An East Asian Subtropical Summer Monsoon Index Defined by Moist Potential Vorticity   总被引：1，自引：1，他引：0  

丛宽  毕云 《热带气象学报(英文版)》2011,17(1):11-17

Based on consideration of both thermodynamic and kinetic features of the subtropical summer monsoon in East Asia,a new index is defined by the moist potential vorticity (MPV) for this monsoon.Variation features of the subtropical summer monsoon over 60 years are analyzed using National Centers for Environmental Prediction/National Center for Atmospheric Research (USA) data from 1948 to 2007.Results show that the new index can well reflect the seasonal,interannual,and interdecadal variations of the East Asian subtropical summer monsoon.Correlation analysis of the new index and precipitation data from 160 stations in China shows that in high-index years,the summer monsoon is strong,and more rain falls in eastern North China,southwestern China,and along the coast of South China and less rain falls in the Yangtze-Huaihe R.basin.In low-index years,the opposite occurs.Lastly,the new index is compared with four established monsoon indices.The new index is found to have an advantage in representing summer rainfall in the Yangtze-Huaihe R.basin.  相似文献   

未来黄、东海营养盐浓度变化情景预测   总被引：1，自引：0，他引：1  

赵一丁  杨波  魏皓  赵亮 《海洋与湖沼》2015,46(5):983-994

本文基于FGOALS(Flexible Global Ocean-Atmosphere-Land System model)对未来气候情景的预测结果,结合千年生态评估的未来两个情景下的河流营养盐载荷特征,利用黄、东海水动力模型和生态模型并采用降尺度的方法对未来黄、东海营养盐的分布特征进行情景预测。结果表明,两个情景下未来河口邻近海区营养盐浓度将显著增加,富营养化加剧;GO(Global Orchestration)情景下,河流无机氮载荷增幅较大,夏季黄海中部无机氮浓度明显升高;AM(Adapting mosaic)情景下,由于河流无机磷载荷增幅较大,海区氮磷比有所下降,夏季黄海中部表层无机氮浓度降低,而在底层升高。通过敏感性实验并结合收支分析对各海区水动力条件未来变化、河流载荷变化的相对贡献进行了评估:相对于水温和水动力环境改变,河流营养盐排放量的增长是未来营养盐浓度增加的主要原因。营养盐收支分析表明,未来对流和混合输运的变化有助于黄海营养盐浓度的增加,夏季生物量升高造成更多碎屑沉降并在底层矿化使得层化季节冷水团底部营养盐浓度增长;长江口邻近海区营养盐浓度增长主要受冲淡水羽流的影响;净初级生产增加加剧了营养盐的消耗。  相似文献   

秋季东海溶解态和颗粒态氨基酸的分布与组成_*     

张鹏燕  陈岩  杨桂朋 《海洋与湖沼》2015,46(2)

本文对2012年秋季中国东海31个站位的海水样品中溶解态氨基酸（THAA）和颗粒态氨基酸（PAA）的分布与组成进行了研究。结果表明：表层海水中溶解游离氨基酸(DFAA)的平均浓度为0.12±0.04 μmol/L (0.06~0.19 μmol/L),溶解结合氨基酸(DCAA)的平均浓度为0.61±0.51 μmol/L (0.15~1.79 μmol/L),PAA的平均浓度为0.11±0.06 μmol/L (0.02~0.27 μmol/L)。THAA的水平分布特点大致为近岸高、远岸低;PAA的水平分布特点是近岸海域向远海海域分布呈现逐渐减小的趋势。THAA的垂直分布特点是由表层向底层逐渐降低。DCAA、PAA与Chl-a有很好的相关性,而DFAA与Chl-a的相关性不明显。东海表层海水中THAA的主要组分是天门冬氨酸、谷氨酸、丝氨酸、甘氨酸、苏氨酸及丙氨酸,PAA的主要组分是天门冬氨酸、谷氨酸、丝氨酸、甘氨酸、丙氨酸及亮氨酸。在表层海水中氨基酸是作为一个整体而对海洋生物地球化学过程产生影响的。  相似文献   

Macrobenthos relative to the oxygen minimum zone on the East Indian margin,Bay of Bengal          下载免费PDF全文

Akkur V. Raman  Rayaroth Damodaran  Lisa A. Levin  Thiruchitrambalam Ganesh  Yannamani K. V. Rao  Sateesh Nanduri  Rakhesh Madhusoodhanan 《Marine Ecology》2015,36(3):679-700

