首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 187 毫秒
1.
1978年12月18日至1979年7月21日“向阳红”09调查船在执行由联合国组织的首次全球大气考察过程中,同时进行了地质及其他多学科的考察工作。本次考察海区限于170°—173°20′E、4°—10°S(一区)和160。—165E、4°S—5°N(二区)两个海区(图1)。  相似文献   

2.
利用1982年1月至2001年12月逐日的Re_NCEP南海海表面潜热通量资料,分析了南海夏季西南季风爆发早年和晚年潜热通量在南海的时空分布特征;并通过相关对比诊断分析了潜热通量对西南季风爆发及强度的影响,初步给出了其动力学机理。结果表明,季风爆发早、晚年的前一年冬季至初春(12~3月),南海南部(5°~13°N,100°~120°E)和北部(13°~22°N,105°~120°E)的潜热通量距平符号相反,呈现反位相,季风爆发早(晚)年,前一年冬季至次年初春,南海北部的潜热通量为正(负)距平,南海南部则为负(正)距平;在季风爆发的早年和晚年,南海潜热通量表现出明显的差异,春、夏、秋季南海潜热通量正距平持续时间短(长),季风强度偏弱(强)。南海北部的潜热通量和南海北部季风强度隔季正相关。当潜热通量为正(负)距平时,同期和滞后1~3个月的海温均为负(正)异常,加大(减小)了春季南海和周围陆地陆暖海冷的海陆温差,有利于西南季风在南海北部的早(晚)爆发,西南风异常偏强(弱)。  相似文献   

3.
有关太平洋海洋环流,特别是对亚热带(又称副热带)、热带和赤道带环流的调查研究,近数十年来在国内、外海洋学界已蓬勃展开。其中,日本气象厅于1967年至今在137°E断面上每年进行1-2次定期海洋观测,并于1972-1979年、1987-1995年在155°E断面上每年夏季进行一次观测。根据上述经向断面观测资料,许多学者对137°E断面的海流结构,温、盐分布,水团及其变异,以及与ENSO现象的关系作了细致的分析研究(邹娥梅等,1993;顾玉荷,1996;Guan,1986;Masuzawa,1967);关于155°E断面的研究,则着重于太平洋赤道区域海流结构和它的变异及其与ENSO现象的关系等(顾玉荷,1990;Guan,1986)。本文拟根据155°E断面1972-1979年夏季(6-7月)日本气象厅的海洋水文气象观测资料(其中1974年无资料),分析研究该断面(北亚热带、热带和赤道带海域)的温、盐度分布特征和热、盐含量及其年际变异,并探讨其与ENSO现象之间的关系。 155°E断面北起30°N,南至11°S,自北向南横穿北亚热带、热带、赤道带和南半球热带。测站的密度以1975-1977年最密(设55个测站),1972年和1973年次之(分别设测站33个和40个),1978年和1979年测站稀疏,仅为15个和12个。采样深度间隔于30m以浅为10m,50-150m层间为25m,150-300m层间为50m,300-1000m层间为100m。图1为断面的位置和站位分布(5028站至5058站每相邻两站中间省略一站位)。 为了便于分析断面上各纬度带的水文特征及年际变异,将该断面自北向南划分为4个纬度带,即北亚热带(18°-30°N)、北半球热带(2°-18°N,以下简称北热带)、赤道带(2°N-2°S)和南半球热带(2°S以南,以下简称南热带)。其中北热带又划分为北赤道流区(8°-18°N)和北赤道逆流区(2°-8°N)。  相似文献   

