湛江湾三维温盐特征季节变化观测分析

利用2017年1?12月的现场观测数据,分析了湛江湾温盐的三维空间结构及季节变化特征。结果表明:(1) 2017年湛江湾各站位年平均温度为23～27℃、盐度为19～27、位势密度为11～17 kg/m3、浮性频率(N2)为7×10?5～5×10?3 s?2。浮性频率的垂向结构及水平分布与温度分布类似,而位势密度则与盐度的变化趋势几乎一致;(2)温度季节变化明显,夏季最高,秋季次之,冬季最低,冬夏温差最大达15℃,而盐度季节变化则不大。相较于季节引起的变化,涨落潮对温度以及盐度影响较小。温度跃层夏季最强,10 m处温度最大梯度可达到0.7℃/m,春秋季温跃层抬升至5 m附近,冬季水体上下混合均匀。夏季和秋季存在明显的盐跃层,盐度梯度最大可达到1.1 m?1。跃层上下温盐的季节变化规律一致;(3)水平分布上,从湾顶区、湾颈区、大堤区、浅滩区到湾口区,温度递减,盐度递增,湾顶区和湾口区平均温度差为2.3℃,盐度差为2.7。温盐图分析显示,不同季节水体呈现为不同的温盐条带,湾口区基本为低温、高盐水体,而湾顶区基本为高温、低盐水体,其他区域水体介于上述两者之间。     

黄海中部太平洋磷虾的大小组成和丰度分布的季节变化及其与环境因子的关系

The seasonal size structure and spatial abundance distributions of Euphausia pacifica populations were investigated in the central part of southern Yellow Sea from August 2009 to May 2010.The abundance and biomass of E.pacifica were higher in spring and summer,and lower in autumn and winter.The mean abundance and biomass(calculated by carbon)were 74.94 ind./m~3 and 8.23 mg/m~3,respectively.Females with total length(TL)ranging between 10 and 19 mm in summer had a substantial contribution to the population biomass,whereas larvae of TL of 3–7 mm in spring were the main contributor to the population abundance.The sex ratio(female:male)showed a female bias in four seasons.Its value peaked in summer,and then decreased in autumn,spring,and winter successively.Cohort analysis revealed that the length-frequency distribution of E.pacifica could be characterized as one group with large animals(mean TL12 mm)accompanied by one or two subgroups of small individuals(mean TL7 mm).Regarding the spatial distribution,juveniles and adults of E.pacifica tend to concentrate in relatively deep water with low temperature(～11℃)and high salinity(32),whereas its larvae showed more abundance in inshore water with rich chlorophyll a,low salinity(32),and warm temperature(11℃),especially in summer and autumn.Associations changed seasonally between stage-specific abundance and environmental factors.     

东海西部陆架海域水团的季节特征分析

On the basis of the CTD data and the modeling results in the winter and summer of 2009, the seasonal characteristics of the water masses in the western East China Sea shelf area were analyzed using a cluster analysis method. The results show that the distributions and temperature-salinity characteristics of the water masses in the study area are of distinct seasonal difference. In the western East China Sea shelf area, there are three water masses during winter, i.e., continental coastal water（CCW）, Taiwan Warm Current surface water（TWCSW） and Yellow Sea mixing water（YSMW）, but four ones during summer, i.e., the CCW, the TWCSW, Taiwan Warm Current deep water（TWCDW） and the YSMW. Of all, the CCW, the TWCSW and the TWCDW are all dominant water masses. The CCW, primarily characterized by a low salinity, has lower temperature, higher salinity and smaller spatial extent in winter than in summer. The TWCSW is warmer, fresher and smaller in summer than in winter, and it originates mostly from the Kuroshio surface water（KSW） northeast of Taiwan, China and less from the Taiwan Strait water during winter, but it consists of the strait water and the KSW during summer. The TWCDW is characterized by a low temperature and a high salinity, and originates completely in the Kuroshio subsurface water northeast of Taiwan.     

