Impact of sea spray on upper ocean temperature during typhoon passage: simulation with a 1-D turbulent model

At the interface between the lower atmosphere and sea surface, sea spray might significantly influence air-sea heat fluxes and subsequently, modulate upper ocean temperature during a typhoon passage. The effects of sea spray were introduced into the parameterization of sea surface roughness in a 1-D turbulent model, to investigate the effects of sea spray on upper ocean temperature in the Kuroshio Extension area, for the cases of two real typhoons from 2006, Yagi and Soulik. Model output was compared with data from the Kuroshio Extension Observatory (KEO), and Reynolds and AMSRE satellite remote sensing sea surface temperatures. The results indicate drag coefficients that include the spray effect are closer to observations than those without, and that sea spray can enhance the heat fluxes (especially latent heat flux) considerably during a typhoon passage. Consequently, the model results with heat fluxes enhanced by sea spray simulate better the cooling process of the SST and upper-layer temperature profiles. Additionally, results from the simulation of the passage of typhoon Soulik (that passed KEO quickly), which included the sea spray effect, were better than for the simulated passage of typhoon Yagi (that crossed KEO slowly). These promising 1-D results could provide insight into the application of sea spray in general circulation models for typhoon studies.     

广西钦州湾百年来红树林演变的有机碳同位素和孢粉示踪及其影响因素

气候变化和人类活动制约下的红树林演变是一种长时间尺度效应,而沉积物则是记录这种响应的最佳档案。采用古生态学研究思路,选择有效的示踪参数是解读这一档案的有效途径。本文通过广西钦州湾红树林区1根柱状沉积物中有机碳同位素(δ13C)、C/N分析和孢粉鉴定,以沉积物中的红树林源有机碳贡献和红树植物孢粉组合为示踪参数,在210Pb年龄框架构建的基础上,通过对比研究红树林源有机碳贡献和红树孢粉组合特征,揭示百年来钦州湾红树林兴衰和群落演替规律;进而重塑其红树林演变历史:兴盛期(1864-1918年)、衰退期(1918-1968年)和低谷期(1968-2007年),这与土地替代、遥感分析和现场勘测数据较为吻合。结合气候变化和人类活动资料,发现钦州湾红树林的近期衰退主要源于人类活动的影响,尤其是虾塘围垦;而与气候变化关系不大。     

有效群体大小对蛤仔F1生长和存活影响

对不同有效群体大小(Ne=2、4、8、16、32、200)的蛤仔F1代生长和存活性状进行了比较。结果表明:浮游期,各试验组幼虫壳长均未表现出显著性差异(P0.05),实验组Ne=200的存活率低于其他各实验组,并随着日龄的增长,差异越来越显著;稚贝期,各实验组的壳长和存活率的变化规律和浮游期基本一致。对壳长变异情况分析表明,浮游期,随着群体有效含量的增大,子代开始出现小型个体和大型个体,壳长分布变异逐渐明显;稚贝期,各试验组组内壳长变异进一步加剧,除Ne=2试验组稚贝壳长介于400μm和600μm之间外,其他各试验组均出现明显的小型和大型个体,表现为有效群体越大,组内稚贝壳长变异越为明显。     

Distribution of <Emphasis Type="Italic">Nemopilema nomurai</Emphasis> in the southwestern Sea of Japan related to meandering of the Tsushima Warm Current

We investigated the horizontal distribution of Nemopilema nomurai medusae using a midwater trawl in the southwestern Sea of Japan from September to October of each year from 2006 to 2012. Numerous medusae of this species found in 2006, 2007, and 2009 were mainly distributed far (>40 km) from the mainland of Japan in the western part of the survey area, but were distributed in the stations closest (<25 km) to the mainland in the eastern part, particularly in 2006 and 2009. These distribution patterns were associated with the path of the second branch of the Tsushima Warm Current (TWC) that flows offshore to the west of Oki Islands and usually approaches the mainland of Japan to the east of Oki Islands. Differences in jellyfish distribution across the survey periods were related to the distribution of the second branch being associated with types, position and intensity of eddies in the eastern part of the survey area. Hence, the formations of eddies and consequent variation in the path of the TWC would be responsible for transporting medusae from offshore to near the mainland to the east of Oki Islands. Individuals with large bells accumulated in the northwestern part of the survey area, where a cyclonic eddy was present downstream of the third branch of the TWC. This variation in bell size distribution may be ascribed to differences in the physical and/or biological factors among the three branches of the TWC.     

