黄石台ORBES-81型伸缩仪观测结果的调和分析及海潮改正

本文对黄石台ORBES-81型石英伸缩仪的应变固体潮观测资料作了分析计算,其调和分析结果为:对O₁波,振幅因子0.4219,相位滞后6°36＇;对M₂波,振幅因子0.4256,相位滞后-4°42＇.同时,讨论了海潮引起的负荷潮汐应变的改正问题.模拟计算发现负荷潮汐应变与体潮应变大致为同一量级,文中列出了海潮改正后的结果,并作了讨论.最后,对黄石台伸缩仪的架设方位作了评价.     

武汉国际重力潮汐基准研究

通过综合分析8台重力仪潮汐观测结果,精密确定了武汉国际重力潮汐基准值.与Dehant重力潮汐模型同时考虑(1)全球卫星测高海潮资料和(2)Schwiderski海潮加中国近海海潮资料的结果相比,振幅因子差和相位滞后差分别为5.2‰,3.6‰和0,16°,0,08°.该结果明显优于早期确定的基准值,说明利用长系列超导重力仪观测同时考虑精密海洋负荷和地核近周日摆动效应是提高国际重力潮汐基准的重要途径.     

南极中山和长城站重力潮汐观测研究

利用3台LaCoste-Romberg型弹簧重力仪（G-589、ET-20和ET-21）在南极中山站和长城站的长期重力潮汐观测资料，在武汉国际重力潮汐基准上精密测定了中山站和长城站的重力潮汐参数，其中主波振幅因子的标准偏差优于0.5％．各潮波的观测振幅在中山站比在长城站的小得多，两站周日潮（O1）的观测振幅因子相差约7％，而半日潮（M2）的观测振幅因子相差超过40％，气压和温度等气象因素的变化对观测结果的影响很明显．海潮负荷对两台站潮汐观测的影响非常显著，采用Schwiderski全球海潮模型对观测结果作海潮负荷重力改正．结果表明，经海潮改正后，各潮波的观测残差有较大幅度的减小，但是，由于采用的海潮模型没有顾及台站近区的海潮负荷效应，所以，O1 波的振幅因子对相应理论潮汐模型值之间存在大约4％（中山站）和9％（长城站）的偏差．      

基于全球超导重力仪观测研究海潮和固体潮模型的适定性

利用国际地球动力学合作观测网络中20个台站22个高精度重力潮汐观测系列综合研究了目前使用的海潮和固体潮模型的适定性. 对原始观测数据实施仔细的预处理, 利用国际标准算法计算了潮汐重力参数. 基于负荷理论和不同全球海潮模型获得了8个主波的重力负荷矢量, 用二维平面插值技术获得了14个小波的负荷改正值. 顾及不同潮波振幅特征, 提出了计算台站平均观测残差和剩余残差矢量的“非等权均值法”, 分析了海潮负荷改正的有效性和振幅因子与理论模型间的差异, 同时还讨论了仪器标定问题. 获得了经海潮负荷改正后全球各台站平均潮汐重力参数, 结果说明观测与理论模型间的差异小于0.3%, 最大仪器标定误差不超过0.5%. 另外文章还用地表重力实测数据证实了Mathews理论中相对于周日O₁波而言, K₁波相位滞后略呈正值的结论.     

大连台重力固体潮受海潮负荷影响特征研究

大连台重力固体潮汐观测受海潮负荷影响较大,选取2015年1月1日～2019年8月14日的重力数据进行预处理,获得重力潮汐参数,基于选取的8个海潮模型对O₁、K₁和M₂波进行海潮负荷改正及评价分析。数值分析结果表明,O₁、K₁和M₂波的重力海潮负荷振幅分布频段在2.4～2.8μGal之间,3个主潮波的残差负荷改正有效性为43％～53％,8个海潮模型对大连台主潮波的海潮负荷改正差别较小。     

中国大陆M2波理论应变潮汐模型

本文主要研究和讨论了我国大陆固体潮和海潮负荷效应的M₂波理论应变潮汐模型。推导了球扇波应变张量大地系数和计算公式,着重研究和计算了M₂波海潮应变负荷效应,讨论了计算方法,计算中采用了到目前为止最新的Schwiderski（M₂）全球海潮图和沈育疆近中国海潮汐图;给出了40个点的负荷效应结果,并绘制了中国大陆固体应变潮、海潮应变负荷效应同相位,相差π/2相位以及总效应的应变花。为理论研究,观测资料的分析和改正提供了理论参考模型。     

泰安台YRY-2钻孔应变仪线差应变潮汐参数及其稳定性研究

介绍了泰安地震台YRY-2钻孔应变仪1991～1996年观测数据的调和分析结果．分析了潮汐参数的动态特征及其稳定性，并将有关结果与洞体水平线应变仪的（伸缩仪）观测结果进行了对比分析．泰安地震台YRY-2钻孔应变仪NS分量M2波月潮汐因子的离散中误差为3.3％，NE分量为3.6％，相位滞后的月离散误差小于2°．该指标与最好的洞室仪器SSY-Ⅱ的结果相当．     

攀枝花地震台应变固体潮调和分析

本文采用Venedikov调和分析方法,对攀枝花地震台1989年至1990年两年的石英伸缩仪应变固体潮观测资料进行了调和分析,并根据Venediov调和分析结果,分析研究了M_2波的潮汐因子和相位滞后因子的动态变化,从中获得了与地震有关的信息,这对今后的地震分析预报具有一定前参考价值。     