Seasonal variations of water temperature and salinity in Osaka Bay

The characteristics of seasonal variations of water temperature, salinity and density in the upper, middle and lower layers in Osaka Bay are described. Osaka Bay is considered to be an estuary, because the weak mixed state appears in spring and summer and the moderate mixed state in autumn and winter. Osaka Bay is divided into three areas, the eastern shallow area that has a large amplitude of seasonal variation of water temperature and low average salinity, the southwestern deep area which has small amplitude of seasonal variation of water temperature and high average salinity, and the northwestern deep area, which has small amplitude of seasonal variation of water temperature and low average salinity.     

南黄海夏季温盐年际变化时空模态与气候响应

根据南黄海断面1977—2016年历年8月标准层温度、盐度与气候要素观测资料,采用时空分析等方法,分析了南黄海断面夏季温度、盐度年际时空变化与气候响应。断面温度主要有4种时空模态,夏季风生环流、冷水团强度、面积与断面冬季温度模态是主要温度模态年际变化的主要影响因素;夏季风生流场形态、春季PDO指数与断面冬季温度模态是次要温度模态年际变化的主要影响因素;温度模态时间分量均为准平衡态长期变化。断面盐度主要有4种时空模态,夏季苏北沿海低盐度水体、南黄海中部高盐度水体与夏季黄海风生流输送作用是盐度主要模态年际变化的主要影响因素;夏季南黄海降水量减少与风生流输送减弱是盐度次要模态年际变化的主要影响因素。盐度主要模态时间分量为准平衡态长期变化,次要模态时间分量存在显著线性低盐趋势变化。断面夏季温盐多年平均分布主要受到夏季多年平均风生环流影响。断面核心冷水团月平均温度为准平衡态长期变化;面积存在显著线性减小趋势,黄海风生流场季节与年际变化是南黄海核心冷水团年际变化主要影响因素,春季PDO指数对冷水团面积年际变化有显著非线性影响。断面冷水团、核心冷水团月平均盐度为显著线性低盐趋势周期年际变化。由于黄海温盐长期线性趋势变化,与30多年前状况相比,目前黄海温盐场季节循环时空变化形态可能已经发生显著改变。     

基于PHC3.0数据集的北冰洋水团分析

基于PHC3.0极地科学中心水文气候数据集(简称PHC3.0数据集)的温度和盐度资料,使用聚类分析和Bayes判别分析的方法,对北纬70°以北海域的水团结构进行了分析,在北冰洋区域划分出4个水团:北冰洋表层水(ASW)、大西洋中层水(AIW)、太平洋水(PW)和北冰洋深层水(ADW)。北冰洋表层水(ASW)遍布于欧亚海盆和加拿大海盆,以低温低盐为特征。大西洋中层水(AIW)位于约200～900m深度,在北冰洋环极边界流的作用下,其影响可达到加拿大海盆。太平洋水(PW)受经白令海峡进入北冰洋的海水影响,相对高温低盐,夏季时影响显著。北冰洋深层水(ADW)在海盆中相当均匀,几乎没有季节变化,盐度约在34.95psu,温度在加拿大海盆约为-0.3℃,欧亚海盆约为-0.7℃。     

山东半岛东北部海域悬浮体季节分布及控制因素

基于2018年山东半岛东北部海域冬、夏两季悬浮体浓度、浊度及水温和盐度调查资料,分析了研究区水体悬浮体浓度的季节性变化,探讨了其控制因素。结果表明:夏季浊度在0.2~37.8FTU之间变化,冬季浊度在1.5~100.1FTU之间变化,均表现为底高表低、东高西低的特征。夏季水温分层明显,表现为表层高、底层低的特征,盐度整体无明显变化;冬季温盐垂向上混合均匀,平面上表现为近岸低温低盐水体向远岸高温高盐水体的过渡。悬浮体浓度分布受潮流、波浪、温跃层和温盐锋面等因素影响。夏季,悬浮体垂向上受到温跃层影响,底层悬浮体难以向表层输运;平面上潮混合和波浪差异性作用阻碍了悬浮体的水平输运。冬季,强风浪促使悬浮体垂向混合剧烈,表层悬浮体浓度明显较夏季变高;平面上沿岸流和黄海暖流形成的温、盐锋面阻碍了水团间悬浮体的输运。     

