长江感潮河段潮波传播变化特征及影响因素分析

径潮相互作用是感潮河段水动力变化的典型特征，受其影响潮波传播具有明显的洪枯季及沿程变化。本文基于长江感潮河段天生港、江阴、镇江、南京、马鞍山及芜湖6个潮位站2002?2014年连续高低潮位资料及大通站月均流量数据，统计分析长江感潮河段潮波振幅衰减率、潮波传播速度及余水位坡度等传播特征值的洪枯季及沿程变化特征，并探讨这些潮波传播特征的变化规律及其主要影响因素。结果表明，潮波传播特征的洪枯季差异自上游至下游逐渐减小，其分界点位于天生港与江阴之间（其中，天生港和江阴站的多年平均洪枯季潮差差值约为0.01 m和?0.04 m）；径流动力对潮波衰减的影响主要位于江阴以上河段，江阴以下河段主要受潮汐动力控制；径流驱动下余水位坡度引起的余水位及水深增加，导致潮波传播的有效摩擦减小，当流量超过某个阈值时潮波振幅衰减反而减弱，特别是上游马鞍山-芜湖段最为明显，统计结果表明该河段流量阈值约为33 000 m3/s。本文分析结果作为前人研究的重要补充，可为长江河口感潮河段径潮相互作用机制研究及河口治理等提供基础参考。     

珠江河网横向汊道水位演变特性及原因探究

珠江河网横向汊道体系是维持三角洲河网动力平衡的独特地貌结构,具有泄洪纳潮的重要功能,探讨该结构水位的阶段性演变及其影响因子辨识是河口动力学研究的重要科学问题。采用流量驱动的R＿TIDE数据驱动模型,对研究区域内“容桂-凫洲水道”和“潭洲-前航道”两个典型横向汊道体系共8个站点的日均水位序列进行分解,分离出由上游流量驱动引起的水位变化及地形和海平面共同驱动的水位变化。结果表明,经过水库的调蓄作用,在“容桂-凫洲水道”,流量驱动导致冬季日均水位抬升(平均为0.04m),其余三季日均水位下降;“潭洲-前航道”则由于北江流量增大导致流量驱动的日均水位均有不同程度的抬升(平均为0.17 m)。由于地形下切和海平面上升,地形和海平面共同驱动的日均水位变化普遍为负值(除南沙、黄埔站分别为0.11、0.07 m),“容桂-凫洲水道”中下部河段在秋季受海平面上升(秋季海平面高程最大)影响大于河床地形下切效应导致水位抬升,而其余站点主要受到疏浚、采砂等人类活动引起的地形下降影响,水位下降,且上游变化幅度明显大于下游;对径潮动力方差贡献率的分析结果表明,“容桂-凫洲水道”和“潭洲-前航道”夏季径流对水位的方...     

浙江沿岸海平面变化的初步研究

本文对浙江沿岸海平面变化研究中的若干问题进行了分析和讨论,结果表明:浙江沿岸海面形状较平坦。海平面变化呈上升趋势,在过去的30～33年间,用长涂、镇海和坎门站长期潮位资料分析,海平面年上升速率为2.3mm/a。预测今后几十年间浙江沿岸海平面处在一个上升时期。     

基于EOF法的长江口高潮位时空变化特征研究——长时间序列的高潮位EOF分析

根据长江口6个主要潮位站1993-2008年潮位资料,通过经验正交函数分析法(EOF法)分析了长时间序列和三峡工程前后月平均高潮位变化规律以及2000年的日高潮位变化规律,并探究其影响因素。结果表明:EOF分析前三个主成分贡献率为98.19%,可以反映潮位变化的主要过程。EOF1的影响因子是径流量,在空间上均为正值,呈上游至下游递减趋势,时间系数呈季节性变化;EOF2的影响因子是月平均海平面变化,在空间上有明显的分布差异,时间系数总体有上升趋势。三峡工程前后影响因子的作用有一定变化,径流量的影响增强,海平面减小。徐六泾以上河段的潮位站受径流丰枯影响,徐六泾以下高潮位受平均海平面控制更大。     

渤海潮汐和风暴潮分离的研究

根据渤海10个站和大连、烟台共12个站同步一年的潮汐资料,采用调和分析和响应分析方法,分离出逐时的增减水.计算表明,对大多数海港,依据两种方法得到的增减水量值是一致的,对于非线性效应明显的港口,两者的结果相差较大.同时,还分析了渤海几次较强增减水过程的变化规律.     

