表面波浪对海洋上层混合的作用     

WANG Zhifeng  WU Kejian  XIA Changshui  ZHANG Xiaoshuang 《海洋学报(英文版)》2014,33(9):32-39

A new three-dimensional numerical model is derived through a wave average on the primitive N-S equations, in which both the＂Coriolis-Stokes forcing＂ and the＂Stokes-Vortex force＂ are considered. Three ideal experiments are run using the new model applied to the Princeton ocean model （POM）. Numerical results show that surface waves play an important role on the mixing of the upper ocean. The mixed layer is enhanced when wave effect is considered in conjunction with small Langmuir numbers. Both surface wave breaking and Stokes production can strengthen the turbulent mixing near the surface. However, the influence of wave breaking is limited to a thin layer, but Stokes drift can affect the whole mixed layer. Furthermore, the vertical mixing coefficients clearly rise in the mixed layer, and the upper ocean mixed layer is deepened especially in the Antarctic Circumpolar Current when the model is applied to global simulations. It indicates that the surface gravity waves are indispensable in enhancing the mixing in the upper ocean, and should be accounted for in ocean general circulation models.  相似文献   

南海中沙群岛海域温盐结构时空变化特征及其控制因素   总被引：1，自引：0，他引：1  

黄诚  吴能友  吴晓  刘时桥  张经纬  许丞  刘亮  董新柱  陈靓 《海洋地质与第四纪地质》2022,42(2):1-14

南海中沙群岛海域夏秋季水团实测温盐深数据统计分析结果表明,研究区海水表层温度为30.0～31.2?℃,最高温度位于中沙海台区域;表层盐度为33.6～34.1?PSU,最高盐度分布在西北部东岛海域附近;底层温度1～25?℃,盐度34.1～35.2?PSU,最高盐度分布在工区东南角.总体上,研究区水团温盐结构表现为表层高温...  相似文献   

南海神狐海域水合物三相混合层测井评价方法研究     

谢莹峰  陆敬安  匡增桂  康冬菊  王通  蔡慧敏 《现代地质》2022,36(1):182-192

天然气水合物降压试采过程中,水合物、游离气和水的三相混合层中的游离气首先被采出,从而提高降压效率,促进水合物分解;因此利用岩心刻度测井的方法开展南海神狐海域水合物三相混合层测井评价方法研究,对水合物矿体储量计算以及产业化开采具有重要意义.三相混合层与水合物层相比,其密度和中子孔隙度值均减小,纵波速度明显下降;与气层相比...  相似文献   

影响南海混合层盐度季节变化的因素分析   总被引：2，自引：0，他引：2       下载免费PDF全文

郭敬  陈显尧  张远凌 《海洋科学进展》2013,31(2)

通过对1950-2012年的南海混合层盐度数据进行分析,发现影响南海北部和南部盐度季节变化的最主要因素存在很大的差异.在南海北部,影响混合层盐度季节变化的最主要因素是蒸发降水,其次是水平平流.随着逐步南移,蒸发降水对盐度季节变化的影响递减,水平平流的影响逐渐增大;而在南海南部,水平平流的作用超过蒸发降水成为影响盐度的季节变化的最主要因素.在整个南海区域,冬季海水垂直混合变强,混合层变厚,下层高盐海水进入混合层,使混合层海水盐度变高,从而对冬季海水盐度的上升趋势产生促进作用;夏季南海北部混合层底存在上升流,南海东南部由于Ekman输运导致混合层变厚,都会将混合层以下高盐海水带入混合层,使混合层海水盐度变高,从而对夏季海水盐度下降趋势产生阻碍作用,但垂直混合对盐度季节变化的影响不大,远小于蒸发降水和水平平流.  相似文献   

不同混合层深度算法的全球适用性对比分析          下载免费PDF全文

王学华  程灵巧  张春玲  李宏 《海洋通报》2023,(3):279-289

混合层深度是研究海洋上层动力过程及海气相互作用的一个至关重要的物理量,准确估算混合层深度对上层海洋动力学和热力学的深入研究具有重要的科学意义。本文基于Argo实时观测剖面数据,分海域、分季节对比分析了目前常用的几种混合层深度算法的异同与优缺点。结果表明,理论上最大角度法的精确度最高,曲率法其次,然后是阈值法和最优线性拟合法。最大角度法和曲率法的结果比较接近,实测数据表明曲率法的时空适用性更广。阈值法、最优线性拟合法分别受梯度阈值和密度（或温度）梯度变化的制约,其计算的混合层深度相对较浅。各种算法的差异性随着季节跃层的增强而逐渐减小,且北半球的差异小于南半球。  相似文献   

