星站差分与PPP技术在深远海调查中的位置服务精度分析

利用在全球不同海域的船载GNSS进出港数据,以事后动态处理技术(PPK)的坐标计算值为评价基准,分析了Veripos星站差分系统和事后动态精密单点定位技术(PPP)在不同运动状态下的位置服务精度。结果表明,Veripos与PPP在低动态下的平面与高程位置服务精度可优于6.2 cm和14.9 cm,在常规动态下平均精度优于20 cm;PPP与Veripos坐标分量平均互差小于15 cm,标准差小于23 cm,在深远海调查中PPP技术可作为星站差分系统的有效补充和特殊情况下的位置服务替代。     

深远海工程调查作业保障体系探讨

深远海海洋工程活动需要在手续齐全、批文合法的条件下开展作业,但因其面临更为复杂的环境和挑战,建立健全调查作业保障体系十分必要。文章通过分析深远海工程调查作业的类型、特点、需求等,探讨了其保障体系的内容组成,并对船舶及装备保障、组织及人员保障、远海通信保障、调查实施方案保障、质量管理和控制保障、HSE保障、应急预案保障进...     

基于过程分析方法的海洋工程项目承包风险评估

运用过程分析方法和风险评估技术,结合海洋工程项目现状,对项目承包进行风险分析。首先,运用事故树方法建立项目承包各阶段的风险事故树;然后,利用风险估计方法综合得到风险事件的评定等级;最后,给出风险控制措施。通过评估结果和建议,以降低海洋工程项目承包风险发生的可能性,减少事故损失。     

赤道印度洋中部断面东西水交换的季节变化及其区域差异

采用海洋再分析资料和实测资料研究了热带印度洋中部东西水交换特征。结果表明存在两个相互独立的过程,即北印度洋过程(4°~6°N)和赤道过程(2°S-2°N)。北印度洋过程受季风影响显著,11月至翌年3月冬季风期间表现出很强的低盐水向西输送,5-9月夏季风期间则为高盐水向东输送;由于冬季风期间的输送较强,年平均表现为低盐水向西输送。赤道过程分为表层过程和次表层过程。表层赤道过程受局地风场驱动,有明显的半年周期;4-5月和10-11月的东向流将赤道西印度洋的高盐水向东输送,其余月份相反;向东的输送较强,年平均表现为净高盐水向东输送。在次表层赤道过程没有明显的季节变化,海流全年一致向东,将海盆西部的高盐水向东输送。     

印度洋海底压强的季节和长期变化

利用2003—2015年的重力恢复和气候实验(Gravity Recovery and Climate Experiment, GRACE)卫星观测数据, 揭示了印度洋海底压强的变化特征, 并探讨了其变化机制。结果表明, 印度洋海底压强具有显著的季节变化特征, 北半球冬季在40°S以北(南), 海底压强呈负(正)异常, 夏季分布与冬季相反。印度洋区域的海底压强空间分布与Ekman输送空间分布有较好的对应关系。正压涡度方程诊断结果表明, 利用风场重构的海底压强能够较好地解释印度洋海底压强的季节和长期变化。此外, 海平面变化收支分析表明, 海底压强的变化在高纬度区域主导了海平面变化。     

融池热力学模式以及它在2010年夏季北极中央区的应用研究

A one-dimensional thermodynamic model of melt pond is established in this paper.The observation data measured in the summer of 2010 by the Chinese National Arctic Research Expedition(CHINARE-2010) are used to partially parameterize equations and to validate results of the model.About 85% of the incident solar radiation passed through the melt pond surface,and some of it was released in the form of sensible and latent heat.However,the released energy was very little(about 15%),compared to the incident solar radiation.More than 58.6% of the incident energy was absorbed by melt pond water,which caused pond-covered ice melting and variation of pond water temperature.The simulated temperature of melt pond had a diurnal variation and its value ranged between 0.0°C and 0.3°C.The melting rate of upper pond-covered ice is estimated to be around two times faster than snow-covered ice.At same time,the change of melting rate was relatively quick for pond depth less than 0.4 m,while the melting rate kept relatively constant(about 1.0 cm/d) for pond depth greater than 0.4 m.     

一种基于工作流逻辑偶的海域无人机监视监测业务流程建模方法

通过构建海域无人机监视监测业务流程形式化模型,为海域无人机监控与管理系统能够自适应可变的业务流程奠定基础。首先对比了各种业务流程建模方法的技术特点和适用场景,然后对海域无人机监视监测业务流程进行分析,提出了一种UML活动图转化为基于Petri网的工作流逻辑偶的方法,最后基于此方法对海域无人机监视监测业务流程进行建模。建模结果表明,该方法能有效地将海域无人机监视监测业务流程的分支、分叉以及汇合等流程逻辑转化为工作流逻辑偶,并且转化的结果满足良序性、良构性以及畅通性。     