南海周边相对海平面变化特征及2004年苏门答腊地震影响分析

利用南海周边1989-2014年的潮汐资料和GPS长期观测资料,分析了南海周边相对海平面变化特征,以及2004年苏门答腊地震对该区域相对海平面变化的影响。研究结果表明,南海周边的相对海平面变化以上升为主,平均上升速率（4.53±0.20） mm/a,高于全球平均速率,且2004年后上升趋势加剧;南海周边相对海平面呈现6类较典型的变化特征,并存在与板块构造相对应的分区聚集现象,形成了中国东南和越南沿海、马来半岛、加里曼丹岛北部、菲律宾群岛等4个变化特征区。受2004年苏门答腊大地震的影响,马来半岛、南沙和西沙海域的地壳形变由上升趋势转为下沉,加剧了相对海平面的上升;中国东南沿海和菲律宾群岛受地震影响较小;越南沿海和加里曼丹岛北部区域的地震影响还有待进一步研究。     

中国东海海平面长期变化与趋势研究

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.     

Expected changes in the benthic fauna of Wadden Sea tidal flats as a result of sea-level rise or bottom subsidence

In different parts of the Dutch Wadden Sea, relationships between intertidal level and abundance of marine macrozoobenthos were similar. Numerical densities, biomass and species richness increased from values close to 0 at the high-water level to maximum values around mean-tide level (numbers) or halfway between this level and low-tide level (biomass). Species richness hardly declined below mean-tide level, whereas mean weight per individual continued to increase from high- to low-water level.Biomass was about 45 g ash-free dry weight per m² at its maximum and declined in an approximately linear way to values close to 0 at the high-water level and to about 7 g per m² at the low-water level. These two linear relationships were used to predict biomass changes on intertidal flats of the Wadden Sea at various scenarios of sea-level rise and bottom subsidence. Net sea-level rise is expected to result in increased amounts of intertidal zoobenthos in areas with predominantly high tidal flats, but in declines in lower areas. However, such changes will occur only if sea-level rise proceeds too fast to be compensated by extra sedimentation. Bottom subsidence as a consequence of gas extraction is expected to be too small to cause any measurable change in the benthic fauna.     

2015年5月黄海及东海北部大型水母分布及生物量估算

2015年5月搭载“北斗”渔业调查船、使用渔拖网的采样方式,在整个黄海及东海北部进行系统的走航式大面调查,记录了30°N—39°N海区内的大型水母种类组成、伞径大小及生物量分布,估算和比较了大型水母与其他渔业生物的生物量。结果表明,5月整个调查区,大型水母的总生物量估算值5.9万t,绝大部分由黄海中部的多管水母和洋须水母生物量贡献所致。出现的大型水母种类伞径分布呈单峰型。不同种类的水母分布具有明显地理区域和水文偏好性。其中,洋须水母主要分布于黄海中、北部50m水深以深水域,多管水母主要分布于黄海中部50m水深以浅的西侧以及整个东海北部;沙海蜇多为幼体,分布于黄、东海交汇区31°N—33°N间;霞水母较为集中出现于31°N以南、123°N以西近海。各水母种类的高密区的底层水温按洋须水母、沙海蜇、四叶小舌水母、霞水母呈升高趋势。东海多管水母分布区的底层水温与沙海蜇相近;黄海多管水母分布区的底层水温较洋须水母略高。沙海蜇和四叶小舌水母较其他水母的适温范围宽。霞水母和洋须水母处于相对高盐区域。     

