2018/2019年冬季浙江罕见持续阴雨天气的环流异常与海温强迫

利用NCEP/NCAR全球再分析资料、地面观测资料和自动站降水资料,分析了2018/2019年冬季浙江罕见连续阴雨寡照天气过程中冬季风环流和南支槽等环流异常,并从西风带波动、海温强迫等方面研究了局地环流异常的成因。结果表明:2018/2019年冬季连阴雨事件中雨日、日照破历史记录,雨量较常年同期明显偏多。主要的环流异常为西北太平洋异常反气旋（WNPAC）明显偏北,同时阿留申低压和西伯利亚高压亦偏北,东亚地区40°N以南有强的偏南风异常,冬季风偏弱;南支槽较常年偏强,保证了浙江上空有持续的水汽和扰动输送。对流层中层存在沿欧洲向东亚—西太平洋传播的波动能量,波能在东亚地区一直向南传播至20°N以南,可能导致WNPAC明显北抬和南支槽加强。ENSO是WNPAC的重要强迫源,ENSO暖位相使得海洋性大陆出现异常对流冷却,而浙江上空对流加强,ENSO对南支槽活动强度亦有明显的制约作用。中国近海海温偏高是WNPAC和阿留申低压明显偏北的重要影响因素。2018/2019年冬季局地环流异常可能由ENSO和中国近海海温协同强迫所致。     

The Time-Frequency Energy Attenuation Factor and Its Application on the Basis of Gauss Linear Frequency-Modulated Continuous Wavelet Transform

Based on the Gauss linear frequency-modulated wavelet transform, a new characteristic index is presented, namely time-frequency energy attenuation factor which can reflect the difference features of waveform in earthquake focus mechanism, wave traveling path and its attenuation characteristics in focal area or near field. In order to test its validity, we select the natural earthquakes and explosion or collapse events whose focus mechanisms vary obviously, and some natural earthquakes located at the same site or in a very small area. The study indicates that the time-frequency energy attenuation factors of the natural earthquakes are obviously different with that of explosion or collapse events, and the change of the time-frequency energy attenuation factors is relatively stable for the earthquakes under the normal seismicity background. Using the above-mentioned method, it is expected to offer a useful criterion for strong earthquake prediction by continuous earthquake observation.     

中国大陆动力学研究进展——纪念中国地球物理学会成立60周年

本文简要地回顾了中国大陆动力学研究发展的历史、特点和主要成果,存在的主要问题,提出相应的改进建议.(1)我国大陆动力学研究是从1926年李四光发表《地球表面形象变化之主因》一文开始的,他肯定大陆漂移说的革命意义和不足之处,提倡和坚持了用力学原理研究地壳运动和变形,主张用多学科方法,构造体系的观点对构造运动和变形进行概括,强调要从原理上探究地质作用的发生是否可行等等,这是中国的光荣传统之一.(2)当代大陆动力学的研究是以深部调查为基础,以岩石圈为研究对象,进行三维演化的探讨.提出它是以地质学、地球物理学,地球化学,大地测量学,地质力学和高温高压实验地质学理论知识为基础的综合性学科.是研究地球成矿作用、地震火山地质灾害发生机制的基础.这是当代地球科学发展的主要趋向,且日趋深入和扩大.(3)我国深部调查工作是1958~1962曾融生在柴达木盆地所作地震测深试验开始的.从上世纪80年代扩大了工作规模,并随着国际地学的发展而不断深入和扩大,先后工作在青藏高原,大别山变质岩带,秦岭造山,华南花岗岩区,以及南海新生边缘海盆等地区,现在又转向天山造山带和华北大陆地区（研究大陆减薄与裂解问题.此外,还结合全国地震带,成矿带进行工作.已获得了丰富的科学成果,引起国际地学界的重视.(4)工作的主要体会是：如,深部研究要以地壳上地幔为对象,并力求结合实际资源、环境科学问题的探讨,以利于深化认识;要坚持多学科综合应用,特别是加强构造动力学的分析,提高深部探测技术,处理方法和软件水平,重视深源包体采集和研究;大陆深钻应与综合调查紧密结合;要以我为主积极与外国合作,与国际接轨,不能盲目跟“风”.(5)提出我国大陆动力学研究存在“一少”、“二乱”、“三假”、“四霸”的现象,及其产生的根源作了分析,并提出改进的对策建议.当前更需要我们有 “志气”走出一条自己的路,创造一个好的学术“环境”.     

