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1.
The Localized Weighted Ensemble Kalman Filter(LWEnKF) is a new nonlinear/non-Gaussian data assimilation(DA) method that can effectively alleviate the filter degradation problem faced by particle filtering, and it has great prospects for applications in geophysical models. In terms of operational applications, along-track sea surface height(AT-SSH), swath sea surface temperature(S-SST) and in-situ temperature and salinity(T/S) profiles are assimilated using the LWEnKF in the northern South China ...  相似文献   

2.
Offline bias correction of numerical marine forecast products is an effective post-processing means to improve forecast accuracy. Two offline bias correction methods for sea surface temperature(SST) forecasts have been developed in this study: a backpropagation neural network(BPNN) algorithm, and a hybrid algorithm of empirical orthogonal function(EOF) analysis and BPNN(named EOF-BPNN). The performances of these two methods are validated using bias correction experiments implemented in the South...  相似文献   

3.
夏威夷历史海啸记录包含远距离和当地产生的海啸,由这些事件引起的人员伤亡和对建筑、环境造成的破坏与损失是惊人的,但是在近来才有一些对历史海啸沉积事件的综合性的研究.夏威夷多岩石的海岸线的演变主要是海啸和风暴的贡献,然而区分风暴和海啸是很难的,特别是相关的小的历史海啸事件.因此夏威夷海啸的研究往往关注于大的古海啸沉积事件.研究表明远距离产生的事件,如1946年阿留申海啸对瓦胡岛岩石岸线的演变具有重要影响.活火山也有助于岩石岸线的形成,且容易引发当地海啸.现代活动的Kilauea火山南侧海域的逐步沉降并没有引起太平洋范围内的破坏性的大海啸,但引发了局部一系列重要的海啸事件,这些事件的周期被估计认为是200年.  相似文献   

4.
Using sea surface salinity(SSS)observation from the soil moisture active passive(SMAP)mission,we analyzed the spatial distribution and seasonal variation of SSS around Changjiang River(Yangtze River)Estuary for the period of September 2015 to August 2018.First,we found that the SSS from SMAP is more accurate than soil moisture and ocean salinity(SMOS)mission observation when comparing with the in situ observations.Then,the SSS signature of the Changjiang River freshwater was analyzed using SMAP data and the river discharge data from the Datong hydrological station.The results show that the SSS around the Changjiang River Estuary is significantly lower than that of the open ocean,and shows significant seasonal variation.The minimum value of SSS appears in July and maximum SSS in December.The root mean square difference of daily SSS between SMAP observation and in situ observation is around 3 in both summer and winter,which is much lower than the annual range of SSS variation.In summer,the diffusion direction of the Changjiang River freshwater depicted by SSS from SMAP is consistent with the path of freshwater from in situ observation,suggesting that SMAP observation may be used in coastal seas in monitoring the diffusion and advection of freshwater discharge.  相似文献   

5.
我国是管理海域辽阔,海岸线漫长,资源丰富的海洋大国。大力发展海洋事业,事关国家的长治久安和经济社会的可持续发展。加强对海洋的观测和了解,准确预报海洋灾害,合理开发利用海洋资源,努力保护海洋生态环境,有效维护国家海洋主权与权益,是广大海洋工作者和海洋管理部门的神圣使命和战略任务。国家海洋局从建局以来,就一直积极发展海洋科学技术,着力强化海洋观测系统建设,不断提高对海洋的持久观测能力,为海洋事业实现跨越式发展提供了强有力的支撑。  相似文献   

6.
7.
一、本刊为海洋与湖沼科学的综合性学术刊物。内容包括:1.海洋与湖沼科学研究的论文、调查及实验报告;2.海洋与湖沼科学的综合评述、重要书刊和论文的评介;3.国内外海洋与湖沼科学的先进经验及学术动态。二、投稿须知1.来稿的图、表及说明要清楚、准确,置于文中相应位置。论文要求文字、语法符合汉语规范,标点使用要恰当。电子稿书写请按宋体5号字、1.5倍行距。文中使用照片的,请寄冲  相似文献   