Trend analysis of relative sea level rise or fall of the tide gauge stations in the Pacific

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东海和凯尔特海潮流沙脊的对比研究

东海潮流沙脊与凯尔特海沙脊均为开阔陆架上的大型深水沙脊，它们都形成在冰后期海面上升时期。目前仍然经受现代潮流和风暴浪的作用，具有一定的活动性，处于活动沙脊和衰亡沙脊之间的发育过程，属于准活动沙脊。与东海比较，凯尔特海的动力作用更强。东海沙脊横剖面大多呈向西南方向倾斜的前积层理，偶见波浪侵蚀面，反映以潮流作用为主形成的沙脊内部结构的特点；凯尔特海沙脊剖面呈现复杂的交错层理，内部有较多的波浪侵蚀面，这是潮流和波浪共同作用形成的沙脊内部结构的特点。     

One-Dimensional Hydraulic Analysis of the Effect of Sea Level Rise on Salinity Intrusion in the Sebou Estuary,Morocco

Global climate change has resulted in a gradual sea-level rise. Sea-level rise can cause saline water to migrate upstream in estuaries and rivers, thereby threatening freshwater habitat and drinking water supplies. On the other hand, sea-level rise, resulting from thermal expansion of ocean waters and increased melting of glaciers and ice caps, is one of the most apparent and widespread consequences of climate change. This phenomenon has been taken into account in all the Assessment Reports published by the Intergovernmental Panel on Climate Change (IPCC). In this paper, salinity intrusion and intrusion length due to possible sea-level rise in the Sebou estuary (Morocco) was investigated. A one-dimensional hydrodynamic-salinity transport model was used for the simulation of the salinity intrusion and associated water quality, with observed field data being used for model calibration and validation. Additionally, the model validation process showed that the model results fit the observed data fairly well. A coupled gas-cycle/climate model was used to generate the climate change scenarios in the studied area that showed sea-level rises varying from 0.3 to 0.9 m for 2100. The models were then combined to assess the impact of future sea-level rise on the salinity distribution and intrusion length in the Sebou estuary. The response of salt intrusion length to changes in important dimensional parameters are presented, showing that the salinity intrusion length is inversely correlated with the river discharge, i.e., a high river discharge results in a reduced salt intrusion and vice versa, and directly with the sea-level rise. Additionally, the magnitude and frequency of the salinity standard violations at the two pump stations were predicted for 2100, showing that the salinity violations under climate change effects can increase to ～45–48% of the times at these locations. Finally, the main objective of this simulation method is to accelerate and facilitate of systems' behavior learning in the current and future situation.     

长江三峡建坝前后流量和海平面对感潮河段潮位的影响差异

三峡大坝运行和海平面上升对河口水文动力变化的影响广受国内外关注。本文选取长江感潮河段沿程6个站（芜湖、马鞍山、南京、镇江、江阴和天生港） 1963-1985年（其中1970年和1971年数据缺失）和2003-2013年（其中2008年和2012年数据缺失）共30个年份的1月和7月的月均高潮位资料,以及相应月份上游大通站的流量（1950-2013年）、长江河口吴淞站潮位资料,通过肯德尔趋势分析、回归分析和偏相关分析等方法研究长江感潮河段潮位变化规律和影响因素。结果表明,三峡建坝后：（1）枯季流量和海平面的增加,导致上下段（以江阴为界）的潮位分别上升了0.33 m和0.20 m;洪季流量减少和海平面增加,导致上段潮位减小0.19 m、下段潮位增加0.04 m。（2）感潮河段洪季海平面与潮位回归方程的斜率均增加,表现为建坝后洪季洪涝灾害增加。（3）上下段流量和海平面对潮位贡献率的显著变化是导致上下段潮位呈现不同演变趋势的主要原因。     

