全球大洋潮汐模式在北印度洋潮汐预报准确性的评估     

刘经东  张文静  刘春笑  郑后俊  朱首贤  史剑  聂屿 《海洋通报》2019,(2):159-166

为评估DTU10、TPXO8、GOT00.2和NAO.99b 4个全球大洋潮汐模式对北印度洋潮汐的预报能力,采用英国海洋资料中心提供的海区中部和沿岸站潮汐调和常数资料,检验了这些模式4个主要分潮(M_2、S_2、K_1、O_1)的准确度。它们的各分潮调和常数资料准确度都比较高,振幅绝均差的最大值仅5.61 cm,迟角绝均差的最大值仅9.13°。这些模式的调和常数给出潮波传播特征差别不大。基于这些模式提供的调和常数,分别建立了北印度洋4、8和16分潮潮汐预报模型,将预报结果与中国海事服务网提供的沿岸24个站潮汐表资料进行对比。各模式的8分潮(M_2、S_2、N_2、K_2、K_1、O_1、P_1、Q_1)潮汐预报模型均优于4分潮(M_2、S_2、K_1、O_1)潮汐预报模型,NAO.99b模式可以提供16分潮(M_2、S_2、N_2、K_2、K_1、O_1、P_1、Q_1、MU_2、NU_2、T_2、L_2、2N_2、J_1、M1、OO_1)潮汐预报模型,但是对预报结果改善不明显;在各模式中,GOT00.2模式的8分潮潮汐预报模型对北印度洋沿岸的预报效果最好,平均绝均差为14.97 cm。  相似文献   

海表面温度时空变异特征及对验证误差影响     

蒋锦刚  徐曜  聂晨晖  潘骁骏  周斌 《遥感学报》2019,23(2):336-348

海洋要素的变化存在明显的区域性和季节性的变化特性,本文选择海洋要素中最为突出的海表面温度(SST)要素作为主要分析参数,设计时空变异参数的计算指标,分析时空变异对验证误差影响的关系,通过研究及试验的数据精度验证,证明了时空变异是造成误差的直接原因之一。强烈的时空属性变异,在验证过程中会引入很大的验证误差,处于不同变异等级区划的数据,其验证结果相对误差可达13.08%,变异越剧烈的区域,精度验证效果越差,验证误差就越大,这些误差并非完全是遥感产品的误差,验证结果不具有代表性,不能真实的反映遥感产品的误差特征。对于SST等海洋遥感产品验证时,需要考虑时空变异对验证误差的影响和贡献,合理选择验证试验区域、代表性的评价数据集和科学的评价方法。  相似文献   

广角水体体散射函数测量技术及其应用研究进展     

徐聪辉  李彩 《遥感学报》2019,23(6):1078-1090

水体体散射函数是描述水体中光在各方向散射特性的一个重要的固有光学参数,对水色遥感、水环境监测与保护、海气交互过程研究、水下军事目标跟踪等领域具有十分重要的意义。水体体散射函数测量尤其是覆盖0°—180°范围的广角体散射函数测量技术起步较晚,直接测量难度较大,一直以来都是一个棘手的科学难题。本文梳理了国内外广角水体体散射函数测量技术的发展历程,对于广角体散射函数测量技术,从原理上大致可以分为单一探测器转动式、多个固定探测器阵列式以及面阵CCD成像式等3大类,对不同测量原理下的测量技术进行详细分析,并对广角水体体散射函数测量技术在海洋生物光学、气泡跟踪、水色遥感等方面的相关应用进展进行总结和归纳,并对未来广角水体体散射函数的发展趋势和应用前景进行展望。  相似文献   

天津市海洋经济中港口产业发展研究   总被引：1，自引：0，他引：1  

王磊  林宁 《海洋通报》2007,26(4):99-104

作为海洋经济的重要组成部分,港口经济的发展为天津市海洋经济的跨越式发展提供了非常有利的契机。要尽快实现天津港口经济健康、有序、可持续的发展,为天津滨海新区的开发开放提供更强有力的支持,从而实现建设北方国际航运中心和国际物流中心的目标。综合近年来海洋统计的成果,以AHP法为分析方法,对天津港口经济的现状和发展趋势作探讨和研究,指出天津港口经济在未来发展中需要注意的问题,并提出初步解决方案。  相似文献   

南海北部藻类粒级结构及色素成分对浮游植物吸收系数的影响   总被引：2，自引：0，他引：2  

王桂芬  曹文熙  许大志  杨跃忠 《海洋学报》2007,29(1):38-48

在珠江口、广东沿岸及南海北部三个航次生物-光学数据的基础上,研究了色素打包效应和色素成分的变化对浮游植物吸收系数的影响,结果表明,两种因素对吸收系数都有较大的贡献,但在不同的水体它们的影响程度各有不同.对网采浮游植物含量较高的珠江口和广东沿岸的水体而言,色素打包效应较强,对675 nm处比吸收系数的贡献平均分别为40%和20%;对微型浮游植物占主导地位的南海北部航次的水体,打包效应较弱,对675 nm处比吸收系数的影响平均仅为6%.采用多元线性回归的方法对吸收光谱进行分析,发现除叶绿素a之外的辅助色素对吸收系数的贡献主要表现在蓝绿光波段,三个航次440 nm波长处对总吸收的贡献平均分别为44%,43%和53%,其中对珠江口和广东沿岸航次的水体主要是光合类胡萝卜素的吸收贡献,而对南海北部航次的水体除了光合类胡萝卜素以外还要受到光保护类胡萝卜素的影响.由于河口、近岸和外海水体藻类粒级结构和辅助色素成分对浮游植物吸收系数的贡献有明显的差异,在南海北部水体建立比较精确的生物光学模型时,需考虑藻类粒级结构及色素成分对浮游植物吸收系数的影响.  相似文献   