8.
2011年9月17日是国际海岸清洁日。由辽宁省盘锦市保护斑海豹志愿者协会发起,盘锦市180多名环保志愿者来到辽河入海口的斑海豹栖息地三道沟和六道沟海岸,捡拾海边不可降解的白色垃圾。这是盘锦市第一次组织和参与国际海岸清洁日活动。这次活动早在8月就在盘锦市保护斑海豹志愿者协会论坛上发帖通知,并在《辽河晚报》发布了征召志愿者的公告。协会会员和广大志愿者积极报名参加,上至70多岁的老人,下至7、8岁的孩童,有的是一家三口自驾车参加活动。17日是个周末,  相似文献   

9.
科技短消息     
腰围增大,大脑萎缩?与相对较瘦的老年人相比,肥胖老年人的大脑认知区域较小,这使得他们的大脑年龄至少比实际年龄老了16岁。从前有研究表明,中年肥胖会增大日后患老年痴呆的风险,而老年痴呆通常伴随着大脑萎缩。美国加州大学的科学家们选择了94  相似文献   

10.
Anaerobic, aerobic, and facultative bacteria are all present in corrosive environments. However, as previous studies to address corrosion in the marine environment have largely focused on anaerobic bacteria, limited attention has been paid to the composition and function of aerobic and facultative bacteria in this process. For analysis in this study, ten samples were collected from rust layers on steel plates that had been immersed in seawater for diff erent periods (i.e., six months and eight years) at Sanya and Xiamen, China. The cultivable aerobic bacterial community structure as well as the number of sulfate-reducing bacteria (SRB) were analyzed in both cases, while the proportion of facultative SRB among the isolated aerobic bacteria in each sample was also evaluated using a novel approach. Bacterial abundance results show that the proportions are related to sea location and immersion time;abundances of culturable aerobic bacteria (CAB) and SRB from Sanya were greater in most corrosion samples than those from Xiamen, and abundances of both bacterial groups were greater in samples immersed for six months than for eight years. A total of 213 isolates were obtained from all samples in terms of CAB community composition, and a phylogenetic analysis revealed that the taxa comprised four phyla and 31 genera. Bacterial species composition is related to marine location;the results show that Firmicutes and Proteobacteria were the dominant phyla, accounting for 98.13% of the total, while Bacillus and Vibrio were the dominant genera, accounting for 53.06% of the total. An additional sixfacultative SRB strains were also screened from the isolates obtained and were found to encompass the genus Vibrio (four strains), Staphylococcus (one strain), and Photobacterium (one strain). It is noteworthy that mentions of Photobacterium species have so far been absent from the literature, both in terms of its membership of the SRB group and its relationship to corrosion.  相似文献   

11.
利用PSR模型中压力、状态、响应相互作用的关系阐述围填海开发活动对海洋资源的影响,基于压力、状态、响应子系统确定并标准化处理了影响评价指标,根据判断矩阵分析结果赋值了指标权重,构建了围填海开发活动对海洋资源影响的评价体系,应用该评价体系进行了福建省福清湾及海坛峡海域围填海开发活动对其海洋资源的影响分析,评价结果表明福清湾及海坛峡海域围填海开发活动对其海洋资源的影响较小.  相似文献   

12.
利用PSR模型中压力、状态、响应相互作用的关系阐述围填海开发活动对海洋资源的影响,基于压力、状态、响应子系统确定并标准化处理了影响评价指标,根据判断矩阵分析结果赋值了指标权重,构建了围填海开发活动对海洋资源影响的评价体系,应用该评价体系进行了福建省福清湾及海坛峡海域围填海开发活动对其海洋资源的影响分析,评价结果表明福清湾及海坛峡海域围填海开发活动对其海洋资源的影响较小。  相似文献   