Transformation of black-sea waters in the Sea of Marmara

The analysis is performed on the basis of comparison of the hydrological characteristics of prestrait regions of the Sea of Marmara. It is shown that, in summer, the Black-Sea waters are weakly mixed with the Mediterranean waters and the levels of salinity in the prestrait regions differ by 0.6–0.9‰. In winter, the indicated difference increases and the level of salinity near the entrance of Dardanelles reaches 29‰ and exceeds the level observed near the entrance of Bosporus by 5.5‰. In the analyzed regions, we observe local temperature maxima and minima near the interface of two water masses. This is explained by the presence of strong seasonal variations of temperature for the Black-Sea waters and their absence for the Mediterranean waters. The physical mechanisms responsible for the seasonal variations of the intensity of transformations of the Black-Sea waters are discussed. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 2, pp. 49–55, March–April, 2007.     

闽江冲淡水扩展范围的季节变化特征

利用2006～2007年春、夏、冬季3个航次的CTD资料分析闽江冲淡水扩展范围季节变化特征.通过分析闽江口及邻近海域温度、盐度的平面、垂直分布特征,结果表明:闽江冲淡水的扩展范围具有明显的季节变化.春季由于闽江口附近受到闽浙沿岸流的影响,冲淡水的扩展范围难以确定,但从盐度分布情况不难看到闽江口表层被盐度低于25的具有明显冲淡水特征的水体覆盖.夏季闽江口被温度高于27℃、盐度低于25的冲淡水覆盖,冲淡水前沿向东北扩展至罗源湾、三沙湾.冬季闽江径流减弱,闽江口主要受到闽浙沿岸水的影响,基本看不到闽江冲淡水的痕迹.春季、夏季闽江冲淡水明显的影响闽江口时,闽江口附近海域被25盐度等值线包围,25盐度等值线可作为闽江口明显受冲淡水影响的指征.     

北黄海及渤海变性水团的初步分析

根据1978—1980年渤海及北黄海70个测站的表、底层温、盐资料,用预先给定控制临界值的聚类方法,在该海域划分出5个水团。分析结果表明。1.渤黄海暧水团在冬季为高盐特征,夏季为中盐性质;其分布范围在冬—春季较小而夏—秋季较大。2.渤海水团为中温中盐性质:其温、盐度变化较小而冬—春季范围较大。3.黄海冷水团是一个高盐水团,它在5个水团中保守性最强,而从5月至8月范围较大。4.渤海沿岸水是一个不稳定的水团,其盐度较低,温度变化较小,春季和秋季范围较大而夏季和冬季较小。5.江河冲淡水是温度变化较大的低盐水,其范围夏季大而冬季小。水团的分布,在地理位置上是从该海区之东向西,一层套一层,而各水团在不同季节有自己的模式。此外,本文还探讨了水团消长变化和渔场的关系。     

东海G断面平均温、盐度变化与厄尔尼诺关系的初步分析

本文试图利用位于东海黑潮区G断面温、盐度的多年观测资料,对该断面平均温、盐度变化与厄尔尼诺的关系进行了分析,以期有助于研究黑潮对我国东海及邻近海域环流和沿海气候的影响。 Ⅰ.资料来源及统计方法 由于采用的划分标准和指数不同,因而对     