Modeling of Wave Dispersion Using Continuous Wavelet Transforms

In the estimate of dispersion with the help of wavelet analysis considerable emphasis has been put on the extraction of the group velocity using the modulus of the wavelet transform. In this paper we give an asymptotic expression of the full propagator in wavelet space that comprises the phase velocity as well. This operator establishes a relationship between the observed signals at two different stations during wave propagation in a dispersive and attenuating medium. Numerical and experimental examples are presented to show that the method accurately models seismic wave dispersion and attenuation.     

Frictional effects on trapped shelf waves

This paper revisits models of coastal trapped waves and examines them with the inclusion of friction. In addition we use a numerical method which at least theoretically will have enhanced accuracy. The model has continuous stratification and variable depth. It is linear, quasigeostrophic and hydrostatic, and utilizes perturbation from this fundamental state. The model is applied with both idealized and realistic topography and stratification.Responsible Editior: Phil Dyke     

海水中叶绿素α含量的连续走航测定

介绍一种适用于各种船只有海水叶绿素含量连续走航自动测定系统，它包括海水取样，荧光测量，数据采集和数据处理单元，这一系统已用于１９９４年在东海的两个航次的考察。数据采取的间隔可根据研究项目的需要确定，在东海的考察中，确定的间隔为ｌｓ，实际是每０．１ｓ取一个数据，记录每秒间隔内的平均值，共获得６０万个观测值，得出的平面分布与传统的站位上采水样观测结果的总趋势一致，但走航观测的结果更详细，包括从几十米至     

石煤中钒元素在燃烧前后赋存状态变化的研究

石煤是一种可综合利用的矿产资源,提取石煤中钒、钼、镍等金属是其综合利用之一.石煤在发电燃烧过程中钒的物相发生显著变化,而钒物相的变化对钒的可浸出性产生较大的影响.笔者采用选择性连续提取方法对四川某地石煤原矿和石煤飞灰进行分析研究,发现石煤原矿中钒主要存在于硅铝酸盐相和有机质相中,部分存在于铁锰氧化物相及吸附态中,极少部分存在于碳酸盐相中.而石煤发电飞灰中钒主要存在于有机质相、硅铝酸盐相和铁锰氧化物相中,少量的钒以吸附态形式赋存.燃烧过程中石煤的各种含钒矿物发生离解,其中的钒得到释放并被氧化成高价态.高价钒一部分与Na、Cl等结合生成可溶性化合物,形成吸附态的钒;另一部分与Fe、Na、Ca等发生反应生成难溶性化合物,并以一定形式富集在飞灰的有机质相、硅铝酸盐相和铁锰氧化物相中.     

