共查询到20条相似文献，搜索用时 140 毫秒
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因太阳活动而引起的地磁扰动,会在地球表面感生出地电场,从而在地表附近的导体系统中产生地磁感应电流(GICs).太阳表面的异常活动而引起的磁暴会导致强烈的GICs,严重威胁电信设备、电网、油气管道和铁路运输网络等基础设施系统的安全运行,已经成为最严重的空间天气灾害之一.因此,对GICs进行深入研究以建立对其做出迅速预测的能力,在科学和应用方面都有重要意义.本文综述了GICs的研究进展,从引入空间天气的概念开始,将GICs作为从太阳活动到太阳风再到地球扰动的空间天气链的最终环节;重点阐述了GICs的计算中所涉及的三个步骤:地球表面地磁场重建、感应地电场的计算,以及地面导体系统中GICs计算;对每一步骤中主要方法的相关原理和应用做了简要介绍与评估;最后总结了当前GICs的研究现状,并对未来GICs的研究方向与挑战进行了展望. 相似文献
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利用第23太阳活动周中WIND和ACE资料,统计分析行星际扰动对不同水平地磁活动的影响,研究磁暴强度与不同行星际参数之间的相关性,结果发现:①从长期来看,地磁活动指数Dst与太阳风速度的相关性最好,相关性在太阳活动谷年时最高;②多磁暴时序叠加结果证实了导致小、中、强磁暴开始的经验行星际南向磁场条件,磁暴过程中行星际磁场... 相似文献
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黄建中 《地震地磁观测与研究》1982,(5)
磁暴是太阳活动与地磁场相互作用所引起的一种复杂的地球物理效应。它们之间的活动相关性已得到了一些定性的了解。例如,据统计分析1937—1959年的580个太阳大耀斑表明,有50％的大耀斑可以引起磁暴。以及太阳黑子数与地磁活动程度(u)之间的11年周期变化等。为了解磁暴与太阳黑子的关系,本文利用太阳黑子相对数与日本柿岗地磁台1948—1978年间(其中所缺的1959—1962年的资料利用鹿屋台资料)每年出现的磁暴数,并 相似文献
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利用我国9个电离层观测站第21和22太阳周大约20年的foF2月中值数据,分析太阳活动和地磁活动对电离层foF2的影响,结果显示白天和夏季夜间foF2和太阳黑子数R之间存在着明显非线性关系,并且随着纬度的降低逐渐增强.当回归分析加入地磁Ap指数时,多重回归模型与实测值误差进一步减小,说明同时考虑太阳活动和地磁活动的非线性影响能够更好地描述foF2的变化.基于foF2与太阳黑子数R及地磁指数Ap之间的非线性统计关系,利用Fourier级数建立9个单站谱模型,并与国际参考电离层IRI进行了比较,精度有一定提高. 相似文献
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2003年10～11月的大磁暴 总被引：3，自引：2，他引：3
分析了引起2003年10～11月发生的3个特大磁暴的太阳活动、行星际扰动以及中国东部地磁台链记录到的地面磁场变化。结果表明,这3个特别大的磁暴是由太阳质量抛射事件引起的。太阳向着地球喷发出的大量等离子体引起的强烈太阳风扰动和持续长时间的南向行星际磁场与磁层相互作用形成了特别大的磁暴。ACE卫星、GOES卫星以及地面地磁台站较完整地记录了这3次日地扰动传输过程。对于每一个磁暴,中国东部地磁台链记录到的H分量变化形态一致,纬度最高的满洲里地磁台H幅度最大,而其他台站的幅度与纬度无明显关系,这表明磁暴的发展不完全由赤道环电流引起,在这样强烈的磁暴期间,磁层内的电流体系非常复杂。 相似文献
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地球自转带动非对等分布的正负电荷绕地轴做圆周运动产生相对于地轴静止的地球主磁场并形成地球电场,同时,由地球自转所带动的带电粒子受到地球电场和地球主磁场的作用.为探索地球气候变化的自然原因,创建相对于地轴静止的地磁参考系,应用经典物理学理论和方法,分析研究大气中带电粒子在地球电场和地球磁场中的运动规律.结果表明:气候带及季节性节律均为大气受到电磁力、热力及地球引力的共同作用而形成;地球电场与地球磁场变化使地球系统带电粒子受到的电磁力发生变化,对气候的影响是全方位的;大气具有一定的自动调节功能,当代气候呈极端化趋势与大气中地球主磁场极弱密切相关.本研究结论概括为四个方面:(1)地球电场使大气中带正、负电荷的粒子呈交错分层分布态势且地球南、北两极及赤道附近空间的电荷密度高.(2)地球主磁场使大气中带正、负电荷的粒子在垂直地球主磁场平面内作方向相反的圆周运动并带动荷电大气回旋形成气旋和反气旋环流.(3)荷电大气回旋规律为:在线速度大小不变条件下回旋半径跟总磁场磁感应强度与大气荷质比的乘积成反比;回旋角速度大小等于总磁场磁感应强度与大气荷质比的乘积,与线速度无关.荷电大气相对于地面的速度在各象限分布不对称.(4)地球电场、地球磁场、荷电大气的运动及其产生的感生电场和感生磁场,遵循麦克斯韦方程组和牛顿运动定律等经典物理学规律,是一个相互纠缠的整体,具有超越介质的遥相关和遥响应机制,能够使大气中的极性分子物质发生电离,地震前地电场和地磁场的异常变化可以在大气中形成地震云.感生电场和感生磁场使回旋的荷电大气作经、纬方向的耦合,形成经、纬方向的偶极子型环流和纬向环状型环流,使荷电大气的运动与地形地势及下垫面的电磁特性紧密相关.荷电大气的回旋具有正反馈机制,随着荷质比的增大能够形成台风、龙卷风等旋风.大气中尺度不同的环流系统,从东(西)风带、南(北)半球环状模,到热带气旋等,都是地球电场和地球磁场驱动的荷电大气的运动所致,准定常行星波是大尺度环流系统感生电磁场传播的结果. 相似文献
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An inspection of the long-term behaviour of the range of the daily geomagnetic field variation from comprehensive modelling 总被引：1，自引：0，他引：1
J. Miquel Torta Luis R. Gaya-Piqu Juan J. Curto David Altadill 《Journal of Atmospheric and Solar》2009,71(13):1497-1510
This paper attempts to reveal whether long-term trends in the ionosphere are reflected in the amplitude range of the geomagnetic daily variation recorded at ground level. The smooth and regular variation observed in the magnetograms on magnetically quiet days is induced by the ionospheric currents flowing in the dynamo region. So it is likely that trends in the conductivity or in the dynamics of this region could produce changes in the current densities, and consequently in the range of the geomagnetic variation. The crucial aspect is how to separate the changes produced by the geomagnetic activity itself, or by secular changes of the Earth's magnetic field, from the part of the variation produced by factors affecting trends in the ionosphere, which could have an anthropogenic origin. To investigate this, we synthesized for several geomagnetic observatories the daily ranges of the geomagnetic field components with a comprehensive model of the quiet-time, near-Earth magnetic field, and finally we removed the synthetic values from the observed ranges at those observatories. This comprehensive model accounts for contributions from Earth's core, lithosphere, ionosphere, magnetosphere and coupling currents, and, additionally, accounts for influences of main field and solar activity variations on the ionosphere. Therefore, any trend remaining in the residuals, assuming that all the contributions mentioned above are properly described and thus removed by the comprehensive model, should reflect the influence of