4.
南海中部海域障碍层特征及其形成机制   总被引:2,自引:0,他引:2  
南海中部海域(10°~19°N,108°~122°E)存在显著的季节变化的障碍层.障碍层发生概率夏季最大(52.8%),秋季次之(41.0%),春季最小(10.5%).夏季(2000年8~9月)障碍层最显著,平均厚度约为14.2m;除114°E以东、吕宋岛以西海域为障碍层的多发区外,中南半岛东南海域(12°~14°N,110°~114°E)也存在显著的障碍层;春季(1998年4~6月)和秋季(1998年12月)障碍层平均厚度分别为6.8和11.2m,障碍层多位于114°E以东、吕宋岛以西海域.此外,吕宋岛以西海域(12°~16°N,116°~120°E)及中沙和西沙群岛附近(16°~18°N,110°~116°E)海域障碍层年发生几率超过20%,相对而言,其他海域障碍层年发生几率偏小.降水机制和层结机制分别是南海中部海域春、夏季和秋季障碍层形成的主要原因.其中,降水机制及东南向的Ekman平流较好的解释了春、夏季吕宋岛以西附近海域成为障碍层多发区的原因;此外,强降水是夏季中南半岛东南海域(12°~14°N,110°~114°E)障碍层产生的关键,反气旋涡(暖涡)有助于形成更强的障碍层,上升流对障碍层的影响有待进一步研究.  相似文献   

5.
浙江中南部外侧海区的虾类资源   总被引:4,自引:0,他引:4  
本文根据1986年8月至1987年11月浙江中南部海域(27°00′~29°30′N,125°00′E) 拖虾调查资料,分析了虾类资源的种类、组成,拖虾渔获量及主要种类的分布,提出进一步开发凹管鞭虾,假长缝拟对虾等新的虾类资源的建议,并讨论了合理利用的途径。  相似文献   

6.
根据中国第18次南极科学考察队2002年1~3月在南印度洋从中山站外普里兹湾到澳大利亚费里曼特尔断面的走航XBT/XCTD资料和CTD资料及1998年1月、1999年2月和2000年3月等其他航次的调查资料,分析了该航线上海洋锋的位置及其年际变化:(1)在75°~78°E南极陆坡锋的位置在645°~655°S;在84°~100°E范围极地锋在535°~543°S附近;在96°~103°E亚南极锋在46°S~470°S附近;在110°E附近亚热带锋在372~380°S之间;(2)在南极极锋区存在显著等温线、等盐线的上凸和下凹,不同年份发生位置有变化;(3)在亚南极锋北侧,等温线、等盐线呈垂直排列的状态,温度、盐度垂直方向上分布均匀一致;(4)与1979,1991和1992年该区域同期的资料相比,近4a观测到的极地锋显著偏南1个纬距以上.  相似文献   

7.
本文报道了1984年5月至1985年2月台湾海峡西部海域(22°19′—27°25′N,116°30′—121°E)活性硅酸盐、磷酸盐和三氮总含量的平面、断面、垂直分布和季节变化及其与沿岸径流和海峡中不同水系的消长、上升流、浮游植物的关系,以及各营养盐之间及其与盐度的相关性。  相似文献   

8.
通过对“向阳红16”号调查船1986年1月至3月在北太平洋中部热带海域(北纬7°~13°,西经178°~165°)进行综合科学考察时取得的深层水文观测资料的分析,指出该海域平均底层流是从西南流向东北。此结果与Knauss(1962)及Mantyla(1975)的分析结果相符。文中还初步分析了海底地形对深海水文要素分布的影响。  相似文献   

9.
水母类是海洋浮游生物重要类群之一,不仅种类多、数量大,而且分布广,不少种是世界性分布。有些种可作为一定海流或水团的指标。水母类除钵水母纲的少数种,如海蜇可供人们食用外,多数水母是幼鱼和甲壳类幼体的敌害,水母类触手的刺细胞或粘细胞含有毒素,对人类的健康有一定危害。 东海水母类研究工作先后有 Collingwood(1868)、 Light(1924)、林绍文(1937)、Sproston(1949)、丘书院(1954)、许振祖等(1962、1974)、高哲生等(1962)、洪惠馨(1964)、张金标等(1975)。以上大部分偏重于分类工作,研究材料大多采自沿海局部地区:因而不能概括东海水母类整个面貌。本文就东海水母类种类组成,分布概况及其与水文要素的关系作初步探讨。 本文所用材料是我所调査船于1959年1-12月在北纬28°以北、东经124°以西东海西部水域、1975年10月、1976年6-7月、8-9月三个航次在北纬26°31''-31°30′、东127°以西,水深30米以外的广阔东海大陆架区和1978年5月29日-7月3日在北纬26°31′-32°30′,东至东经129°,水深40米以外包括冲绳海槽在内的广大水域,进行浮游生物拖网采取的样品。 采集用大型浮游生物网(网长270厘米、网口面积0.5㎡、GG36筛绢)从底至表垂直拖网、标本用5%福尔马林海水固定,定量方法采用个体计数法,然后换算为单位体积水体中的个数(个/100m3)。  相似文献   