渤、黄、东海潮汐、潮流的数值模拟与研究

基于FVCOM海洋数值模式,采用高分辨率的三角形网格,对渤、黄、东海的潮汐、潮流进行数值模拟,并通过比较120个沿岸验潮站和14个潮流观测站的实测与模拟结果进行模型验证,两者符合较好。根据模拟结果,给出了四个主要分潮的潮汐同潮图和5m层潮流最大流速及最大潮流同潮时分布。渤、黄、东海共有5个半日分潮和3个全日分潮的独立旋转潮波系统,且都呈逆时针方向旋转;半日潮流和全日潮流各有12个圆流点;在冲绳岛和奄美岛两侧的4个半日潮流圆流点分别呈对称分布,其中有3个为本文首次给出;在日本九州岛西侧还新给出2个全日潮流圆流点。有关它们的存在性需要实测资料的进一步检验。     

东海陆架冰后期潮流沙脊地貌与内部结构特征

东海陆架以宽平的地形、充分的陆源沉积物供应、快速沉降和强动力场为特征，中外陆架发育大规模潮流沙脊地貌。潮流沙脊走向大致为NW—SE向分布，与区域潮流主方向一致或成较小交角。东海陆架冰后期潮流沙脊以不对称横剖面为特征，陡坡倾向SW。沙脊内部发育典型的高角度前积斜层理，倾向与沙脊横剖面陡坡方向一致。这些斜层理可以划分为高达4组不同特征的组合，分别代表潮流沙脊发育的不同阶段，对应于冰后期海平面上升的不同时期。东海陆架潮流沙脊主体形成于冰后期海侵阶段，目前仍然受到陆架潮流场的影响，沙脊顶部为再沉积活动层。     

Sea level variations in the regional seas around Taiwan

The patterns and trends of sea level rise in the regional seas around Taiwan have been investigated through the analyses of long-term tide-gauge and satellite altimetry data. Series of tide-gauge data extending over 50 years reveal decadal and interannual variations and spatially-inhomogeneous patterns of generally rising sea level. The East Asia tide-gauge stations around Taiwan show an average trend of +2.4 mm/yr from 1961–2003, which is larger than the reported global rate of +1.8 mm/yr for the same period. These stations also show significantly larger sea level rise rates (+5.7 mm/yr) than global values (+3.1 mm/yr) during the period from 1993–2003. Consistent with the coastal tide-gauge records, satellite altimetry data show similar increasing rates (+5.3 mm/yr) around Taiwan during the same period. Comparisons with temperature anomalies in the upper ocean suggest that thermal expansion and heat advection in the upper layer contribute significantly to the long-term sea level variations in this area with correlations >0.9 for observations after 1992. Thermosteric sea level variations may also explain the interannual and decadal variations of the observed sea level rises around Taiwan. Our analysis also indicates that the altimetry data are only part of a long-term, larger-scale signal. Finally, we have found that a non-linear smoother, LOESS, is more suitable for extracting long-term trends in sea level than the traditional linear regression approach.     

The Cosmonaut Sea Wedge

A set of multi-channel seismic profiles (∼15,000 km) is used to study the depositional evolution of the Cosmonaut Sea margin of East Antarctica. We recognize a regional sediment wedge, below the upper parts of the continental rise, herein termed the Cosmonaut Sea Wedge. The wedge is situated stratigraphically below the inferred glaciomarine section and extends for at least 1,200 km along the continental margin with a width that ranges from 80 to about 250 km. The morphology of the wedge and its associated depositional features indicate a complex depositional history, where the deep marine depositional sites were influenced by both downslope and alongslope processes. This interaction resulted in the formation of several proximal depocentres, which at their distal northern end are flanked by elongated mounded drifts and contourite sheets. The internal stratification of the mounded drift deposits indicates that westward flowing bottom currents reworked the marginal deposits. The action of these currents together with sea-level changes is considered to have controlled the growth of the wedge. We interpret the Cosmonaut Sea Wedge as a composite feature comprising several bottom current reworked fan systems. The wide spectrum of depositional geometries in the stratigraphic column reflects dramatic variations in sediment supply from the continental margin as well as varying interaction between downslope and alongslope processes.     