other sources. Results, based on series of magnetic data from observatories worldwide distributed, are presented. Trends in the X and Z components are misleading, since the current system changes in form as well as in intensity, producing changes of the focus latitude in the course of a solar cycle and from one cycle to another. Some differences exist between the long-term trends in the Y component between the real and modelled ranges, suggesting that other non-direct solar causes to the amplitude changes of the solar quiet geomagnetic variation should not be ruled out. Nevertheless, the results also reflect some short-comings in the way that the comprehensive modelling accounts for the influence of the solar activity on the range of the daily geomagnetic variation. 相似文献
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Summary Using the long-term relations between solar motion and solar activity, long-term relations between solar activity and air temperature variations on the Earth's surface have been studied. A long-term periodicity in the period range from 25 to 250 years, corresponding to the periodicity of solar motion and solar activity, has been found in four very long European surface air temperature series. The positions of the spectral peaks approximately obey the relation pi=178.7/i, i=1, 2, ... . Similar long-term patterns of solar and geomagnetic activity and of global surface air temperature have been found in the years 1861 to 1990. The results indicate that the solar activity impact on the climate could be significant, and that the prolonged minimum of solar activity, predicted from solar motion for the next 2 – 3 decades, could decreace global air temperatures. 相似文献
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Summary Using palaeomagnetic investigations of sedimentary rocks and particularly lake sediments, changes of the geomagnetic field and geomagnetic poles were determined over a period of the last 40 000 years. The correlations between geomagnetic, climatic and meteorological phenomena were investigated with the object of demonstrating the function of the geomagnetic pole and changes in its positions in forming the climate and weather. A tentative model has been proposed to enable the causes of the generation of glacial and interglacial periods, as well as the causes effecting changes of weather to be explained. The possibilities of man-made meliorations of the climate in certain regions are also discussed.Presented at the XVI Gen.Assembly IUGG, Grenoble 1975. 相似文献
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Modelling of space weather effects on pipelines 总被引：1，自引：0，他引：1
Antti Pulkkinen Risto Pirjola David Boteler Ari Viljanen Igor Yegorov 《Journal of Applied Geophysics》2001,48(4)
The interaction between the solar wind and the Earth's magnetic field produces time varying currents in the ionosphere and magnetosphere. The currents cause variations of the geomagnetic field at the surface of the earth and induce an electric field which drives currents in oil and gas pipelines and other long conductors. Geomagnetically induced currents (GIC) interfere with electrical surveys of pipelines and possibly contribute to pipeline corrosion.In this paper, we introduce a general method which can be used to determine voltage and current profiles for buried pipelines, when the external geoelectric field and the geometry and electromagnetic properties of the pipeline are known. The method is based on the analogy between pipelines and transmission lines, which makes it possible to use the distributed source transmission line (DSTL) theory. The general equations derived for the current and voltage profiles are applied in special cases. A particular attention is paid to the Finnish natural gas pipeline network.This paper, related to a project about GIC in the Finnish pipeline, thus provides a tool for understanding space weather effects on pipelines. Combined with methods of calculating the geoelectric field during magnetic storms, the results are applicable to forecasting of geomagnetically induced currents and voltages on pipelines in the future. 相似文献