10.
利用1998~2003年6~8月的NCEP/NCAR再分析资料(1.0°×1.0°经纬度网格),以对流层中部500 hPa高度层为重点,利用北半球夏季(6~8月)低纬度(0°~30°N)太平洋地区(160°E-120°W)各物理量(水平速度u,v,P-坐标垂直速度ω等)计算了水平运动方程中各分量的大小,通过比较对热带大尺度运动方程进行了简化,并给出了相应的简化方程,认为纬向风在除了赤道这一奇异带以外都是满足地转平衡的,而经向风则在离开赤道30°以外达到地转.由于热带太平洋地区是台风的重要发源地之一,因此弄清此地区的大气运动基本平衡关系有助于台风形成机制的研究.  相似文献   

11.
孙军  刘东艳  张晨  钟华 《海洋学报》2003,25(5):103-112
对1998年9月和1999年4月在渤海(37°~41°N,117.5°~122.5°E)进行的两次生态系统综合外业调查,对蓬莱、长岛两地进行15个月的连续资料监测,对渤海调查区浮游植物粒级生物量的平面分布、垂直分布、昼夜变化和周年变化特征进行了研究.结果表明,秋季主要以小型浮游植物为主,然后依次为微型和微微型浮游植物;春季主要以微型浮游植物所占比重最高,其次为小型浮游植物,微微型浮游植物占比例最低.1998年秋季对断面1,2浮游植物粒级组分的垂直分布研究表明,在不同海区(调查区西部、南部、渤海中部和渤海海峡)的不同水层,浮游植物粒级生物量的分布有明显差异.潮汐对浮游植物粒级生物量的周日变化影响较大.蓬莱、长岛两地的连续调查资料表明,浮游植物各粒级组分除微微型浮游植物外1a有两个峰.网采浮游植物在4和7月有高峰,4月是主峰;小型网采浮游植物在6和11月有高峰,6月是主峰;微型浮游植物在4和11月有高峰,两峰值接近;微微型浮游植物在9月有高峰.调查区与其他海区浮游植物叶绿素a浓度粒级组分比较,表明小型浮游植物所占比重较大.  相似文献   

12.
This study examines the structural characteristics of the northern Gulf of California by processing and interpreting ca. 415 km of two-dimensional multi-channel seismic reflection lines (data property of Petróleos Mexicanos PEMEX) collected in the vicinity of the border between the Wagner and Consag basins. The two basins appear to be a link between the Delfín Superior Basin to the south, and the Cerro Prieto Basin to the north in the Mexicali-Imperial Valley along the Pacific–North America plate boundary. The seismic data are consistent with existing knowledge of four main structures (master faults) in the region, i.e., the Percebo, Santa María, Consag Sur, and Wagner Sur faults. The Wagner and Consag basins are delimited to the east by the Wagner Sur Fault, and to the west by the Consag Sur Fault. The Percebo Fault borders the western margin of the modern Wagner Basin depocenter, and is oriented N10°W, dipping (on average) ~40° to the northeast. The trace of the Santa María Fault located in the Wagner Basin strikes N19°W, dipping ~40° to the west. The Consag Sur Fault is oriented N14°W, and dips ~42° to the east over a distance of 21 km. To the east of the study area, the Wagner Sur Fault almost parallels the Consag Sur Fault over a distance of ~86 km, and is oriented N10°W with an average dip of 59° to the east. Moreover, the data provide new evidence that the Wagner Fault is discontinuous between the two basins, and that its structure is more complex than previously reported. A structural high separates the northern Consag Basin from the southern Wagner Basin, comprising several secondary faults oriented NE oblique to the main faults of N–S direction. These could represent a zone of accommodation, or transfer zone, where extension could be transferred from the Wagner to the Consag Basin, or vice versa. This area shows no acoustic basement and/or intrusive body, which is consistent with existing gravimetric and magnetic data for the region.  相似文献   

