｚｅＲｉｖｅｒｔｏｔｈｅｎｏｒｔｈａｎｄｃｅｎｔｅｒｏｆＣｈｉｎａｓｏｔｈａ…     

INTERANNUAL VARIABILITY OF KUROSHIO CURRENT AND ITS EFFECT ON THE NEARSHORE BRANCH IN JAPAN/EAST SEA

Based on the Hybrid Coordinate Ocean Model (HYCOM), this article presents simulations of the three-dimensional dynamic and thermal structure of the North Pacific Ocean (NPO) in the time domain from January 1991 to December 2000. The baroclinic current field and its interannual variability in Northwest Pacific Ocean (NWPO), especially, the Kuroshio Current (KC) and the Japan/East Sea (JES) are analyzed and discussed. The results show that the HYCOM covers a complete dynamic and thermo process with adequate representations of the eddy fields and variability in main spatial and temporal scales. The model is used to simulate the strong interanual variability of the KC, which may affect the strength of the eastern bifurcation of the Tsushima Warm Current (TSWC), named the Nearshore Branch (NB) in the JES. When the KC is strong and its axis is close to the Japan Island, the TSWC and its bifurcations in the JES would intensify accordingly. Our results confirm once again the hypothesis of Yang et al. that the KC determines the annual mean NB in the JES via the “island integral constraint”. This article further extends this hypothesis to study the KC role in the NB on a time dependent scale.     

WATER QUALITY MODELING AND POLLUTION CONTROL FOR THE EASTERN ROUTE OF SOUTH TO NORTH WATER TRANSFER PROJECT IN CHINA

1.INTRODUCTION South to North Water Transfer Project in Chinais designed to solve water shortage problem and support sustainable social and economic development in northern China.Eastern Route Project(ERP)is one of the three components of the water transfer project.Pumping water from the Yangtze River in Yangzhou,Jiangsu Province,ERP utilizes the Grand Canal and its parallel rivers to transfer water from south to north.It also employs Hongze Lake,Huoma Lake,Nansi Lake and Dongp…     

SEASONAL REVERSE OF SEA SURFACE SLOPE IN THE NORTHERN YELLOW SEA AND ITS DYNAMIC RELATION WITH MONSOON EFFECTS

Based on the monthly average sea level data from the tide gauge measurement (1999-2001), the seasonal variability of the sea level in the Northern and Middle Yellow Sea is studied to reveal that the sea surface height at all the tide gauges becomes higher in summer than that in winter. In addition, the sea surface height of the Northern Yellow Sea is higher than the one of the Middle Yellow Sea with a slope downward from the north to the south in summer, while it is lower with a reversed slope in winter. The seasonal reverse of the sea surface slope can be attributed to the monsoon effects i.e. the annual reverse of the monsoon direction and the annual variation of the monsoon rainfall. A set of equations are established in light of the dynamic principles to expound how the monsoon forcing and the sea surface slope generate a summer outflow and a winter inflow in the Yellow Sea.     

REEXAMINATION OF THE ROLE OF VERTICAL CIRCULATION IN SEDIMENTATION IN THE YELLOW AND EAST CHINA SEAS

1 .　ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｒｅａｒｅｔｈｒｅｅｂｉｇｒｉｖｅｒｓｔｈｅＹｅｌｌｏｗ ,ＹａｎｇｔｚｅａｎｄＰｅａｒｌｒｕｎｎｉｎｇｆｒｏｍｔｈｅｃｏｎｔｉｎｅｎｔｏｆＣｈｉｎａｔｏＣｈｉｎａＳｅａｓ.ＴｈｅＹｅｌｌｏｗＲｉｖｅｒｅｍｐｔｉｅｓｓｅｄｉｍｅｎｔｔｏｔｈｅＢｏｈａｉＳｅａｗｉｔｈａｎａｍｏｕｎｔｏｆ 0 .7× 1 0 9ｔｏｎｓｐｅｒｙｅａｒ (Ｈｕｅｔａｌ.1 998ａｎｄＰａｎｇｅｔａｌ.1 999)ｗｉｔｈａｈｉｓｔｏｒｉｃａｎｎｕａｌｍｅａｎｏｆ 1× 1 0 9ｔｏｎｓ (Ｘｉｅｅｔａｌ.1 980 ;Ｍｉｌ…     

URBANIZATION IMPAIRS SURFACE WATER QUALITY: EUTROPHICATION AND METAL STRESS IN THE GRAND CANAL OF CHINA

Rapid urbanization leads to degradations upon water quality via eutrophication and pollution, but there are a lack of studies on patterns of water quality change to urbanization by level or process. China has achieved the most rapid urbanization in the world within the past three decades, and its urban development is diverse at level. Nine towns and cities at various development levels along the historic Grand Canal (approximately 1500 years old) were selected to reveal direct linkages between surface water quality and extent of urbanization. Surface water quality in the urban sections of the Grand Canal was impaired by both eutrophic nitrogen and phosphorus and metals. Although metals mostly remained at concentrations permissible to the Chinese National Environmental Standard for Surface Water Quality (GB3838‐2002), the concentrations of metals in most urban canal water might impose an unacceptable effect on aquatic communities according to the Criterion Continuous Concentration from the National Recommended Water Quality Criteria for Priority Toxic Pollutants (US EPA 2006). The loadings of metals in the urban canal were found relating to local industrial activities. The level of urbanization, in this study, was significantly related to water quality parameters in a descending order of electrical conductivity > nutrients > metals. This study suggests that significant mitigation strategies are required for the Grand Canal of China for a sustainable urbanization goal. Copyright © 2011 John Wiley & Sons, Ltd.     

MATHEMATICAL MODELING OF OIL SPILL ON THE SEA AND APPLICATION OF THE MODELING IN DAYA BAY

Through the study of the theory of oil spill model, a mathematical modeling of oil spill on the sea is developed which with the consideration of spread, diffusion, drifting and attenuation of oil slick is influenced by evaporation and emulsification factors. A model that under the effect of ocean dynamic condition of tide, wind and wave, using Monte Carlo method to simulate the movement of oil slick is established. The modeling is applied to calculate and predict pollution range of oil spill at oil quay and oil ship in Daya Bay. The prediction results have basically shown the pollution situation by emergency of oil spill on the sea.     

STUDY ON THE WIND AND WAVE EXTREME PARAMETERS OF TONKIN GULF IN THE SOUTH CHINA SEA-THE APPLICATIONS OF LAGFD NUMERICAL MODELS

Based on the hindcast of the severest 75 tropical cyclones (hereafter is called TCs) which affected Tonkin Gulf in history, the present paper gives sea surface wind and wave extreme parameters at 38 points corresponding to (1/2)×(1/2)?grid in the Gulf. The research increases our understanding of the meteo-ocean conditions on the whole area and provides basic data for ocean environmental research and engineering design.     

FINITE ELEMENT NUMERICAL SIMULATION FOR THE HYDRODYNAMIC FIELD EVOLUTION OF GEOTHERMAL WATER IN THE NANWENQUAN ANTICLINE IN CHONGQING IN CHINA

1. INTRODUCTION The Nanwenquan anticline is the drape storing geothermal water. The anticline extends from north to south in Chongqing, the Nanwenquan and Xiaoquan in the middle of the anticline [1]. The two hot springs, and geothermal water in the other …     

位山穿黄探洞应急加固工程大堤安全监测仪器安装埋设、观测及分析

介绍南水北调东线穿黄探洞应急加固工程大堤安全监测项目中测斜管、位移计、测压管等观测仪器的安装埋设、观测方法 ,并对所获得的观测资料进行初步的整理分析