首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 62 毫秒
1.
潮流场永久预报方法及应用   总被引:3,自引:0,他引:3  
本方法的特点是以一个假想的引潮天体来代替月球和太阳的引潮作用.用该引潮天体星下点处的引潮力作为预报指标,对海区的整个潮流场进行计算与预报。在本方法中,把潮流场分为两种类型:把周日不等最弱的流场,称为Ⅰ型流场;把周日不等最强烈的流场,称为Ⅱ型流场。介于这两者之间的流场,则为过渡性的流场,流场的周期是与星下点处引潮力的周期相同。本方法已运用于渤海和北黄海.提供了该海区的表层流场永久预报图,并成功地进行过多次预报。  相似文献   

2.
台风周围的天气系统和大气环流是瞬息万变的,特别是在台风穿过台湾岛时,受台湾岛地形的影响,其强度和移动路径常常会发生改变,易导致风暴潮预报的失败。本文基于"台湾海峡海洋环境立体实时监测系统"实时监测海上水文、气象要素的变化,准确分析判断了台风"凤凰"的移动路径,提高了临近台风风暴潮预警报的准确度,为地方决策部门安排重点设防风暴潮灾害提供了有力支持。  相似文献   

3.
周期外推方法在海水水温预报中的应用   总被引:1,自引:0,他引:1  
针对海水温度的周期性变化,利用周期外推方法进行海水水温预报,并用平稳过程对周期变化以外的部分进行拟合,最后得到预报值。与实际观测资料比较,检验了预报的结果。  相似文献   

4.
台风“麦沙”登陆后减弱为热带风暴并从山东半岛西部进入渤海,造成8~9级阵风、10级的大风天气,天津沿海潮位超过警戒潮位46cm,海水漫过堤岸,形成风暴潮灾害。针对此次台风风暴潮,预报人员运用经验预报方法(相似型经验预报、统计模型预报)和数值模式(FBM模式)产品等多种手段,对天津沿海可能出现的潮位极值进行了试验预报。通过将上述几种方法实际运用于此次台风风暴潮预报,加深了对各种预报方法实用性和局限性的认识,对渤海台风风暴潮有了更清晰的了解,对改进各种方法,更好地释用数值预报产品起着积极的意义。  相似文献   

5.
利用山东122个国家级地面气象观测站2017—2021年中1—3月和11—12月“24 h降雪量p≥10.0 mm”的暴雪实况资料,采用二分类法、邻域空间检验法(以下简称“邻域法”)、时间偏移法和量级模糊法等4种方法对山东暴雪预报进行检验与对比。结果表明:(1)山东暴雪具有明显的时空分布特征,暴雪主要出现在半岛北部地区,鲁东南和半岛南部产生暴雪的概率最小;暴雪出现次数的年际变化和月际变化较大,最多年份出现98次,最少年份仅有5次,2月是高发月,占全年暴雪总次数的38.5%。(2)现行业务中应用最广泛的二分类法检验的预报命中率较低,其中24 h预报命中率仅为12.08%,主要原因是该方法受到空间、时间和量级的多重影响,不能精细准确地反映预报能力。(3)邻域法、时间偏移法和量级模糊法对24 h的暴雪预报命中率分别为14.40%、14.69%和30.05%;相较于二分类法,这3种检验方法的预报命中率均有较大幅度提高,空报率和漏报率均有较大幅度下降。(4)融合邻域法、时间偏移法和量级模糊法的综合检验法,能从空间、时间和量级3个维度区分出预报差异,检验结果更加精细准确,有利于引导预报员放下“检验评分低”的思想包袱,做出更加科学客观的预报,进一步提升预报服务效果。  相似文献   

6.
耗散结构热力学理论在一次海上大风预报中的应用   总被引:1,自引:0,他引:1  
1988年3月13~15日在中国东部海域发生了一次历史上罕见的大风天气过程。本文首先对这次过程作了天气形势分析,然后分析了耗散结构热力学理论在大气中的表现形成,并给出了超熵产生的平流诊断方程,计算结果指出850hPa层超熵产生的负值区可提前12~24小时预示大风的发生。  相似文献   