13.
1996年春季南黄海水文特征和水团分析   总被引:37,自引:8,他引:29  
利用中韩“黄海水循环动力学及物质输运”合作研究项目第一航次1996初春所获得的CTD资料描述了南黄海初春温、盐和密度的水平和垂直分布特征,分析了水团结构,并揭示了春季在34°~36°N,121°45'~124°E的南黄海西部水域的中层冷水现象。分析结果表明初春黄海暖流上表层开始向济州岛方向退缩,黄海底层冷水团首先在青岛外海形成。  相似文献   

14.
东海浮游翼足类(Pteropods)数量分布的研究   总被引:10,自引:1,他引:10  
徐兆礼 《海洋学报》2005,27(4):148-154
根据1997~2000年东海海域23°30'~33°00'N,118°30'~128°00'E的4个季节海洋调查资料,运用定量、定性方法,探讨了东海浮游翼足类总丰度的平面分布、季节变化及变化的动力学机制.结果表明,东海翼足类总丰度和出现频率有明显的季节变化,均为秋季最高,夏季次之,春季最低;总丰度在各个季节基本上呈东海南部高于北部、外海高于近海的分布趋势;春季的尖笔帽螺(Creseis acicula)、夏季的锥笔帽螺(Creseis virgula)、秋季的蝴蝶螺(Desmopterus papilio)和冬季的马蹄螔螺(Limacina trochiformis)是导致总丰度季节变化的最主要的种类;冬、春和夏3个季节丰度变化及4季总丰度的变化同表层或10m层水温有非常显著的线性相关关系,与底层温度及盐度的相关关系不显著.夏季翼足类高丰度区位于台湾暖流与黑潮暖流的分支处;从夏季到秋季,翼足类随着台湾暖流向北扩展,并在与长江冲淡水,闽浙沿岸水团,黄海水团等交汇处形成高丰度(大于500×10-2个/m3)和较高丰度(250×10-2~500×10-2个/m3)分布区.水温和海流是影响东海翼足类总丰度分布的主要环境因素.  相似文献   

15.
Temporal variations of the net Kuroshio transport are investigated using long-term hydrographic data from repeat section of the 137°E meridian from the south of Japan (34°N) to New Guinea (1°S) conducted by the Japan Meteorological Agency. In this study, boundaries of the Kuroshio and the Kuroshio Counter Current (KCC) are defined based on the sea surface dynamic height distribution. Westward flows associated with the KCC and cold-core eddy north of the Kuroshio are removed from the eastward flow associated with the Kuroshio in order to estimate the net Kuroshio transport strictly. The net Kuroshio transport reveals low-frequency variations: significant signals on a decadal (about 10-year) timescale. The variations of net Kuroshio transport are predominantly caused by changes in the magnitude of oceanic current speed fields associated with a vertical movement of the main pycnocline depth around the southern boundary of the Kuroshio: deepening of the main pycnocline around the southern boundary of the Kuroshio forms a sharp northern upward-tilting slope of the isopycnal surfaces at the Kuroshio region, and eventually the net Kuroshio transport increases together with the Kuroshio eastward transport. By using a wind-driven hindcast model, it is found that the main pycnocline depth variation results from the first-mode baroclinic Rossby waves attributable to two types of Aleutian Low (AL) changes: a change in the magnitude of AL and meridional movement of AL.  相似文献   

16.
Ciliates play a curial role in energy transfer from pico-and nano-phytoplankton to mesozooplankton in marine ecosystems. In order to visualize their geographical distributions from the Java Sea to the South China Sea (6°S to 20°N), the authors investigated the ciliate abundance and species composition in surface waters during May 18 to 27 of 2010. The ciliate abundance decreased latitudinally from 3 080 ind./L (~6°S) to 40 ind./L (~3°N), and then increased to 1 180 ind./L (~16°N) at the end of the survey. A total of 22 ciliates belonging to 15 genera were identified with the tintinnids accounted for 50% (11 species); and the species number showed a same spatial change as the ciliate abundance. Moreover, the Strombidium occupied over 50% of total ciliate abundance in most stations and Mesodinium and Tintinnopsis contributed to about 18.7% and 11.4%, respectively. In particular, our results indicate that the geographical changes in ciliate abundance were positively regulated by larger nano-and micro-phytoplankton biomass, rather than smaller pico-phytoplankton in the investigated waters.  相似文献   