华北地区持续性极端暴雨过程的分类特征

利用1960—2015年日降水资料,筛选出华北地区56次持续性极端暴雨过程。基于距平相关系数的客观聚类分析方法和天气学检验,将它们进行分类,并使用NCEP（2.5°×2.5°）再分析资料进行分类合成,对比分析不同环流背景下华北地区持续性极端暴雨过程的基本特征。结果表明,这些持续性极端暴雨事件按照环流背景可分为经向型、纬向型、减弱的登陆热带气旋型和初夏型4类。它们一般都与不同天气系统配置结构下的锋面动力学过程有关,由于锋面结构特征、环境大气层结状态以及与低空急流有关的暖湿气流输送通道和强度不同,造成不同环流形势背景下,暴雨日的高频站点与过程平均累计降水量在空间分布上存在差异。（1）纬向型对应的锋区强度明显强于经向型,但是其对应的层结稳定度与整个夏季状态相当,而经向型存在弱的层结不稳定异常,这表明,纬向型的对流活动一般不如经向型强,持续性锋面降水特征更清晰,造成站点上日降水量超过50 mm的最大频率明显低于经向型,但是过程累计平均最大降雨量却比经向型大。（2）从水汽输送通道来看,源于西太平洋副热带高压南侧的水汽通道只在纬向型环流主导下的华北区域持续性极端暴雨过程中起主导作用。初夏型以及减弱的登陆热带气旋与西风带系统相互作用造成的极端暴雨过程中,活跃的印度季风造成25°N以南异常强盛的纬向低空西南气流携带充沛的水汽,穿过中南半岛后以西南低空急流或者通过减弱的登陆热带气旋“中转”,是这两类暴雨区的主要水汽供应方式;经向型环流背景下的水汽输送也与这支源于青藏高原南侧的西风气流异常有关。这可能是华北地区夏季降水与印度季风降水的相关显著强于中国东部其他地区的主要原因。（3）减弱的登陆热带气旋与西风带系统相互作用造成的极端暴雨事件同样由经向型环流主导,但是,更充沛的水汽输送、更强的上升运动和更深厚的大气不稳定层结状态是它比一般的经向型强度更大的直接原因;此外,中高纬度弱冷空气侵入对减弱的登陆热带气旋顶部形成持续性极端暴雨过程非常重要。      

Fractionation and concentration of suspended particulate matter in natural waters

A scheme for the fractionation and concentration of suspended particulate matter (SPM) from natural waters has been tested. This scheme involves the sequential use of three fractionation techniques—sieving, continuous flow centrifugation and tangential flow filtration to collect gram amounts of SPM over the entire particulate and colloidal size range. The separation scheme is able to process large samples (ca. 1001), within reasonable times (ca. 1 day) and the apparatus is portable. Reproducibility and potential artifacts introducing during the fractionation and concentration of SPM, particularly when tangential flow filtration is used, are discussed. It has been shown that there is a systematic increase in the content of organic carbon, Mg, Ca, Na, K, Cu and Zn with decreasing particle size, highlighting the importance of the colloidal ( < 1 μm) fraction.     

Automated facies identification by Direct Push-based sensing methods (CPT,HPT) and multivariate linear discriminant analysis to decipher geomorphological changes and storm surge impact on a medieval coastal landscape

In ad 1362, a major storm surge drowned wide areas of cultivated medieval marshland along the north-western coast of Germany and turned them into tidal flats. This study presents a new methodological approach for the reconstruction of changing coastal landscapes developed from a study site in the Wadden Sea of North Frisia. Initially, we deciphered long-term as well as event-related short-term geomorphological changes, using a geoscientific standard approach of vibracoring, analyses of sedimentary, geochemical and microfaunal palaeoenvironmental parameters and radiocarbon dating. In a next step, Direct Push (DP)-based Cone Penetration Testing (CPT) and the Hydraulic Profiling Tool (HPT) were applied at vibracore locations to obtain in situ high-resolution stratigraphic data. In a last step, multivariate linear discriminant analysis (LDA) was successfully applied to efficiently identify different sedimentary facies (e.g., fossil marsh or tidal flat deposits) from the CPT and HPT test dataset, to map the facies' lateral distribution, also in comparison to reflection seismic measurements and test their potential to interpolate the borehole and CPT/HPT data. The training dataset acquired for the key site from coring and DP sensing finally allows an automated facies classification of CPT/HPT data obtained elsewhere within the study area. The new methodological approach allowed a detailed reconstruction of the local coastal landscape development in the interplay of natural marsh formation, medieval land reclamation and storm surge-related land losses.