7.
复经验正交函数方法在黄海水温预报中的应用   总被引:3,自引:0,他引:3  
本文介绍了复经验正交函数(CEOF)方法,并首次将其应用于黄海的水温预报,同时与依据同样资料采用经验正交函数(EOF)方法所作的预报进行了对比.比较可知,在黄海表层水温预报中,应用复经验正交函数方法所作的预报,其精度较应用经验正交函数方法提高0.20℃左右,底层预报精度相当.  相似文献   

8.
相空间反演方法在表层水温预报中的应用   总被引:4,自引:1,他引:4  
利用相空间理论及方法对渤、黄、东海共4个站位近十几年的旬平均SST进行分析。结果表明:表层水温具有混饨特性,其吸引子关联维数平均约为1.23、嵌入相空间维数为6(渤、黄海)和7(东海178号站位)、二阶Renyi熵平均约为3.7×10-4(1/d)及平均可预报时间尺度平均为27个点;基于以上分析结果运用相空间反演方法建立了旬平均SST的反演模型,并且在试预报的前5旬的最大相对误差约为4.2%。  相似文献   

9.
汪一航 《台湾海峡》2002,21(2):239-242
本文把灰色系统灾变预报方法应用到风暴潮预报中,对逐年最大风暴潮增水资料确定一个阈值ξ,对于年最大风暴潮位资料大于阈值ξ的年份组成一个序列,用一阶线性模型GM(1,1)预报风暴潮灾的出现年份,结果表明:用GM(1,1)模型可较好地预报风暴潮灾的出现年份。  相似文献   

10.
张建华 《海洋预报》2004,21(1):85-90
概率统计方法被引用到水文气象预报中来,至今已有五十余年。到60年代后期,统计预报已成为要素预报的重要手段,尤其是70年代以后“模式输出统计预报”在预报业务中使用以来,使统计预报出现了新的局面。现在水文、天气预报的概率统计方法已  相似文献   

11.
近年海上事故调查结果表明很多海难事件都与畸形波袭击有关.随着我国经济进步,海上经济和军事活动越来越频繁,畸形波对上述海事活动具有严重威胁并可能造成重大人员和财产损失.现有的数值或经验海浪预报方法不能有效地预报这种灾害性海浪,亟需开发一种可靠的畸形波预报方法,这是海浪研究中面临的新课题.本文将对畸形波的实验和理论研究现状...  相似文献   

12.
Application of the HY-1 satellite to sea ice monitoring and forecasting   总被引:1,自引:2,他引:1  
The HY-1A satellite is the first oceanic satellite of China. During the winter of 2002~2003, the data of the HY-1A were applied to the sea ice monitoring and forecasting for the Bohai Sea of China for the first time. The sea ice retrieval system of the HY-1A has been constructed. It receives 1B data from the satellite, outputs sea ice images and provides digital products of ice concentration, ice thickness and ice edge, which can be used as important information for sea ice monitoring and the initial fields of the numeric sea ice forecast and as one of the reference data for the sea ice forecasting verification. The sea ice retrieval system of the satellite is described, including its processes, methods and parameters. The retrieving results and their application to the sea ice monitoring and forecasting for the Bohai Sea are also discussed.  相似文献   

13.
Application of the HY-1 satellite to sea ice monitoring and forecasting   总被引:2,自引:2,他引:2  
The HY-1A satellite is the first oceanic satellite of China. During the winter of 2002-2003, the data of the HY-1A were applied to the sea ice monitoring and forecasting for the Bohai Sea of China for the fhst time. The sea ice retrieval system of the HY-1A has been constructed. It receives 1B data from the satellite, outputs sea ice images and provides digital products of ice concentration, ice thickness and ice edge, which can be used as important information for sea ice monitoring and the initial fields of the numeric sea ice forecast and as one of the reference data for the sea ice forecasting verification. The sea ice retrieval system of the satellite is described, including its processes, methods and parameters. The retrieving results and their application to the sea ice monitoring and forecasting for the Bohai Sea are also discussed.  相似文献   