17.
热带西太平洋雨水的氢、氧同位素组成   总被引:7,自引:0,他引:7  
测定了西太平洋(7.5°~31°N,123°~132°E)1989年9~10月间雨水的δD和δ18O值,结果表明该区雨水的氢、氧同位素组成呈观与中、高纬度地区明显不同的分布特征.雨水的δ值与降水点的纬度没有直接的因果关系,而与季风流场明显相关.沿季风流动方向雨水的δ值逐渐减低,这可用降水云团的瑞利分馏过程解释.雨水δD和δ18O的分布大致反映了研究区季风流场的特征.  相似文献   

18.
The seasonal and interannual changes in surface nutrients, dissolved inorganic carbon (DIC) and total alkalinity (TA) were recorded in the North Pacific (30–54°N) from 1995 to 2001. This study focuses on the region north of the subarctic boundary (∼40°N) where there was extensive monthly coverage of surface properties. The nutrient cycles showed large interannual variations in the eastern and western subarctic gyres. In the Alaska Gyre the seasonal depletion of nitrate (ΔNO3) increased from 8–14 μmol kg−1 in 1995–1999 to 21.5 μmol kg−1 in 2000. In the western subarctic the shifts were similar in amplitude but more frequent. The large ΔNO3 levels were associated with high silicate depletions, indicating enhanced diatom production. The seasonal DIC:NO3 drawdown ratios were elevated in the eastern and central subarctic due to calcification. In the western subarctic and the central Bering Sea calcification was significant only during 1997 and/or 1998, two El Ni?o years. Regional C/N stoichiometric molar ratios of 5.7 to 7.0 (>40°N) were determined based on the years with negligible or no calcification. The annual new production (NPa) based on ΔNO3 and these C/N ratios showed large interannual variations. NPa was usually higher in the western than in the eastern subarctic. However, values of 84 gC m−2yr−1 were found in the Alaska Gyre in 2000 which is similar to that in the most productive provinces of the northern North Pacific. There were also large increases in NPa around the Alaska Peninsula in 1997 and 1998. Finally, the net removal of carbon by the biological pump was estimated as 0.72 Gt C yr−1 in the North Pacific (>30°N). This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

19.
The atmospheric, primary down-column and sedimentary fluxes of particulate aluminium (Alp) have been calculated for a number of regions in the Atlantic Ocean.The vertical down-column flux of Alp from Atlantic surface waters exhibits a strong geographical variation, and its magnitude is influenced by supply mechanisms, which control the surface Alp concentrations, and primary production, which affects the rate of down-column transport. Overall, the down-column transport of Alp is greatest in the marginal regions of the Atlantic. In the eastern margins the highest surface water concentrations are found in the region lying between ~30°N and ~10°N, i.e. under the general path of the northeast trades. In this region there is excellent agreement between the dry (i.e. 1 cm?1 s?1 deposition velocity) atmospheric flux (~80 000 ng Alp cm?2 y?1), the primary vertical down-column flux (? 70 000 ng Alp cm?2 y?1) and the sediment flux (~90 000 ng Alp cm?2 y?1). In the regions to the north (i.e. ~40°N to ~30°N) and to the south (i.e. ~10°N to ~5°S) the primary down-column Alp flux decreases to an average of ~19 000 μg cm?2 y?1, which makes a direct maximum contribution of ~20% of the sediment Alp requirement. In the open-ocean South Atlantic the primary down-column flux of Alp is ~3300 μg cm?2 y?1, this is similar to the dry (i.e. 1 cm?1 s?1 deposition velocity) atmospheric flux, and contributes ~20% of the Alp required by the underlying deep-sea sediment.  相似文献   

20.
The variation features of the Antarctic sea ice (Ⅱ)   总被引:1,自引:0,他引:1  
ThevariationfeaturesoftheAntarcticseaice(Ⅱ)¥XieSimei;HaoChunjiang;QianPingandZhangLin(ReceivedFebruary6,1993;acceptedAugust29...  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号