The Bay of Bengal remains one of the least studied of the world's oxygen minimum zones (OMZs). Here we offer a detailed investigation of the macrobenthos relative to oxygen minimum zone [OMZ – DO (dissolved oxygen), concentration <0.5 ml·1^?1] at 110 stations off the North East Indian margin (16⁰ and 20⁰ N) featuring coastal, shelf and slope settings (10–1004 m). Macrobenthos (>0.5 mm) composition, abundance and diversity were studied in relation to variations in depth, dissolved oxygen, sediment texture and organic carbon. Using multivariate procedures powered by SIMPROF analysis we identified distinct OMZ core sites (depth 150–280 m; DO 0.37 ml·1^?1) that exhibited dense populations of surface‐feeding polychaetes (mean 2188 ind. m^?2) represented by spionids and cossurids (96%). Molluscs and crustaceans were poorly represented except for ampeliscid amphipods. The lower OMZ sites (DO > 0.55 ml·l^?1) supported a different assemblage of polychaetes (cirratulids, amphinomids, eunicids, orbinids, paraonids), crustaceans and molluscs, albeit with low population densities (mean 343 ind. m^?2). Species richness [E(S₁₀₀)], diversity (Margalef d; H’) and evenness (J’) were lower and dominance was higher within the OMZ core region. Multiple regression analysis showed that a combination of sand, clay, organic carbon, and dissolved oxygen explained 62–78% of the observed variance in macrobenthos species richness and diversity: E(S₁₀₀) and H’. For polychaetes, clay and oxygen proved important. At low oxygen sites (DO <1 ml·l^?1), depth accounted for most variance. Residual analysis (after removing depth effects) revealed that dissolved oxygen and sediment organic matter influenced 50–62% of residual variation in E(S₁₀₀), H’ and d for total macrofauna. Of this, oxygen alone influenced up to ~50–62%. When only polychaetes were evaluated, oxygen and organic matter explained up to 58–63%. For low oxygen sites, organic matter alone had the explanatory power when dominance among polychaetes was considered. Overall, macrobenthic patterns in the Bay of Bengal were consistent with those reported for other upwelling margins. However, the compression of faunal gradients at shallower depths was most similar to the Chile/Peru margin, and different from the Arabian Sea, where the depth range of the OMZ is two times greater. The Bay of Bengal patterns may take on added significance as OMZs shoal globally.  相似文献   

黄东海表层沉积物中磷的赋存形态和分布特征及其对生态系统的潜在影响   总被引：2，自引：0，他引：2  

宋国栋  刘素美 《海洋学报(英文版)》2015,34(4):84-91

For better understanding the phosphorus(P) cycle and its impacts on one of the most important fishing grounds and pressures on the marine ecosystem in the Yellow Sea(YS) and East China Sea(ECS), it is essential to distinguish the contents of different P speciation in sediments and have the knowledge of its distribution and bioavailability. In this study, the modified SEDEX procedure was employed to quantify the different forms of P in sediments. The contents of phosphorus fractions in surface sediments were 0.20–0.89 μmol/g for exchangeable-P(Exch-P), 0.37–2.86 μmol/g for Fe-bound P(Fe-P), 0.61–3.07 μmol/g for authigenic Ca-P(ACa-P), 6.39–13.73μmol/g for detrital-P(DAP) and 0.54–10.06 μmol/g for organic P(OP). The distribution of Exch-P, Fe-P and OP seemed to be similar. The concentrations of Exch-P, Fe-P and OP were slightly higher in the Yellow Sea than that in the East China Sea, and low concentrations could be observed in the middle part of the ECS and southwest off Cheju Island. The distribution of ACa-P was different from those of Exch-P, Fe-P and OP. DAP was the major fraction of sedimentary P in the research region. The sum of Exch-P, Fe-P and OP may be thought to be potentially bioavailable P in the research region. The percentage of bioavailable P in TP ranged from 13% to 61%. Bioavailable P burial flux that appeared regional differences was affected by sedimentation rates, porosity and bioavailable P content, and the distribution of bioavailable P burial flux were almost the same as that of TP burial flux.  相似文献   

中国东海海平面长期变化与趋势研究     

徐莹  林明森  郑全安  叶小敏  李君益  朱本璐 《海洋学报(英文版)》2015,34(11):109-117

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.  相似文献   

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

JUN Ki Cheon  JEONG Weon Mu  CHOI Jin Yong  PARK Kwang Soon  JUNG Kyung Tae  KIM Mee Kyung  CHAE Jang Won  QIAO Fangli 《海洋学报(英文版)》2015,34(12):19-28