14.
“海洋1号”卫星在海冰监测和预报中的应用   总被引:7,自引:3,他引:7  
“海洋1号A”卫星是我国发射的第一颗海洋卫星.2002~2003年冬季,该卫星首次应用于我国渤海海冰监测和预报.建立了从卫星1B级数据开始的海冰反演系统,提供海冰遥感图像和海冰密集度、冰厚与冰外缘线数值产品,作为渤海海冰监测和海冰数值预报初始场的重要信息来源,以及海冰预报质量检验的参考依据之一.介绍所发展的“海洋1号A”卫星海冰反演系统的流程、算法和反演参数,海冰反演结果,及其在渤海海冰监测和预报中的应用.  相似文献   

15.
海温是认知和研究大气、海洋物理性质和演变规律的重要海洋环境动力要素之一,也是海洋预报组成中不可或缺的组成部分,对海温的分布及演变规律进行研究对海洋经济、环保和国防安全具有重要的意义.本文提出了一种基于相似系数的海温统计预报方法,利用数理统计分析方法,构建基于相似系数的统计预报模型来实现海温的单点时间序列预报.在南海海域...  相似文献   

16.
Application of artificial neural networks in typhoon surge forecasting   总被引:1,自引:0,他引:1  
A typhoon-surge forecasting model was developed with a back-propagation neural network (BPN) in the present paper. The typhoon's characteristics, local meteorological conditions and typhoon surges at a considered tidal station at time t−1 and t were used as input data of the model to forecast typhoon surges at the following time. For the selection of a better forecasting model, four models (Models A–D) were tested and compared under the different composition of the above-mentioned input factors. A general evaluation index that is a composition of four performance indexes was proposed to evaluate the model's overall performance. The result of typhoon-surge forecasting was classified into five grades: A (excellent), B (good), C (fair), D (poor) and E (bad), according to the value of the general evaluation index. Sixteen typhoon events and their corresponding typhoon surges and local meteorological conditions at Ken–fang Tidal Station in the coast of north-eastern Taiwan between 1993 and 2000 were collected, 12 of them were used in model's calibration while the other four were used in model's verification. The analysis of typhoon-surge forecasting results at Ken–fang tidal station show that the Model D composing 18 input factors has better performance, and that it is a suitable BPN-based model in typhoon-surge forecasting. The Model D was also applied to typhoon-surge forecasting at Cheng-kung Tidal Station in south-eastern coast of Taiwan and at Tung-shih Tidal Station in the coast of south-western Taiwan. Results show that the application of Model D in typhoon-surge forecasting at Cheng-kung Tidal Station has better performance than that at Tung-shih Tidal Station.  相似文献   

17.
张莉  罗鹏 《海洋科学》2009,33(10):59-62
为了准确地研判日本珍珠产业发展势态,科学地确立中国珍珠产业发展目标,有效地制定中国珍珠产业发展政策,采用EVIEWS5.0软件构建了指数平滑模型,并对日本2008~2015年的珍珠产量进行了预测,预测结果显示日本的珍珠产量持续下降,到2015年日本的珍珠产量达到12.35 t.  相似文献   

18.
In this study,an operational forecasting system of sea dike risk in the southern Zhejiang Province,South China was developed based on a coupled storm-surge and wave model.This forecasting system is important because of the high cost of storm-surge damage and the need for rapid emergency planning.A comparison with astronomical tides in 2016 and the validation of storm surges and high water marks of 20 typhoons verified that the forecast system has a good simulation ability.The system can forecast relatively realistic water levels and wave heights as shown under the parametric atmospheric forces simulated in a case study;the sea dikes in credible high risk were mainly located in the estuaries,rivers,and around the islands in the southern Zhejiang.Therefore,the forecast system is applicable in the southern Zhejiang with a support to the effective prevention from typhoon storm-surge damage.  相似文献   

19.
逐步回归分析在渤海海冰等级预报中的应用   总被引:1,自引:0,他引:1  
根据1951—2013年渤海海冰等级资料,利用最大熵谱法分析了渤海海冰等级的周期,结果表明渤海海冰具有明显的年际和年代际变化特征,其主要周期为2—7年和11年。相关分析及逐步回归分析表明:渤海海冰的年际变化与西太平洋副高面积及北界指数、太平洋副高面积指数、亚洲区极涡面积指数以及南方涛动指数都有显著的相关关系。利用逐步回归分析方法建立的海冰预报模型经过拟合和试预报都得到了很好的结果,具有较高的可信度。  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