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本文对比分析了太阳活动高、低年期间高纬日侧顶部电离层离子上行随地磁活动水平的变化特征.按地磁活动水平，将DMSP卫星在太阳活动高年（2000-2002年，F13和F15）及太阳活动低年（2007-2009年，F13；2007-2010年，F15）期间的SSIES离子漂移速度观测数据分为三组：地磁平静期（Kp<3），中等地磁扰动期（3 ≤ Kp < 5）和强地磁活动期（Kp ≥ 5），分别统计分析了高纬日侧顶部电离层离子上行特征的时空分布.对比分析发现：（1）太阳活动低年期间，高纬日侧电离层离子上行发生率以及上行速度峰值均是太阳活动高年的2倍多，而离子上行通量峰值只有高年的1/6-1/4；（2）在相同太阳活动条件下，地磁活动水平对日侧电离层离子上行发生率峰值的影响并不明显，但对离子上行发生率的空间分布有着显著的控制作用：电离层离子上行高发区随地磁活动向低纬度扩展，并在强地磁活动期间呈现饱和的趋势；（3）日侧顶部电离层等离子体似乎存在两个效率相当的上行区域，一个位于极尖/极隙区纬度附近，离子可沿开放磁力线上行进入磁尾；另一个位于晨侧亚极光区附近，离子沿闭合磁力线上行，有可能进入日侧等离子体层边界层. 相似文献
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V. A. Dergachev S. S. Vasiliev O. M. Raspopov H. Jungner 《Geomagnetism and Aeronomy》2012,52(8):959-976
Recent studies have shown that, in addition to the role of solar variability, past climate changes may have been connected with variations in the Earth??s magnetic field elements at various timescales. An analysis of variations in geomagnetic field elements, such as field intensity, reversals, and excursions, allowed us to establish a link between climate changes at various timescales over the last millennia. Of particular interest are sharp changes in the geomagnetic field intensity and short reversals of the magnetic poles (excursions). The beginning and termination of the examined geomagnetic excursions can be attributed to periods of climate change. In this study, we analyzed the possible link between short-term geomagnetic variability (jerks) and climate change, as well as the accelerated drift of the north magnetic pole and surface temperature variations. The results do not rule out the possibility that geomagnetic field variations which modulate the cosmic ray flux could have played a major role in climate change in addition to previously induced by solar radiation. 相似文献
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The main features of upper atmosphere dynamics as an important part of upper atmosphere climatology are presented. The dynamics
of the mesosphere and lower thermosphere (MLT) are of special interest. The results are based on the long series of investigations
in East Siberia and data from a world-wide network of observatories. We present the regional climatic norms for the prevailing
wind and semi-diurnal tide and the main features of the quasi-periodic structure of the wind field. The non-zonality of MLT
dynamics is demonstrated as well as regional differences in the response of the wind field to stratospheric disturbances,
solar activity variations and geomagnetic storms. 相似文献
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V. A. Dergachev P. B. Dmitriev O. M. Raspopov H. Jungner 《Geomagnetism and Aeronomy》2007,47(1):109-117
A joint analysis of paleodata on variations in cosmic ray fluxes, solar activity, geomagnetic field, and climate during the period from ～10000 to ～100000 years ago has been performed. Data on the time variations in the concentration of 14C and 10Be cosmogenic isotopes, which are generated in the Earth’s atmosphere under the action of cosmic ray fluxes modulated by solar activity and geomagnetic field variations, were used to detect variations in solar activity and the geomagnetic dipole. Information about climate changes has been obtained mainly from variations in the concentration of stable isotopes in the natural archives. A performed analysis indicates that the variations in cosmic ray fluxes under the action of variations in the geomagnetic field and solar activity are apparently one of the most effective natural factors of long-term climate changeability on a large time scale. 相似文献
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The possible contribution of solar and geomagnetic activity to changes in the characteristics of the main components of the climatic system—the ocean and the atmosphere—is considered and discussed. The mechanisms and models of the solar activity impact on thermobaric and climatic characteristics of the troposphere are presented. Based on a complex analysis of hydrometeorological data, it has been shown that changes in the temperature of the troposphere and the World Ocean reflect a response both to individual helio-geophysical perturbations and to long-term changes (1854–2015) of solar and geomagnetic activity. It is established that the climatic response to the influence of solar and geomagnetic activity is characterized by considerable spatio-temporal heterogeneity, is of a regional nature, and depends on the general circulation of the atmosphere. The largest contribution of solar activity to the global climate changes was observed in the period 1910–1943. 相似文献