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 of C_d 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.  相似文献   

东中国海HYCOM模式垂向坐标对比研究     

陈晓斌  周林  陈璇  郑崇伟  吴炎成 《海洋科学》2015,39(7):60-68

基于挪威南森环境遥感中心改进的NERSC-HYCOM 模式, 利用单向嵌套技术与欧洲中心提供的2008 年ERA-I 高分辨率强迫场针对东中国海及其邻近海区进行了不同垂向坐标配置的四个敏感性试验。通过分析东中国海区域的温度、盐度, 流速的分布和变化, 探讨了HYCOM 模式中不同垂向坐标设置对东中国海近岸区域的影响以及黑潮流速及路径对不同坐标设置的响应, 期望对HYCOM 模式更深入的研究提供参考。结果表明: (1)在东中国海区上层并不适于采用等密度坐标方案, 也就是说应该采用z坐标或σ坐标用以表征此处混合层的季节性变化特征; (2)针对东海大陆架区给出了10 个位置上的模式与浮标观测资料的温、盐平均误差(ME)、均方根差(RMS)及相关系数(R)指标, 发现对于不同区域, 每种试验的适用性都不同; (3)使用高频资料时, 模拟的流速普遍偏高, 东海黑潮冬夏路径的异同指出了σ-z-iso 与z-iso 试验模拟效果较好, 但模拟的日本岛南岸的弯曲流场位置偏南; 而z-only 试验模拟的日本岛以南的黑潮路径是有所改观的, z坐标的分辨率对表层的黑潮路径影响很大; σ-only 试验模拟的整个黑潮路径的效果最差。  相似文献   

江苏近岸紫菜养殖筏架区定生绿藻群落结构及其受控因素   总被引：3，自引：1，他引：2  

李艳  肖洁  丁兰平  王宗灵  宋伟  方松  范士亮  李瑞香  张学雷 《海洋学报(英文版)》2015,34(8):93-99

基于2010年10月至2011年4月对苏北紫菜养殖筏架区定生绿藻及环境因素调查数据,分析研究了紫菜筏架上定生绿藻种群结构和数量变化及重要环境因子对其的影响并估算了调查区绿藻总生物量.结果表明,筏架上定生绿藻种类有浒苔(Ulva prolifera)、盒管藻(Capsosiphon groenlandicus)、缘管浒苔(Ulva linza)、肠浒苔(Ulva intestinalis)、条浒苔(Ulva clathrata)和扁浒苔(Ulva compressa).绿藻生物量变化呈倒抛物线型,4月份为主高峰14898吨,11月份为次高峰2034吨,2月份最低,仅为729吨,3-4月份绿藻几乎呈暴发性增长.种类多样性随季节变化有很大差异,养殖筏架刚入海的9、10月份,绿藻种类丰富,生物多样性高;12月至笠年2月,尽管生物量很低,但仍是多种并存;3-4月份随着生物量的猛增,种类多样性降至最低,盒管藻优势地位明显,生物量比例最大能到80%,浒苔比例呈指数增长,达20%～40%.水温对绿藻生物量及种类演替有直接调控作用,在水温< 10℃时,绿藻即能快速生长;而盐度作用不明显.开展紫菜筏架上定生绿藻群落动态变化及其生物量的估算,为追溯南黄海大规模绿潮发源地提供佐证,为绿潮预防和治理提供基础数据支撑.  相似文献   

黄海、东海区域漫衰减系数光谱遥感反演及激光测深性能评估     

李凯  童晓冲  张永生  哈长亮  申二华 《遥感学报》2015,19(5):761-769

本文在总结和比较中国现有黄海、东海海域漫衰减系数反演算法的基础上,利用水色测量数据分析得到漫衰减系数Kd(532)与Kd(490)之间的关系,为激光测深系统(以CZMIL为例)的性能评估提供了基础。利用MODIS二级数据产品评估了中国黄海、东海海域在CZMIL海道测量模式下最大可测水深的空间分布。研究结果表明CZMIL在黄海、东海海域可测水深基本在0—50 m,该区域的面积占研究区域面积的比例为76.2%,为浅海海域开展激光测深作业提供了测深能力评估的依据和方法。  相似文献