东太平洋海盆430柱沉积物特征与地层

对东太平洋海盆 ４３０ 柱沉积物的组分、古生物、结构构造以及古地磁、铀系等进行研究后, 将沉积物进行分类、命名与分层, 并确定其年代。研究表明, 本柱由下至上的沉积物分别为含沸石粘土、深海粘土、硅质粘土和钙质粘土。该柱中存在 ４ 个沉积间断, 其中在 ３２５ ｃｍ附近层位有一厚约 １０ ｃｍ 的多金属结核层,此界面为中中新世至晚上新世的沉积间断,它在 Ｃ Ｃ区内普遍存在, 持续时间长, 分布范围广。反映此时南极底层流十分强盛, 对东太平洋 Ｃ Ｃ 区的沉积作用和多金属结核形成与发育产生重要的影响。     

南大洋气旋气候与变化特征

A new climatology of cyclones in the Southern Ocean is generated by applying an automated cyclone detection and tracking algorithm(developed by Hodges at the Reading University) for an improved and relatively highresolution European Centre for Medium-Range Weather Forecasts atmospheric reanalysis during 1979–2013.A validation shows that identified cyclone tracks are in good agreement with a available analyzed cyclone product.The climatological characteristics of the Southern Ocean cyclones are then analyzed,including track,number,density,intensity,deepening rate and explosive events.An analysis shows that the number of cyclones in the Southern Ocean has increased for 1979–2013,but only statistically significant in summer.Coincident with the circumpolar trough,a single high-density band of cyclones is observed in 55°–67°S,and cyclone density has generally increased in north of this band for 1979–2013,except summer.The intensity of up to 70% cyclones in the Southern Ocean is less than 980 h Pa,and only a few cyclones with pressure less than 920 h Pa are detected for1979–2013.Further analysis shows that a high frequency of explosive cyclones is located in the band of 45°–55°S,and the Atlantic Ocean sector has much higher frequent occurrence of the explosive cyclones than that in the Pacific Ocean sector.Additionally,the relationship between cyclone activities in the Southern Ocean and the Southern Annular Mode is discussed.     

印度洋深海沉积物样品纯培养细菌的分离鉴定

为探索印度洋深海沉积物中纯培养细菌的多样性,本文对采自印度洋12个沉积物样品进行细菌纯培养分离,共获得343株细菌。所有细菌采用16S rRNA 基因进行比对分析,鉴定为4个门：厚壁菌门（Firmicutes）、变形菌门（Proteobacteria）、放线菌门（Actinobacteria）和拟杆菌门（Bacteroidetes）,5个纲,13个目,26个科,39个属下的121个种。分离出的优势类群为链霉菌属（Streptomyces,分离率为16.53%）和芽孢杆菌属（Bacillus,分离率为8.26%）,其中可能有12个潜在的新分类单元。研究结果表明,印度洋深海沉积环境中纯培养细菌资源丰富,潜在新物种较多;其次,分离培养方法与从海洋沉积物中获得的细菌物种多样性直接相关。     

中西太平洋镰状真鲨的生物学信息初步研究

镰状真鲨(Carcharhinus falciformis)是金枪鱼(Thunnus)延绳钓渔业中常见的兼捕鱼种之一,位于海洋食物链的顶端,对海洋物种多样性和生态系统的稳定性有重要意义,2017年10月1日作为濒危物种被正式列入濒危野生动植物种国际贸易公约附录Ⅱ中。作者根据中国金枪鱼渔业科学观察员在中西太平洋海域(7°S~9°N,149°E~150°W)采集的1 150尾镰状真鲨样本,对其叉长、体质量、繁殖和摄食等生物学信息进行初步研究与分析。结果表明:雌、雄镰状真鲨的优势叉长范围分别为80~180 cm和60~150 cm,雌性叉长均值显著大于雄性;雌、雄的叉长和体质量关系无显著性差异(ANCOVA,P0.05),叉长和体质量的幂函数关系为:W_R=9×10–6×L_F~(2.9712);雌、雄性比符合1︰1比例;镰状真鲨的鳍脚长度与叉长呈显著正相关性,其线性关系为L_C=0.1492×L_F–6.5;镰状真鲨的怀仔数为4~15尾,平均怀仔数为8尾,子宫内雌雄胚胎长度范围为24~56 cm;摄食等级以空胃率为主,其次为1级,分别为51.77%、35.07%。     

Upper Ocean Four-Dimensional Variational Data Assimilation in the Arabian Sea and Bay of Bengal

A regional ocean circulation model with four-dimensional variational data assimilation scheme is configured to study the ocean state of the Indian Ocean region (65°E–95°E; 5°N–20°N) covering the Arabian Sea (AS) and Bay of Bengal (BoB). The state estimation setup uses 10 km horizontal resolution and 5 m vertical resolution in the upper ocean. The in-situ temperature and salinity, satellite-derived observations of sea surface height, and blended (in-situ and satellite-derived) observations of sea surface temperature alongwith their associated uncertainties are used for data assimilation with the regionally configured ocean model. The ocean state estimation is carried out for 61 days (1 June to 31 July 2013). The assimilated fields are closer to observations compared to other global state estimates. The mixed layer depth (MLD) of the region shows deepening during the period of assimilation with AS showing higher MLD compared to the BoB. An empirical forecast equation is derived for the prediction of MLD using the air–sea forcing variables as predictors. The surface and sub-surface (50 m) heat and salt budget tendencies of the region are also investigated. It is found that at the sub-surface, only the advection and diffusion temperature and salt tendencies are important.