关于黑潮延伸体海域水体的三维热结构时-空变化特征研究

基于西北太平洋Argo数据资料,利用参数化方法,从Argo温盐剖面数据中提取出一系列特征动力参数,定量分析黑潮延伸体海域水体的三维热结构的时-空变化特征、季节变化特征及其与地形和环流的关系。结果表明:黑潮延伸体海域水体的海表面温度存在着明显的冬春弱,夏秋强的季节变化特征,冬季平均海表面温度为15℃,夏季则达到了27℃;混合层深度在春季和夏季都较深,在180 m左右,秋冬较浅,在17 m左右,在水平方向上混合层深度有较强的梯度;温跃层春、夏、秋、冬4季的平均温度表现出明显的南北差异,夏季南部海域平均温度为14℃左右,北部海域较低为5℃左右;季节性温跃层深度大约在100 m左右;黑潮延伸体海域水体的温跃层底部最大深度在800 m左右;黑潮延伸体主体海域中心位置冬天在36°N左右,夏天大约移到34°N。     

Seasonal distribution of Calanus sinicus (Copepoda, Crustacea) in the East China Sea

On the basis of the four-season investigation in 23°30′~33°N and 118°30′~128°E of the East China Sea from 1997 to 2000, the seasonal distribution of Calanus sinicus was studied with aggregation intensity, regression contribution and other statistical methods. It was inferred that C. sinicus’s predominance presented from winter to summer, especially in spring and summer, because its dominance amounted to 0.62 and 0.29 respectively. The percent of its abundance in copepod abundance was 76.71% in summer, greater than 66.60% in spring, greater than 19.02% in winter, greater than 4.02% in autumn. The occurrence frequency in winter and spring was 83.08% and 93.89%, higher than that in summer and autumn, 76.71% and 73.87%. Compared with other dominant species of copepods, C. sinicus’s contribution to the copepod abundance was obviously greater than that of the other species in winter, summer and spring, but smaller in autumn. C. sinicus tended to have an aggregated distribution. The clumping index peaked in summer (50.19), followed in spring (19.60), declined in autumn (13.18) and was the lowest in winter (3.04). The abundance changed in different seasons and areas, relating to temperature but not salinity in spring and autumn, to salinity but not temperature in summer; to neither temperature nor salinity in winter. In spring and summer, its high abundance area was often located in the mixed water mass formed by the Taiwan Warm Current, the Huanghai Sea Cold Water Mass, the coastal water masses and the Changjiang Dilute Water. In spring and autumn, its abundance was affected by the warm current, as well as the runoff from continental rivers affected it in summer. It can be inferred that C. sinicus was adapted to wide salinity and temperature, as a euryhalinous and eurythermous species in the East China Sea.     

北黄海冷水团季节变化特征分析

利用2006—2007年春、夏、秋、冬4个航次的CTD数据,对北黄海冷水团的季节变化及其消长过程进行了分析.结果显示:春季,冷水团特征开始出现,6℃冷水占据了调查区域的1/3,冷水团中心的盐度值大于32 psu.成山头以东的高盐水舌主轴从冬季的124°E西移至123.3°E处;夏季,北黄海冷水团特征最为明显,核心温度约6℃,盐度高于32 psu,盘踞在50 m等深线以深的深槽中,温、盐呈现明显的双峰结构.与前人的结果相比,本文低温中心的位置偏东;秋季,北黄海冷水团强度减弱,但仍存在2个低温中心,并且高盐中心位于38.5°N,122.5°E附近;在垂直方向上,冷水团与上层水之间以温跃层为分界:温跃层春季时形成,位于20～30m;夏季达到最强,跃层在10～20m;秋季减弱,跃层深度降至30～40m;至冬季温跃层完全消失.     

