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1.
为深入研究垂线偏差在海域的精度水平,在我国渤海近海区域利用数字天顶仪及精密单点定位技术测量获得了若干高精度垂线偏差测量值,利用测量值对EGM2008模型、Jason-1卫星数据、DTU10海面高模型及点质量模型计算得到的垂线偏差进行了比对分析。以测量结果为基准,比较结果表明,EGM2008模型的计算结果相对较好,Jason-1卫星数据和点质量模型次之,DTU10海面高计算结果较差。以长岛观测点为代表,EGM2008模型、Jason-1卫星数据、点质量模型计算的垂线偏差与数字天顶仪测量获得的垂线偏差的差异(子午和卯酉两个方向)在1. 5″以内。  相似文献   

2.
本文分析处理了TOPEX/POSEIDON卫星1~82周期的测高数据。重新计算了逆气压改正数;利用共线法计算的TOPEX和POSEIDON之间相对偏差估值为19.9±1cm;将编辑后的海面高与Basic和Rapp计算的平均海面高进行比较,发现二者之间存在明显的系统偏差。  相似文献   

3.
史剑  蒋国荣 《海洋与湖沼》2015,46(6):1255-1262
风浪状态参数常用于对海面粗糙度的参数化。中等风速条件下考虑风浪状态参数影响的海面粗糙度参数化方案常存在自相关效应,本文通过分析实测数据得到了无量纲粗糙度随波陡变化的参数化方案,该方案能够有效去除自相关效应;高风速下风浪状态对海面粗糙度仍存在影响,文中基于新得出的中等风速下的海面粗糙度参数化方案,考虑海面飞沫悬浮层的影响,建立了适用于高风速条件下的海面粗糙度参数化方案,该海面粗糙度方案同样考虑了波陡的作用,将该方案计算出的理论值与实测数据进行比对,发现随着波陡的变化,理论值基本涉及测量值的覆盖范围,说明新建立的高风速条件下海面粗糙度方案对海面风浪状态具有较好的敏感性,且该方案能够较合理地描述海气界面之间动量传输。将新提出的适用于高风速下的海面粗糙度方案加入到海浪数值模式中,模拟飓风Ivan产生的台风浪,利用浮标数据进行验证,结果显示模拟的有效波高相对模式默认方案具有较高的精度,说明采用本文新建立的适合高风速的海面粗糙度方案能够改进海浪模式的台风浪有效波高模拟结果。  相似文献   

4.
到目前,还缺乏关于大型陆架系统对全球海面变化响应的研究,5年来我们对中国东部宽阔的陆架海底进行详细制图研究,结果表明:现代中国东部陆架海底沉积环境分布与末次冰盛期以来的海面变化之间有很好的响应关系;目前的陆架海底被3个沉积体系覆盖,即低海面期的古滨带、冰消期的海侵体系和高海面期的涡漩及近岸带沉积体系;末次冰期后期以来,可区分出3个快速海面上升期和3个慢速上升期。在快速上升期,海底形成了代表海岸快速移动的混杂沉积-海侵边界层,海岸平均移动速度10~22cm/a(最大64cm/a),缓慢上升期,形成了陆架广泛分布的潮流沙脊体系,三期沙脊体系之间有继承性演化关系。  相似文献   

5.
海面风速微波散射测量与分析   总被引:3,自引:0,他引:3  
为了深入研究海面风的微波散射特性 ,利用海洋石油平台和飞机作为仪器的工作平台 ,对海面微波散射特性进行了测量 ,并应用统计分析方法 ,对测量数据作处理分析。结果表明 ,海面微波后向散射系数 (σ°)值与海面风速成线性关系 ,随风速增大而增大。同时 ,σ°值与夹角及散射计天线入射角、极化方式有关。结合对海面微波散射算法中 Phillips模式的分析比较 ,得到 Phillips模式的计算值与实测值变化趋势一致的结果  相似文献   

6.
从渤海到南海分布的几十至上百米宽的海蚀平台、与全新世类高的晚更新世海积地面和同期滨海相粘性土的顶面高程,是确定晚更新世、尤其是距今4万至2万年中国海的高海面接近现在海面的3项古海面遗迹证据。选择证据以大陆海岸、岩岸和沙坝湖海岸为主。三角洲平原的晚更新世中期海相粘性土的顶面高程偏低,是由于沉积物压实、冰期低海山时被流水蚀低和构造下沉3个因素造成的,可通过复原获得改正。  相似文献   

