Application of the New Wavelet-Decomposition Method for the Analysis of Geomagnetic Data and Cosmic Ray Variations

Geomagnetism and Aeronomy - The potential use of the wavelet-decomposition method developed by the authors for the analysis of geomagnetic data and cosmic ray variations is studied. With the use of...     

Solar Activity,Galactic Cosmic Ray Variations,and the Global Seismicity of the Earth

Geomagnetism and Aeronomy - A comparative analysis of the correlation between the number of strong (magnitude M ≥ 5.0), crustal (hypocenter depth 0 ≤ h ≤ 60 km) earthquakes per...     

Possible Contribution of Variations in the Galactic Cosmic Ray Flux to the Global Temperature Rise in Recent Decades

The field area of the Earth’s lower (<3.2 km) clouds is shown to correlate significantly with the intensity of galactic cosmic rays in 1983–2010, with the sign of correlation reversing in 2003. The same effect is discovered in the correlation between air temperatures in various regions of the Earth and the relativistic electron fluxes with energies of 30–300 KeV that precipitate in winter (December–February). An energy-balance climate model is used to estimate the possible contribution of lower clouds to the globally averaged temperature in the indicated period. It is shown that the consideration of lower clouds as a radiative forcing allows one to explain the global warming of the last 30 years without employing the hypothesis of anthropogenic greenhouse heating.

     

Variations of Geomagnetic Cosmic Ray Thresholds and Their Latitudinal Behavior in the Period of Solar Disturbance in September 2005

The period of interplanetary, geomagnetic and solar disturbances of September 7–15, 2005, is characterized by two sharp increases of solar wind velocity to 1000 km/s and great Dst variation of the geomagnetic field (~140 nT). The time variations of theoretical and experimental geomagnetic thresholds observed during this strong geomagnetic storm, their connection with solar wind parameters and the Dst index, and the features of latitudinal behavior of geomagnetic thresholds at particular times of the storm were studied. The theoretical geomagnetic thresholds were calculated with cosmic ray particle tracing in the magnetic field of the disturbed magnetosphere described by Ts01 model. The experimental geomagnetic thresholds were specified by spectrographic global survey according to the data of cosmic ray registration by the global station network.     

Influence of the Solar Wind and Geomagnetic Activity Parameters on Variations in the Cosmic Ray Cutoff Rigidity during Strong Magnetic Storms

Geomagnetism and Aeronomy - The correlation between the variations of geomagnetic cutoff rigidity ΔR and interplanetary parameters and the Dst index of geomagnetic activity during one moderate...     

Ground-based Instrument for the Study of Cosmic Ray Variation in Nur-Sultan

Geomagnetism and Aeronomy - Cosmic rays are the main factor in atmospheric ionization; they affect the formation of clouds and determine the properties of the global electrical circuit. The...     

Galactic Cosmic Ray Intensity in the Upcoming Minimum of the Solar Activity Cycle

During the prolonged and deep minimum of solar activity between cycles 23 and 24, an unusual behavior of the heliospheric characteristics and increased intensity of galactic cosmic rays (GCRs) near the Earth’s orbit were observed. The maximum of the current solar cycle 24 is lower than the previous one, and the decline in solar and, therefore, heliospheric activity is expected to continue in the next cycle. In these conditions, it is important for an understanding of the process of GCR modulation in the heliosphere, as well as for applied purposes (evaluation of the radiation safety of planned space flights, etc.), to estimate quantitatively the possible GCR characteristics near the Earth in the upcoming solar minimum (~2019–2020). Our estimation is based on the prediction of the heliospheric characteristics that are important for cosmic ray modulation, as well as on numeric calculations of GCR intensity. Additionally, we consider the distribution of the intensity and other GCR characteristics in the heliosphere and discuss the intercycle variations in the GCR characteristics that are integral for the whole heliosphere (total energy, mean energy, and charge).     

2013 年芦山MS7.0 地震前甘孜台地电阻率变化分析

A trend increase in apparent resistivity has been observed in the N30°E monitoring direction at Garze Seismic Station since July 2011. This increase trend in geo-electric resistivity has been observed in the N60°W direction since 2012. During the period of the increase, the national highway No.317 was expanded in the monitoring area, so the potential electrodes in the N30°E direction had to be moved 10m towards the current electrodes. We interpreted the electric sounding data of Garz6 Seismic Station with a horizontally layered model. Analysis based on this model showed that the shift of potential electrodes can cause a 4 l-l.m rise to the measurements in the N30°E direction. Therefore, apparent resistivity of the two directions increased in the same time in 2012 after offsetting the effects from electrodes shift. Sensitivity coefficients of the two observation directions were also obtained using the model. Sensitivity coefficients of both directions were negative for the shallow layers, which can well explain the unexpected annual variations of Garze Seismic Station. In order to quantitatively analyze the effects from the expansion of the national highway on the observation, we constructed a finite element model based on the electrical structure. Analysis results also suggested that the expansion of the national highway could only cause a 0. 15 Ω·m decrease in the N60°W monitoring direction and 0. 1 Ω· m increase in the N30°E direction. Additionally, the valley values of annual variation of 2013 were distinctively higher than that of other years since 2008, meaning that there was an abnormal rise in apparent resistivity in the two observation directions at Garz~ Seismic Station before the Lushan earthquake. However, the rise was contrary to the decline variation before the Wenchuan earthquake. Therefore, it is still unsure whether or not the rise variation is related to the Lushan earthquake.     