Seasonal and interannual evolution of the mixed layer in the Antarctic Zone south of Tasmania

Seasonal and interannual variations of the mixed layer properties in the Antarctic Zone (AZ) south of Tasmania are described using 7 WOCE/SR3 CTD sections and 8 years of summertime SURVOSTRAL XBT and thermosalinograph measurements between Tasmania and Antarctica. The AZ, which extends from the Polar Front (PF) to the Southern Antarctic Circumpolar Current Front (SACCF), is characterized by a 150 m deep layer of cold Winter Water (WW) overlayed in summer by warmer, fresher water mass known as Antarctic Surface Water (AASW). South of Tasmania, two branches of the PF divide the AZ into northern and southern zones with distinct water properties and variability. In the northern AZ (between the northern and southern branches of the PF), the mixed layer depth (MLD) is fairly constant in latitude, being 150 m deep in winter and around 40–60 m in summer. In the southern AZ, the winter MLD decreases from 150 m at the S-PF to 80 m at the SACCF and from 60 to 35 m in summer. Shallower mixed layers in the AZ-S are due to the decrease in the wind speed and stronger upwelling near the Antarctic Divergence. The WW MLD oscillates by ±15 m around its mean value and modest interannual changes are driven by winter wind stress anomalies.The mixed layer is on annual average 1.7 °C warmer, 0.06 fresher and 0.2 kg m⁻³ lighter in the northern AZ than in the southern AZ. The Levitus (1998) climatology is in agreement with the observed mean summer mixed layer temperature and salinity along the SURVOSTRAL line but underestimates the MLD by 10–20 m. The winter MLD in the climatology is also closed to that observed, but is 0.15 saltier than the observations along the AZ-N of the SR3 line. MLD, temperature and density show a strong seasonal cycle through the AZ while the mixed layer salinity is nearly constant throughout the year. During winter, the AZ MLD is associated with a halocline while during summer it coincides with a thermocline.Interannual variability of the AZ summer mixed layer is partly influenced by large scale processes such as the circumpolar wave which produces a warm anomaly during the summer 1996–1997, and partly by local mechanisms such as the retroflection of the S-PF which introduces cold water across the AZ-N.     

The hydrography of the mid-latitude Northeast Atlantic Ocean: II: The intermediate water masses

The intermediate water masses in the eastern Atlantic Ocean between 31°N and 53°N were studied by analysis of the distributions of potential temperature, salinity, dissolved nutrients and oxygen. Sub-surface salinity minima are encountered everywhere in the area. At the northern and southern boundary they are connected with the presence of Sub-Arctic Intermediate Water and Antarctic Intermediate Water, respectively, but towards the European ocean margin the sub-surface salinity minima shift to shallower density levels. The sub-surface salinity minima observed west of the Iberian Peninsula represent a water mass formed by winter convection in the Porcupine Sea Bight and the northern Bay of Biscay. These minima gain salt by diapycnal mixing with the underlying Mediterranean Sea Outflow water and with the overlying permanent thermocline. The core of Antarctic Intermediate Water appears to contribute to the formation of Mediterranean Sea Outflow Water since it becomes entrained into the overflow near Gibraltar. This entrainment gives rise to an enhanced concentration of the nutrients in the Mediterranean water in the North Atlantic. The deep salinity minimum, due to the presence of Labrador Sea Water, is restricted mainly to the Porcupine Abyssal Plain. In the Bay of Biscay this water type is strongly modified by enhanced diapycnal mixing near the continental slope. At all intermediate levels the continental slope in the Bay of Biscay seems to be a focal point for water mass modification by diapycnal mixing. Below the core of the Mediterranean Sea Outflow Water the Labrador Sea Water is also strongly modified. Its salinity is strongly enhanced by diapycnal mixing with the overlying core of Mediterranean Sea Outflow Water. An analysis of the oxygen and nutrient data indicates that the large spatial concentration differences at the level of the Labrador Sea Water are caused mainly by ageing of the water. The youngest water is observed at 52°N, and, especially in the Bay of Biscay and off south-west Portugal, the water at levels of about 1700 dbar are strongly enriched in nutrients and depleted in oxygen.     