斑马鱼GSTM单核苷酸多态性与低温耐受性的相关分析

为分析谷胱甘肽硫-转移酶M基因(glutathione S-transferases M,GSTM)与鱼类低温耐受性的相关性,本实验运用PCR-SSCP技术研究了130尾斑马鱼(Danio rerio)GSTM基因5?UTR、3?UTR和第一内含子序列的单核苷酸多态性(Single nucleotide polymorphisms,SNPs),同时分析了筛选到的基因型与其低温耐受性状的关联性。结果显示,在其5UTR区域检测到AB、BC、AC 3种基因型个体,共A、B、C 3个等位基因,其观测杂合度和期望杂合度分别是1.000和0.570,多态信息含量为0.472,所检测群体在该座位偏离了Hardy-Weinberg平衡;第1内含子中检测到DD、DE和EE 3种基因型个体,共D、E两个等位基因,其观测杂合度和期望杂合度分别为0.408和0.477,多态信息含量为0.362,群体在该座位符合Hardy-Weinberg平衡。3'UTR区域中没有发现多态性。上述2个SNP座位与斑马鱼低温耐受性状的关联分析结果表明,5'UTR区3种基因型与低温耐受性状均没有显著相关性(χ2=4.029,P0.05)。而第1内含子3种基因型与低温耐受性状显著相关(χ2=8.498,P0.05):DD基因型在耐低温群体中占优势(50.00%),并表现为对受低温胁迫斑马鱼的保护性因素(OR=0.520,95%CI=0.255–1.061),而DE基因型在不耐低温群体中占优势(51.31%),表现为低温胁迫下斑马鱼的危险因素(OR=3.012,95%CI=1.413–6.419)。研究结果为GSTM基因SNPs位点与斑马鱼低温耐受性能关联分析提供了依据,也将为海水经济鱼类抗寒标记筛选育种提供参考。     

西太平洋夏季三类声速环境下的会聚区特性比较

利用Argo剖面数据和水声学数值模型,分析了西太平洋夏季在热带海区(I型)、亚热带南部海区(II型)和亚热带北部海区(III型)三类典型声速环境下的会聚区特性。声场计算结果表明,声速环境的区域性差异及声源深度的变化对会聚区声场特性有明显影响。当声源深度为20m时,热带海区会聚区距离较远,第一会聚区约为65km,超出亚热带海区约5km;当声源深度为200m时,亚热带北部海区会聚区距离较远,第一会聚区约为60km,亚热带南部海区、热带海区依次递减约5km。I型和III型剖面在特定的声源深度条件下出现波导型声场,当声源位于表层时热带海区产生表面波导,当声源位于次表层时亚热带北部海区产生次表层波导,对于1kHz的声波,波导深度范围内的传播损失比波导深度以外高出10~20dB。     

Impacts of the two types of El Niño on Pacific tropical cyclone activity

It is well known that Tropical cyclone(TC) activities over the Pacific are affected by El Nino events. In most studies El Nino phenomena have been separated into east Pacific warming(EPW) and central Pacific warming(CPW) based on the location of maximum SST anomaly. Since these two kinds of El Nino have different impacts on Pacific tropical cyclone activities, this study investigates different features of TC activities and the genesis potential index(GPI) during EPW years and CPW years. Four contrib- uting factors, i.e., the low-level absolute vorticity, the relative humidity, the potential intensity and the vertical wind shear, are exam- ined to determine which factors are most important in causing the anomalous TC activities. Our results show that during EPW years in July–August(JA0), TC activities are more frequent with stronger intensity over the Western North Pacific(WNP) and Eastern North Pacific(ENP). The maximum anomaly center of TC activities then drifts eastward significantly in September–October(SO0). However, centers of anomalous TC activity barely change from JA0 to SO0 during CPW years. In January–February–March(JFM1) of the decaying years of warming events, TC frequency and intensity both have positive anomaly over the South Pacific. The anoma- lies in EPW years have larger amplitude and wider spatial distribution than those in CPW years. These anomalous activities of TC are associated with GPI anomaly and the key factors affecting GPI anomaly for each ocean basin are quite different.     

邹城市双村岩溶水系统水化学演化分析

以山东省邹城市双村岩溶水系统为研究对象,利用多年水质监测资料对主要离子含量的变化特征及分布规律进行研究比对,分析地下水开采及生活污染对地下水水化学环境的影响,有助于认识在人类生产活动影响下的水化学场时空演化,为地下水合理开发、水源保护提供参考依据。     

中国钼金属矿床特征及资源潜力分析

钼是重要的战略性矿产资源。我国的钼矿床类型多样,主要分为内生和外生等5种类型,其中斑岩型矿床是最重要的矿床类型。钼矿床分布具有区域分带的特点,这种特点与其成矿动力学背景密切相关。在今后钼矿床的勘查找矿工作中,把加强已有矿山的深部和外围找矿与开展非传统地区的勘查找矿相结合,重视内生矿床尤其是斑岩型矿床的成矿潜力,以实现钼矿床的找矿新突破。