Station-Ring Method in the Study of Cosmic-Ray Variations: 2. Examples of Its Use

Geomagnetism and Aeronomy - The station-ring method makes it possible to isolate and study the specific angular distributions of cosmic-ray variations that are poorly described by the sum of the...     

Earthquake Research in China General Contents,Vol.1 6(2002)

Ｎｏ .1ＰｒｏｇｒｅｓｓｉｎＥａｒｔｈｑｕａｋｅＳｃｉｅｎｃｅａｎｄＴｅｃｈｎｏｌｏｇｙｉｎＣｈｉｎａ :ＲｅｖｉｅｗａｎｄＰｒｏｓｐｅｃｔ (ＩＩ)ＣｈｅｎＺｈａｎｇｌｉ ( 1 )……………………………………………………………………………ＳｃａｌｉｎｇｏｆＲｅｄｕｃｅｄＥｎｅｒｇｙｏｒＡｐｐａｒｅｎｔＳｔｒｅｓｓａｎｄＩｔｓＳｅｉｓｍｏｌｏｇｉｃａｌＳｉｇｎｉｆｉｃａｎｃｅＷｕＺｈｏｎｇｌｉａｎｇ ( 2 0 )…………………………………………………………………………Ｒｅｓｅａｒｃｈｏｎｔｈｅ 3 ＤＳｅｉｓｍｉ…     

Cosmic Rays during Forbush Effects in March 1989 and March 1991: Spectra of Variation,Anisotropy, and Variations of Geomagnetic Cutoff Rigidity

Geomagnetism and Aeronomy - Two Forbush effects that occurred during geomagnetic storms in March 1989 and March 1991 are analyzed based on ground-based measurements of cosmic rays at a global...     

基于Pushover分析方法的多层地铁车站地震反应研究

为系统研究多层地铁车站结构地震反应,本文采用地下结构Pushover分析方法对Ⅱ、Ⅲ类场地9座不同结构形式的地铁车站结构进行系列拟静力推覆分析。研究结果表明：中柱是多层地铁车站结构关键抗震构件,地震作用下易先于其他构件产生损伤甚至破坏,车站结构出现整体性塌毁主要是由于中柱首先产生剪切破坏而丧失竖向承载力导致的。中柱是地铁车站结构重要的竖向承力构件,侧墙是地铁车站结构主要水平承力构件。损伤演变速度及损伤累计程度排序为中柱>侧墙>板。对于多层地铁车站结构而言,结构底层中柱和侧墙通常承受更高的轴压作用,使其损伤和破坏先于上层构件。中柱顶、底端和墙、板交界位置在地震作用下极易产生损伤破坏,建议在抗震设计中对这些位置适当地进行加强处理。     

小波分析法在海拉尔地震台前兆数据处理中的应用研究

应用小波变换法可对不同频率成分进行分解的特性,选取d b4小波基函数,尺度为1～8阶,对海拉尔地震台前兆资料进行分析研究.结果表明,应用小波变换方法可较容易地识别和剔除气压、场地环境干扰等影响海拉尔地震台伸缩仪观测资料精度的诸多因素,气压和场地环境干扰在小波细节分解d3～d6部分异常显著;小波变换法对同震效应的识别、提...     

兰州和海拉尔核查地震台阵慢度和方位角校正方法研究

介绍了一种地震台阵慢度和方位角格点校正方法,在预定义的格点空间调整校正慢度和方位角,从而消除系统偏差,提高地震台站慢度与方位角估计的精度。利用该方法对我国核查地震台阵海拉尔和兰州方位角和慢度进行了校正,离线和在线的测试显示了台站慢度和方位角估计性能的提高。     

广州地铁西村站近接桩基沉降现场监测方法及其应用

以广州地铁西村站近接9组桩基施工为例,运用三维数值模拟技术,研究了近接桩基沉降现场监测方法,建立了西村站近接桩基沉降控制标准、监控量测管理等级和监控量测频率。对西村站9组近接桩基沉降现场监测值及计算值分析的结果表明：9组近接分区桩基沉降现场实测值与采取加固措施后的近接分区桩基沉降计算值基本一致,仅桩基X J27和X J31略有不同,现场实测值略大一些,桩基X J27由C区变为B区,桩基X J31由D区变为C区;桩基X J34沉降过大的原因主要是,加固措施的施工质量未达标以及开挖到桩基X J34相应位置时对围岩扰动过大;提出的广州地铁西村站近接桩基沉降现场监测方法是正确的。     

Earthquake Research in China General Contents, Vol. 19 （2005）

No.1Characteristics of Energy Accumulation and Release of Seismogenic Tectonics and Seismic RiskAnalysis in Some Areas inthe Tianshan Mountains,Xinjiang Shen Jun,Li Yingzhen and Wang Yipeng…………………………………………(1)Regional Tectonic Deformation B