Distribution pattern of pelagic amphipods and its affecting facors in the East China Sea

1 IntroductionAmphipoda, an order of marine pelagic shell-fish, belongs to class Crustacea, subclass Malacost-raca (Chen and Shi,2002). Species of this ordercan be found all over the world, especially in tropi-cal and subtropical oceans. As fish diets, th…     

菲律宾海盆深层温盐结构与环流变化特征研究

基于ECCO2 (Estimating the Circulation and Climate of the Ocean)、 GLORYS12V1 (Global Ocean Reanalysis and Simulations)、ORA-S5 (Ocean ReAnalysis)三种海洋再分析数据,对比研究了菲律宾海盆深层温盐及环流的季节和年际变化特征。结果表明:三种数据显示的海盆深层温盐季节变化特征基本一致,在3 000～4 000 m水深区域,海水呈春夏两季高温低盐而秋冬季低温高盐特性,4 000 m以下海水温盐季节变化很小;沿西边界,温度与内部有明显差异且季节变化幅度相对较大。沿西边界的输运季节变化特征表现为10月至次年4月输运向南,5—9月输运向北,并且在8月份达最大值;表明存在沿西边界的流动,即菲律宾海盆与南端西卡罗林海盆(West Caroline Basin)之间存在季节性水体交换。海盆深层海水温盐年际变化也十分显著,但不同数据显示的变化特征存在较大差异。EOF和相关分析显示,三种再分析数据的深层位温与ENSO均存在一定相关性,ECCO2的深层位温变化与ENSO的相关性最强。由于长期观测数据较少,再分析数据的结果难以验证,因此目前对年际变化特征的研究仍具有很大的不确定性。     

舟山渔场及其邻近海域水团的季节特征

根据2001年夏季和2002年冬季两次现场调查所收集的CTD和营养盐资料,利用模糊聚类分析法,对舟山渔场及其邻近海域水团的季节特征进行了分析.结果表明,舟山渔场及其邻近海域水团的配置、分布范围、温盐特性和营养盐含量都有明显的季节特征.其中,冬季在全海域共有3个水团(江浙沿岸水、台湾暖流表层水和黄海混合水),而夏季则存在4个水团(江浙沿岸水、台湾暖流表层水、台湾暖流深层水和黄海混合水);冬季,江浙沿岸水的分布范围较小,温度偏低,盐度略高,营养盐偏高,而夏季,其分布范围较大,温度偏高,盐度偏低,营养盐偏低;冬季,台湾暖流表层水北伸最强,厚度最厚,温度最低,盐度最高,硅酸盐和硝酸盐偏高,而夏季,则北伸最弱,厚度最薄,温度最高,盐度最低,硅酸盐和硝酸盐偏低;台湾暖流深层水是一个季节性水团,它含有较丰富的营养盐;黄海混合水的分布范围和营养盐含量也都呈现出明显的季节特征.     

Effect of winter meteorological conditions on the formation of the cold bottom water in the eastern Bering Sea shelf

The cold bottom water, formed in the previous winter on the eastern Bering Sea shelf, remains throughout the summer. in order to examine the mechanism for the formation of the cold bottom water, we used minimum water temperature in the cold bottom water observed over the eastern Bering Sea shelf for 30 years. The interannual variation in the minimum water temperature of the cold bottom water was closely related to that of mean air temperature during cooling period at St. Paul Island. The air temperature in previous winter primarily affects the cold bottom water. We estimated decrement of the water temperature due to ice melting with simple box model. It was found with the box model that decreasing of the water temperature and lowering of the salinity depend on ice melting. To investigate the cause of interannual variation in air temperature in winter, we applied EOF analysis to the 500 hPa height. The Pacific/North American pattern (PNA) was related to mean air temperature at St. Paul Island in cooling season and the cold bottom water temperature. These results suggest the connection between ENSO events and warming or cooling in the Bering Sea shelf in winter.