13.
在介绍了WebGIS和地学虚拟环境技术特征的基础上,研究了WebGIS技术在地学虚拟环境中的应用。从系统结构、用户界面、数据模型等三个方面,对WebGIs技术用于地学虚拟环境的深层次系统框架进行了研讨,并对WebGIS技术与地学虚拟环境技术进行结合的实际过程进行了说明。  相似文献   

14.
主要基于船体、航速、续航能力、作业海况、搭载仪器、操作方式以及主要用途等方面,详细阐述了国内外测量无人艇的技术参数,分析了国内无人艇的不足和重点攻克的技术,以及螺旋桨、喷泵两种推进方式的优缺点;分析了测量无人艇艇型、自动控制、载体总体设计及集成、环境感知、通信等关键技术及实现途径;指出测量一体化、智能化水平的提升、水陆一体化测量技术、组网测绘为测量无人艇未来的发展方向。  相似文献   

15.
海洋磁力异常逼近方法研究   总被引:7,自引:0,他引:7  
通过对常用的数值逼近方法的分析和研究,针对海洋磁力测量的特点,仿真计算分析了移动曲面法、Hardy多面函数法、Shepard法和Kriging法在不同情况下的插值精度。同时,给出了一个实例来计算分析四种逼近方法插值精度。仿真与实例计算结果表明,已知点的分布情况及磁异常变化情况不同时,四种逼近方法的插值精度是不同的。针对不同的情况,本文总结出了适合于海洋磁力异常逼近的方法。  相似文献   

16.
海水养殖对沿岸生态环境影响的研究进展   总被引:2,自引:1,他引:1  
综述国际上海水养殖对沿岸环境影响的研究进展 ,并结合中国实际探讨减少养殖污染和海水养殖业可持续发展的途径。海水养殖主要通过有机物和营养物的排放、化学药物的使用、养殖动物的逃逸、红树林的破坏等途径对沿岸生态环境产生负面影响。为减小这一影响 ,认为应采取提高人工饲料的质量、单一养殖系统结构优化和复合养殖系统的结构优化、处理养殖排放水、海岸带综合治理等措施。  相似文献   

17.
福建海水养殖鱼类本尼登虫病研究   总被引:1,自引:0,他引:1  
对福建海域网箱养殖鱼类本尼登虫病(Benedeniasis)进行了研究,调查发现6种本尼登虫病原,完成新本尼登虫季节感染动态和生活史的研究。研究结果表明,鱼群本尼登虫自然感染率平均52.14%,最高感染率达100%。考察结果说明福建海域网箱养殖鱼类本尼登虫的感染和流行与渔区海水温度和降雨量关系最大,福建海域在一年中的6月至10月份是网箱养殖鱼类本尼登虫病感染和流行的高峰季节。  相似文献   

18.
为了解决海床基在淤泥质海底的吸附力问题,利用ANSYS软件,采用接触分析、三维十节点实体单元以及Drucker-Prager模型模拟淤泥结构,分析了海床基在淤泥质海底的吸附力大小,然后与经验公式比较,证明了ANSYS对海床基吸附力分析的可行性;海床基在不同工况下的吸附力模拟对海床基的回收方式及结构优化等方面提供了一定的指导。  相似文献   

19.
基于数据库的地形图制图研究   总被引:1,自引:0,他引:1  
GIS数据和制图数据之间的差异是基于GIS数据库实现地图制图输出的难点。分析了当前基础地理信息数据建库的情况及其适用于基本比例尺制图的特点,充分利用了ArcGIS提供的地图表现功能,探讨了ArcGIS环境下基于Geodatabase数据库实现基本比例尺地形图制图的方法,并采用ArcObjects作为二次开发的平台,设计开发了基于GIS数据库的基本比例尺地形图制图模块。  相似文献   

20.
In respect of an offshore berthing pillar, the test study result of current force acting on mooring ships is described in this paper. Empirical and semi-empirical relationships of current force coefficient are given according to the angle between the flow direction and the ship's longitudinal axis, which are coincident with the result of theoretical analysis.  相似文献   

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