庐江台自流井流量固体潮观测资料调和分析的初步结果

用LW—150型涡轮流量变送器、CZ—1002型数字记录仪组成的观测系统,在庐江台自流井进行了流量固体潮观测。将固体潮体应变的理论值作为流量潮的理论值,用维涅第柯夫方法对7个月的流量观测数据(各整点7分28秒内累计脉冲数)进行了调和分析,主要潮波的结果为: 振幅因子相位滞后 O_1波 6.17±0.08 -3.7°±0.7° M_2波 6.32±0.03 8.7°±0.3°这显示了较好的潮汐观测质量。同时,观测结果还反映了该观测系统具有良好的长期稳定性。     

承压井水位固体潮M_2波海潮负荷改正

应用Schwiderski全球海潮模型,采用积分格林函数方法计算了海潮M2波的应变负荷潮。通过调和分析和残差计算,对京、津、唐地区的7个承压水位观测井的水位固体潮M2波进行了海潮负荷改正。计算结果显示,观测井水位M2波潮汐因子和相位漂移的标准偏差分别由改正前的2.263和24.57°降低到0.898和3.58°。     

A Monte Carlo study of rainfall forecasting with a stochastic model

A procedure for short-term rainfall forecasting in real-time is developed and a study of the role of sampling on forecast ability is conducted. Ground level rainfall fields are forecasted using a stochastic space-time rainfall model in state-space form. Updating of the rainfall field in real-time is accomplished using a distributed parameter Kalman filter to optimally combine measurement information and forecast model estimates. The influence of sampling density on forecast accuracy is evaluated using a series of a simulated rainfall events generated with the same stochastic rainfall model. Sampling was conducted at five different network spatial densities. The results quantify the influence of sampling network density on real-time rainfall field forecasting. Statistical analyses of the rainfall field residuals illustrate improvement in one hour lead time forecasts at higher measurement densities.     

Earthquake Engineering and Engineering Vibration Aims And Scope

正This journal is established by the Institute of Engineering Mechanics(IEM),China Earthquake Administration,to promote scientific exchange between Chinese and foreign scientists and engineers so as to improve the theory and practice of earthquake hazards mitigation,preparedness,and recovery.To accomplish this purpose,the journal aims to attract a balanced number of papers between Chinese and     

Foreword

Destructive earthquakes have caused great damage in China and the United States and collapsing buildings havecaused many deaths and injuries. The field of earthquake engineering studies earthquake hazards, the occurrence ofearthquakes of various magnitudes, the nature of the ground shaking during an earthquake, the vibration of structuresduring earthquakes, the strengthening of existing structures and the design of new structures to be earthquake resistant,and finally, how to cope with earthquake damage and restore a city to normal functioning. Such efforts are in progressin both countries, but unfortunately, the language barrier interferes with the free flow of information between China andthe Untied States. It would be mutually beneficial if some means could be developed to promote the exchangeof information across the Pacific Ocean. This new journal has been established for this purpose and its success willbe an important step in promoting earthquake engineering in China and the United States.     

WORLD ASSOCIATION FOR SEDIMENTATION AND EROSION RESEARCH(WASER)

正President:Giampaolo Di Silvio,Italy Vice Presidents:Ulrich C.E.Zanke,Germany Zhao-yin Wang,China The World Association for Sedimentation and Erosion Research(WASER),inaugurated on Oct.19,2004,is an independent non-governmental,non-profit organization.The mission of WASER is to promote international co-operation on the study     

Enhancing remote sensing research on global change to improve our understanding on Earth system processes

正Global Change includes climate change and other environmental changes caused by the joint interaction among various layers of Earth. From the positive side, global change provides new opportunities to human and other living forms on Earth. In the meantime, it creates tremendous challenges and negative impact. At present, the negative impacts have reached all primary processes of the global ecosystem and every aspect of human society, especially causing degradation of the ecosystem. For instance, intensive deforestation causes decline of biodiversity; global warming causes sea level rise and increases     

Solute concentrations in the lower niger river and the source rock contribution

Water quality analyses for the Niger River for the 1980/81 hydrological year are presented. The samples were collected from the main river at Lokoja, and from two main tributaries, the Kaduna and the Benue Rivers. Different water types were distinguished by the concentrations of major ions. The type Ca > Na > Mg > K - HCO₃ > SO₄ > Cl was represented at all stations during at least part of the year. Chloride was found to dominate the sulphate ion in the Kaduna and Niger, while the Benue maintained a higher concentration of sulphate relative to chloride all year round. Distinct patterns of seasonal variation in the ion concentrations were observed, particularly for the samples collected at Lokoja. Low ion concentrations were prominent during periods of high discharge, while low flow periods coincided with high dissolved ion concentrations. The contribution of rainwater to the total dissolved solids in the river waters was assessed indirectly using rainwater chemistry data from the Gulf of Guinea. The estimated rainwater contribution to the Lower Niger amounts to 5.15 mg 1^?1. Geochemical weathering calculations involving reactions of the four major minerals of granitic rocks - anorthite, biotite, albite, and K-feldspar - with carbon dioxide and water, can account for the average water composition of the Lower Niger. The proportion of the ionic components was also related to the occurrence of the respective element in the minerals.