Tidal oscillations in the Caspian Sea

Long-term hourly data from 12 tide gauge stations were used to examine the character of tidal oscillations in the Caspian Sea. Diurnal and semidiurnal tidal peaks are well-defined in sea level spectra in the Middle and South Caspian basins. High-resolution spectral analysis revealed that the diurnal sea level oscillations in the Middle Caspian Basin have a gravitational origin, while those in the South Caspian Basin are mainly caused by radiational effects: the amplitude of diurnal radiational harmonic S₁ is much higher than those of gravitational harmonics О₁, P₁, and K₁. In the North Caspian Basin, there are no gravitational tides and only weak radiational tides are observed. A semidiurnal type of tide is predominant in the Middle and South Caspian basins. Harmonic analysis of the tides for individual annual series with subsequent vector averaging over the entire observational period was applied to estimate the mean amplitudes and phases of major tidal constituents. The amplitude of the M₂ harmonic reaches 5.4 cm in the South Caspian Basin (at Aladga). A maximum tidal range of 21 cm was found at the Aladga station in the southeastern part of the Caspian Sea, whereas the tidal range in the western part of the South Caspian Basin varies from 5 to 10 cm.     

Tidal transport through the Tsugaru Strait — part I: Characteristics of the major tidal flow and its residual current

The potential role of the tide-induced time-mean flow (the tidal residual current) in determining transport through the Tsugaru Strait (located between the East/Japan Sea and the North Pacific) is investigated using a high-resolution numerical barotropic model. The calculated K₁, O₁, M₂, and S₂ tidal fields agree well with available observational records derived from both tide gauge and current meter measurements in the strait and the adjacent seas. The tidal residual current speed reaches 0.3 ms⁻¹ in two narrow “neck” areas where topographic sills are located. This result suggests that tides should be taken into account in estimating the long-term water mass and nutrient transport through narrow regions between the East/Japan Sea and the North Pacific. An interesting aspect of the tidal residual current field is the prediction of several active eddy zones in which sequences of eddy triplets develop in the vicinity of capes. Our vorticity analysis reveals that the interplay of topographic effects arising from both the headland and the sill around capes plays a critical role in the formation of these triple eddy patterns.     

强人类活动驱动下珠江磨刀门河口径潮动力的季节性异变特征

人类活动对河口环境影响巨大,揭示在强人类活动驱动下河口径潮动力非线性相互作用的异变特征,有利于了解人类活动影响河口动力地貌的机制,对河口区水利工程建设及环境保护等具有重要指导意义。基于1960—2016年珠江磨刀门河口沿程潮位站(甘竹、竹银、灯笼山、三灶)的逐月高、低潮位数据及马口水文站的月均流量数据,统计分析了磨刀门河口在强人类活动驱动下月均水位、潮波振幅及其空间梯度(即月均水位坡度和潮波振幅衰减率)的季节性异变特征。结果表明,1990年和2000年为磨刀门河口径潮动力的异变年份, 1990年前为自然演变阶段, 2000年后为恢复调整阶段,1990—2000年为过渡阶段;高强度采砂导致的河床下切使磨刀门河口月均水位及月均水位坡度显著减小,夏季减小幅度最为明显,沿程平均分别减小0.53m和8.93×10~(-6);月均水位坡度减小导致潮波衰减效应减弱,进而使沿程潮波振幅增大,多年平均增大0.071m;磨刀门河口径潮动力相互作用具有明显的季节性差异,夏季月均水位坡度随流量增大在上游抬升明显,冬季月均水位坡度在上游显著减小,但在下游略有抬升;随着流量的增大潮波振幅的衰减作用增强,但当流量超过阈值20000m~3/s时,月均水位坡度引起的底床摩擦增大效应不足以抵消横截面积辐散效应,潮波衰减效应略有减弱。