7.
根据线性滤波器模型的基本原理,提出了一种改进的基于高阶滤波器的随机起伏海面仿真方法.利用Pierson的半经验海浪谱模型,得到了各种不同风速条件下海面随机起伏的仿真结果,并且对仿真结果进行了比较和讨论,结果表明,利用高阶滤波器方法能更加准确地仿真不同风速下的实际海面、更好地再现随机起伏海面的海浪谱特征.这一方法的提出为海浪的物理模拟实验提供了更为准确的数值计算方法,也为研究目标与海面共存条件下高频地波雷达信号的回波特性提供了更好的数值仿真平台.  相似文献   

8.
近岸区域及河口区台风风场动力诊断模型   总被引:2,自引:0,他引:2  
由梯度风平衡原理得出具有非对称性的台风模型风场 ,将台风模型风场与 NCAR客观分析风场嵌套得到大区风场并从中取出中尺度动力诊断模式 Mass所需的初始风场 ,再由 Mass模式对局部关键性区域海面风场作动力调整 ,同时结合实测资料使用 Nudging同化方法进行调整 ,从而获得具有较好实用性的台风近岸及河口区的海面风场。文中用上述模型对 90 15号和 9711号台风作了诊断分析试验 ,得到了比较合理的并符合实际观测的台风海面风场  相似文献   

9.
研究了海面高因素对北斗系统定位精度的影响,并利用“三星+高程约束法”、“星际差分+初始高程约束法”和“余弦定理解析求解法”三种解算方法进行仿真计算,计算结果表明,考虑海面高因素能有效地提高北斗系统定位精度且提高幅度与解算方法有关。  相似文献   

10.
稳态海面地形(MDT)是大地测量学家和海洋学家共同关心的一个重要物理量。该文基于WHU2009全球平均海面高模型和GO_CONS_GCF_2_TIM_R3纯GOCE重力场模型,采用几何法经高斯滤波处理后确定了全球稳态海面地形,与CLS09及DTU10M DTs相比,其差值均方根RMS均小于8 cm,表明该文结果具有较高的精度;根据地转流方程计算了相应的表层地转流,与GRACE重力场模型GGM03S结果相比,GOCE重力场模型所确定的表层地转流在墨西哥湾流、黑潮及厄加勒斯海流等海域均体现了更强的流速和更多的细部特征,验证了GOCE在洋流探测中的优势。  相似文献   

11.
Wanshan area has been chosen to be the specified field to calibrate and validate(Cal/Val) the HY-2 altimeter and its follow-on satellites. In March 2018, an experiment has been conducted to determine the sea surface height(SSH) under the HY-2 A ground track(Pass No. 203). A GPS towing-body(GPS-TB) was designed to measure the SSH covering an area of about 6 km×28 km wide centered on the HY-2 A altimeter satellite ground track. Three GPS reference stations, one tide gauge and a GPS buoy were placed in the research area, in order to process and resolve the kinematic solution and check the precision of the GPS-TB respectively. All the GPS data were calculated by the GAMIT/GLOBK software and TRACK module. The sea surface was determined by the GPS-TB solution and the tide gauge placed on Zhiwan Island. Then the sea surface of this area was interpolated by Arc GIS10.2 with ordinary Kriging method. The results showed that the precision of the GPS-TB is about 1.10 cm compared with the tide gauge placed nearby, which has an equivalent precision with the GPS buoy. The interpolated sea surface has a bias of –1.5–4.0 cm with standard deviation of 0.2–2.4 cm compared with the checking line. The gradient of the measured sea surface is about 1.62 cm/km along the HY-2 orbit which shows a good agreement compared with the CLS11 mean sea surface(MSS). In the Cal/Val of satellites, the sea surface between the tide gauge/GPS buoy and the footprint of altimeter can be improved by this work.  相似文献   

12.
借助伴随同化方法,利用实测水位资料,对空间分布的风应力拖曳系数做了反演研究.假定风应力拖曳系数具有空间分布特征,即在模拟海区中均匀选取一些独立点,利用这些独立点的风应力拖曳系数线性插值得到全场的风应力拖曳系数.同化实验结果表明,采用空间分布的风应力拖曳系数得到的模拟结果,明显优于将风应力拖曳系数取为常数和依照经验公式计...  相似文献   

13.
We present an improved crossover adjustment procedure to determine mean sea surface height using TOPEX, 35-day repeat phase ERS-1, Geosat, and 168-day repeat phase ERS-1 satellite altimeter data. The mean sea surface frame defined by the TOPEX data is imposed as certain constraints in our crossover adjustment procedure rather than held fixed as in some other procedures. The new procedure is discussed in detail. Equations are developed to incorporate the a priori information of Topex data as well as other satellite altimeter data. The numerical computation result shows that the rms crossover discrepancies are reduced by an order of 1 cm when the Topex data is not fixed. Furthermore, the computed mean sea surface is less noisy and more realistic than that computed by the traditional procedure.  相似文献   

