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961.
通过MACROMEDIA STUDIO MX的FLASH MX工具软件的分析和研究,针对海洋领域的相关信息数据的特性,根据相关的海洋监测预报业务的专业需求,在搭建网站平台的同时,探讨了如何深层次地对FLASH MX开发功能的挖掘,在海洋信息应用领域率先提出了在海洋相关业务网站中建立RIA的理念和FLASHWEB的应用案例,继而在对FLASH应用前景的分析研究中也充分表述FLASHWEB在海洋领域的商业利用价值。 相似文献
962.
963.
全球海洋模式对CFC-11分布的初步模拟研究 总被引:5,自引:2,他引:3
使用中国科学院大气物理研究所(IAP)三十层全球海洋模式(L30T63)研究了CFC-11在全球海洋中的吸收和分布,初步讨论了决定其分布特征的可能因素.该模式采用自由表面结构和Gent-McWilliams中尺度示踪物参数化方案.通过对控制试验得到的CFC-11模拟结果分析可知,CFC-11海表浓度受温度影响显著,其分布形状大致与温度相似,但梯度相反.通量的分布受温度影响很大,且表现出很明显的季节变化特征,如不饱和区一般出现在冬季海区的中层水形成处或者强对流混合存在的区域.另外,对CFC-11的模拟结果与三个大洋的五个断面航测资料做了对比,发现模拟结果与观测资料吻合较好,能比较清楚地反映CFC-11输送与等密度面垂直分布以及环流场的密切关系,如在南大洋50°S以北至35°S以南等密度面的向下加深区是CFC-11的主要贮存区等.与大多数前人的工作相比,该模拟结果较好地反映了CFC-11在南大洋的分布特征.从这些反映出该模式对于大洋十年尺度物质交换与海洋内部输送的模拟是比较准确的. 相似文献
964.
综述了海洋测高卫星激光定轨的发展近况,论述了我国将发射的HY-2海洋二号卫星实现激光定轨的技术途径及其达到厘米级精度定轨的可能性。 相似文献
965.
966.
星载雷达波谱仪反演海浪谱的精度研究 总被引:1,自引:1,他引:0
介绍了星载雷达波谱仪的观测原理及误差分析模型,并在Hauser等提出的SWI M(sea wave investigation and monitoring by satellite)的基础上分析了波谱仪反演海浪谱的波长分辨率和角度分辨率。为了减小反演调制谱的波动,在数据处理过程中时域和波数域相邻单元的平均个数分别为10和8个。系统在不同的模式下工作,为了获取20°的角度分辨率,对调制谱平均次数分别取3次(模式1)、7次(模式2)、10次(模式3)。使用解析法和仿真法分析了SWI M工作在模式2时海浪谱观测的能量误差,两种方法的结果一致。对于给定的海浪条件,能量误差小于20%。 相似文献
967.
Waters along China coast are very turbid with high concentrations of suspended sediment nearly all the time,especially at the Hangzhou Bay,the Changjiang (Yangtze) River Estuary and the shoal along Jiangsu Province.In these turbid and optically complex waters,the standard MODIS ocean color products tend to have invalid values.Because the water-leaving radiances in the near-infrared (NIR) are significant resulting from the strong scattering of suspended particles,the standard MODIS atmospheric correction algorithm often gets no results or produces significant errors.And because of the complex water optical properties,the OC3 model used in the standard MODIS data processing tends to get extremely high chlorophyll-a (Chl-a) concentrations.In this paper,we present an atmospheric correction approach using MODIS short wave infrared (SWIR) bands based on the fact that water-leaving radiances are negligible in the SWIR region because of the extreme strong absorption of water even in turbid waters.A regional Chl-a concentration estimation model is also constructed for MODIS from in situ data.These algorithms are applied to MODIS Aqua data processing in the China coastal regions.In situ data collected in the Yellow Sea and the East China Sea in spring and autumn,2003 are used to validate the performance.Reasonably good results have been obtained.It is noted that water-leaving reflectance in the NIR bands are significant in waters along the China coast with high sediment loadings.The satellite derived and in-situ reflectance spectra can match in the turbid waters along China coast,and there is relatively good linear relationship between satellite derived and in-situ reflectance.The RMSE value of Rrs(λ) is 0.0031 sr ?1 for all the nine ocean color bands (412 to 869 nm).The satellite-derived Chl-a value is in the reasonable range and the root mean square percentage difference is 46.1%. 相似文献
968.
Laura McFarlane Tranquilla April Hedd Chantelle Burke William A. Montevecchi Paul M. Regular Gregory J. Robertson Leslie Ann Stapleton Sabina I. Wilhelm David A. Fifield Alejandro D. Buren 《Estuarine, Coastal and Shelf Science》2010
Ocean climate change is having profound biological effects in polar regions. Such change can also have far-reaching downstream effects in sub-polar regions. This study documents an environmental relationship between High Arctic sea ice changes and mortality events of marine birds in Low Arctic coastal regions. During April 2007 and March 2009, hundreds of beached seabird carcasses and moribund seabirds were found along the east and northeast coasts of Newfoundland, Canada. These seabird “wrecks” (i.e. dead birds on beaches) coincided with a period of strong, persistent onshore winds and heavily-accumulated sea ice that blocked bays and trapped seabirds near beaches. Ninety-two percent of wreck seabirds were Thick-billed Murres (Uria lomvia). Body condition and demographic patterns of wreck murres were compared to Thick-billed Murres shot in the Newfoundland murre hunt. Average body and pectoral masses of wreck carcasses were 34% and 40% lighter (respectively) than shot murres, indicating that wreck birds had starved. The acute nature of each wreck suggested that starvation and associated hypothermia occurred within 2–3 days. In 2007, first-winter murres (77%) dominated the wreck. In 2009, there were more adults (78%), mostly females (66%). These results suggest that spatial and temporal segregation in ages and sexes can play a role in differential survival when stochastic weather conditions affect discrete areas where these groups aggregate. In wreck years, southward movement of Arctic sea ice to Low Arctic latitudes was later and blocked bays longer than in most other years. These inshore conditions corresponded with recent climate-driven changes in High Arctic ice break-up and ice extent; coupled with local weather conditions, these ice conditions appeared to be the key environmental features that precipitated the ice-associated seabird wrecks in the Low Arctic region. 相似文献
969.
970.
应用1个改进的含有动边界技术的河口海岸动力模型模拟了泉州湾洛阳江口的潮汐潮流.结果表明M2分潮在洛阳江口的主河道占据主导地位,但是随着潮波向浅滩的传播,其能量通过海底摩擦作用或非线性耗散作用逐渐转移至浅水潮,其中尤以M4分潮的增长最为显著.浅水分潮的增长又会引起天文分潮涨、落潮流的不对称性.进一步检验洛阳江口的潮流历时(月平均的涨、落潮流历时分别为6 h 1 min 30 s和6 h 19 min 58 s)和潮汐余流特征发现:该水域以涨潮流为主,由此产生的涨、落潮流的不对称可能有利于潮滩的进一步扩展. 相似文献