Effects of winds,tides and storm surges on ocean surface waves in the Sea of Japan   总被引：1，自引：1，他引：0  

ZHAO Wei  TIAN Jiwei  LI Peiliang  HOU Yijun 《海洋学报(英文版)》2007,26(3):9-21

Ocean surface waves are strongly forced by high wind conditions associated with winter storms in the Sea of Japan. They are also modulated by tides and storm surges. The effects of the variability in surface wind forcing, tides and storm surges on the waves are investigated using a wave model, a high-resolution atmospheric mesoscale model and a hydrodynamic ocean circulation model. Five month-long wave model simulations are inducted to examine the sensitivity of ocean waves to various wind forcing fields, tides and storm surges during January 1997. Compared with observed mean wave parameters, results indicate that the high frequency variability in the surface wind filed has very great effect on wave simulation. Tides and storm surges have a significant impact on the waves in nearshores of the Tsushima-kaihyō, but not for other regions in the Sea of Japan. High spatial and temporal resolution and good quality surface wind products will be crucial for the prediction of surface waves in the JES and other marginal seas, especially near the coastal regions.  相似文献   

Distribution of the nonlinear random ocean wave period     

侯一筠  李明杰  宋贵霆  司广成  齐鹏  胡珀 《中国海洋湖沼学报》2009,27(4):919-923

Because of the intrinsic difficulty in determining distributions for wave periods, previous studies on wave period distribution models have not taken nonlinearity into account and have not performed well in terms of describing and statistically analyzing the probability density distribution of ocean waves. In this study, a statistical model of random waves is developed using Stokes wave theory of water wave dynamics. In addition, a new nonlinear probability distribution function for the wave period is presented with the parameters of spectral density width and nonlinear wave steepness, which is more reasonable as a physical mechanism. The magnitude of wave steepness determines the intensity of the nonlinear effect, while the spectral width only changes the energy distribution. The wave steepness is found to be an important parameter in terms of not only dynamics but also statistics. The value of wave steepness reflects the degree that the wave period distribution skews from the Cauchy distribution, and it also describes the variation in the distribution function, which resembles that of the wave surface elevation distribution and wave height distribution. We found that the distribution curves skew leftward and upward as the wave steepness increases. The wave period observations for the SZFII-1 buoy, made off the coast of Weihai (37°27.6′ N, 122°15.1′ E), China, are used to verify the new distribution. The coefficient of the correlation between the new distribution and the buoy data at different spectral widths (ν=0.3−0.5) is within the range of 0.968 6 to 0.991 7. In addition, the Longuet-Higgins (1975) and Sun (1988) distributions and the new distribution presented in this work are compared. The validations and comparisons indicate that the new nonlinear probability density distribution fits the buoy measurements better than the Longuet-Higgins and Sun distributions do. We believe that adoption of the new wave period distribution would improve traditional statistical wave theory.  相似文献   

太平洋赤道潜流起源的模式研究     

吕艳  王庆业 《广东海洋大学学报》2009,29(4):58-62

基于一个高分辨率准全球海洋模式HYCOM(HYbrid Coordinate Ocean Model),研究了热带西太平洋海域赤道潜流的起源。结果表明:赤道潜流在大约130°E处开始,流核位于225 m、2°N附近,最大流速超过15 cm/s,体积输运约1.6×106 m3/s,其水源来自棉兰老海流;在东部140°E断面,赤道潜流的北部主要是由棉兰老海流提供(9.7×106 m3/s),其南部主要是来自新几内亚沿岸潜流(9.1×106 m3/s)。  相似文献   

Radar cross section analysis of marine targets using a combining method of physical optics/geometric optics and a Monte-Carlo simulation     

Kookhyun Kim  Jin-Hyeong Kim 《Ocean Engineering》2009,36(11):821-830

In this paper, the radar cross section of flat plates on ocean surfaces is statistically investigated. A combining method of physical optics and geometric optics is applied to establish an effective backscattering analysis procedure. This method is a high-frequency analysis method originally derived from a simplified Stratton-Chu integral equation, assuming that the radar is far away from the target so that Kirchhoff approximation is valid. A Monte-Carlo simulation method is adopted to statistically analyze the effects of undulated ocean surfaces. The ocean surfaces are randomly generated by Pierson-Moskowitz ocean wave spectrum and a directional distribution function. Numerical investigations are carried out for flat plates, with the same height and width but with different inclined angles, on ocean surfaces of various significant wave heights.  相似文献   

Adaptation of the vertical resolution in the mixed layer for HYCOM   总被引：1，自引：0，他引：1  

Ccile Renaudie  Rmy Baraille  Yves Morel  Gwenaëlle Hello  Herv Giordani 《Ocean Modelling》2009,30(2-3):178-189

This paper focuses on the dynamics of the mixed layer. When the mixed layer depth increases, the vertical discretisation eventually becomes too sparse at the bottom of this layer to accurately resolve its evolution and strong numerical errors can appear. This is linked to the fact that the vertical resolution is concentrated in the upper part of the ocean and does not adapt to the deepening of the mixed layer.Knowing that the HYbrid Coordinate Ocean Model (HYCOM) is able to modify the distribution of the vertical levels, we suggest in this paper a method to adapt the resolution to the mixed layer extension. This method is tested in 1-D configurations for two academic atmospheric forcing conditions (strong convection and wind-mixing) and a realistic forcing extending over one year, with seasonal restratification following strong winter convection. The new method improves the results in all cases, and in particular when the mixed layer reaches deep layers.  相似文献