四套高分辨率再分析海洋-海冰资料在罗斯海和阿蒙森海的评估          下载免费PDF全文

黄佳  张召儒  王小乔 《极地研究》2020,32(4):452-468

  相似文献   

南海风生近惯性能通量的敏感性分析     

孙宝楠  连展  袁业立  徐海洋 《海洋学报(英文版)》2019,38(4):136-145

After validated by the in-situ observation, the slab model is used to study the wind-generated near-inertial energy flux(NIEF) in the South China Sea(SCS) based on satellite-observed wind data, and its dependence on calculation methods and threshold criteria of the mixed layer depth(MLD) is investigated. Results illustrate that the total amount of NIEF in the SCS could be doubled if different threshold criteria of MLD are adopted. The NIEF calculated by the iteration and spectral solutions can lead to a discrepancy of 2.5 GW(1 GW=1×109 W). Results also indicate that the NIEF exhibits spatial and temporal variations, which are significant in the boreal autumn,and in the southern part of the SCS. Typhoons are an important generator of NIEF in the SCS, which could account for approximately 30% of the annual mean NIEF. In addition, deepening of the MLD due to strong winds could lead to a decrease of NIEF by approximately by 10%. We re-estimate the annual mean NIEF in the SCS,which is(10±4) GW and much larger than those reported in previous studies.  相似文献   

盐度对变化2014年东北太平洋“暖泡”的作用   总被引：1，自引：0，他引：1  

智海  林鹏飞  张荣华  柴菲  刘海龙 《海洋学报(英文版)》2019,38(9):24-34

A significant strong, warm "Blob"(a large circular water body with a positive ocean temperature anomaly)appeared in the Northeast Pacific(NEP) in the boreal winter of 2013–2014, which induced many extreme climate events in the US and Canada. In this study, analyses of the temperature and salinity anomaly variations from the Array for Real-time Geostrophic Oceanography(Argo) data provided insights into the formation of the warm"Blob" over the NEP. The early negative salinity anomaly dominantly contributed to the shallower mixed layer depth(MLD) in the NEP during the period of 2012–2013. Then, the shallower mixed layer trapped more heat in the upper water column and resulted in a warmer sea surface temperature(SST), which enhanced the warm"Blob". The salinity variability contributed to approximately 60% of the shallowing MLD related to the warm"Blob". The salinity anomaly in the warm "Blob" region resulted from a combination of both local and nonlocal effects. The freshened water at the surface played a local role in the MLD anomaly. Interestingly, the MLD anomaly was more dependent on the local subsurface salinity anomaly in the 100–150 m depth range in the NEP.The salinity anomaly in the 50–100 m depth range may be linked to the anomaly in the 100–150 m depth range by vertical advection or mixing. The salinity anomaly in the 100–150 m depth range resulted from the eastward transportation of a subducted water mass that was freshened west of the dateline, which played a nonlocal role.The results suggest that the early salinity anomaly in the NEP related to the warm "Blob" may be a precursor signal of interannual and interdecadal variabilities.  相似文献   

南海上层热含量的年代际变化及影响因子分析     

宋伟  王玉  崔凤娟  谢强 《海洋与湖沼》2019,50(4):752-758

南海上层海洋热力结构年代际变化的研究,是海气相互作用与变化研究的热点之一,对南海区域及更大范围的气候异常的研究和南海海洋环流年际变化的研究都具有重要意义。本文采用多套海温、流场和海气界面通量资料,基于热平衡方程和统计分析方法,分析了南海上层热含量的年代际变化,研究了南海上层热含量影响因子的变化特征,比较了混合层及混合层以下热含量变化的异同,进而探讨了影响因子在混合层及混合层以下的不同作用;利用区域积分海温方程后得到的热量收支方程,诊断南海内区不同海域的热收支方程中的各项,发现了不同海域在影响热收支的物理过程方面存在差异。结果表明:南海混合层的热含量的变化主要受海气界面热通量的影响,夹卷效应在热含量的变化中也有接近1/3的贡献。在整个上层400m的热含量变化中,平流效应占据了主导地位。  相似文献   

全球气候模式对影响西北太平洋台风强度的大尺度环境因子的模拟评估     

《干旱气象》2021,39(3)

基于NOAA和NCEP再分析资料以及CMIP5(coupled model intercomparison project phase5)模式历史试验输出结果,首先评估模式对控制台风强度的大尺度环境因子空间分布的模拟能力,然后在台风主要发展区域,评估模式对环境因子的空间分布和时间变化特征的模拟能力。结果表明:CESM1-BGC,CESM1-CAM5和CNRM-CM5能模拟出观测的海表面温度气候分布和上升特征;CCSM4,CESM1-BGC和CESM1-CAM5能模拟出观测的混合层厚度气候分布和增厚特征;ACCESS1-0,ACCESS1-3,CanESM2和GFDL-ESM2M能模拟出观测流出层温度气候分布和下降特征,但模拟的下降率小。ACCESS1-0,CESM1-CAM5,CNRM-CM5,MPI-ESM-MR和GFDL-ESM2G能模拟出观测垂直风切变的气候分布和趋势特征。综合评估表明CESM1-BGC和CESM1-CAM5可用来研究西北太平洋台风强度的气候变化问题。  相似文献