14.
We present an improved crossover adjustment procedure to determine mean sea surface height using TOPEX, 35-day repeat phase ERS-1, Geosat, and 168-day repeat phase ERS-1 satellite altimeter data. The mean sea surface frame defined by the TOPEX data is imposed as certain constraints in our crossover adjustment procedure rather than held fixed as in some other procedures. The new procedure is discussed in detail. Equations are developed to incorporate the a priori information of Topex data as well as other satellite altimeter data. The numerical computation result shows that the rms crossover discrepancies are reduced by an order of 1 cm when the Topex data is not fixed. Furthermore, the computed mean sea surface is less noisy and more realistic than that computed by the traditional procedure.  相似文献   

15.
海上不同高度风速换算关系的研究   总被引:1,自引:0,他引:1  
本文用海上石油平台上观测的风梯度资料,计算了在不同风况下海面摩擦速度和粗糙高度。结果表明,海面摩擦速度u_*与海上10m高度处风速u_(10)的关系为u_*=0.055u_(10)-0.058。在4—5级风时,海面平均摩擦速度为50cm/s,粗糙度为0.022m,它相当于陆上的平均粗糙高度。在风速为2—3级时,二者与海上通常采用的数据接近。文中最后给出了上述两种风况下海上不同高度的换算系数。  相似文献   

16.
1 .IntroductionTheglobalairtemperatureroseabout 0 .5~ 0 .6°Coverthepast 2 0thcentury ,andtheglobalmeansealevelincreasedbyabout2 0cmduringtheperiod .Theregionalmeansealevelriseswiththerisingglobalmeansealevel.Zuoetal.( 1 997)indicatedthatthemeanrisingrateofabsolutemeansealevelalongtheChinacoastontheassumptionofunifiedisostaticdatumis 2mm a .Woodworth( 1 999)analyzedsealevelspanning 1 76 8tothepresentinLiverpool,andobtainedaseculartrendforheperiodupto 1 880of0 .39± 0 .1 7mm a ,andatrendfort…  相似文献   

17.
Historical observations of the surface current and daily mean sea level during the period 1965–1985 are analyzed in order to examine the geostrophic balance of the Kuroshio current in the Tokara Strait and near the Izu Islands. The variation in the sea level difference across the Kuroshio is associated with a variation in surface current velocity as predicted by the theory of geostrophic balance. However, the slope of the linear relation between the current velocity and sea level difference is smaller than the theoretically predicted value by about 30%. This disagreement may be ascribed to the effects of the centrifugal force and the occasional rise in sea level due to storm surges.Absolute mean sea level differences between the tidal stations are estimated by making use of the empirical relationship between the surface current and sea level difference. Estimated differences are: 87.4±22.1 cm between Naze and Nishinoomote, 24.3±9.2 cm between Miyake and Minamiizu, 41.3±17.7 cm between Miyake and Mera and 45.1±8.8 cm between Hachijyo and Miyake. The absolute value of sea level difference between Miyake and Minamiizu and that between Miyake and Mera may be about 30 cm, since geodetic levelling tells us that the mean sea level at Minamiizu is nearly equal to that at Mera.  相似文献   

18.
Variability of Sea Surface Circulation in the Japan Sea   总被引:3,自引:0,他引:3  
Composite sea surface dynamic heights (CSSDH) are calculated from both sea surface dynamic heights that are derived from altimetric data of ERS-2 and mean sea surface that is calculated by a numerical model. The CSSDH are consistent with sea surface temperature obtained by satellite and observed water temperature. Assuming the geostrophic balance, sea surface current velocities are calculated. It is found that temporal and spatial variations of sea surface circulation are considerably strong. In order to examine the characteristics of temporal and spatial variation of current pattern, EOF analysis is carried out with use of the CSSDH for 3.5 years. The spatial and temporal variations of mode 1 indicate the strength or weakness of sea surface circulation over the entire Japan Sea associated with seasonal variation of volume transport through the Tsushima Strait. The spatial and temporal variations of mode 2 mostly indicate the temporal variation of the second branch of the Tsushima Warm Current and the East Korean Warm Current. It is suggested that this variation is possibly associated with the seasonal variation of volume transport through the west channel of the Tsushima Strait. Variations of mode 3 indicate the interannual variability in the Yamato Basin.  相似文献   

19.
根据1999—2001年月平均海面高度资料讨论了青岛和胶州湾附近海面高度的年变化。结果表明:各验潮点夏季的海面高度普遍高于冬季的海面高度,具有明显的季节变化。此外,夏季胶州湾口外的海面高度低于胶州湾内的海面高度,表现为由北向南下倾的海面坡度。同时说明了形成这利海面坡度的原因。文章还利用动力学原理探讨了夏季风和海面坡度的动力作用,及其对月平均海流的影响,强调指出了夏季风和海面坡度所产生的压强梯度力的重要性。  相似文献   

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