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1.
R. A. Nymmik 《Geomagnetism and Aeronomy》2009,49(8):1154-1156
The currently available experimental data, among which the series of particle flux measurements on satellites are of crucial
importance, have revealed a number of regularities pertaining to solar cosmic rays (SCRs). Based on these regularities, we
have developed a probabilistic model of particle fluxes. This model not only provides a basis for determining radiation conditions
in space flights and space weather impacts but also allows such situations as the occurrence of extreme SCR events in the
quiet-Sun period in 2005–2006 to be predicted. 相似文献
2.
《Journal of Atmospheric and Solar》2008,70(15):1870-1878
This paper concentrates on those major areas where our current physical understanding and recent advances can lead to positive predictions of the expected effects of ionospheric activity on the near-Earth space environment and on technological systems which operate within this environment. It briefly describes some of the key links between solar activity and the various physical processes, which govern ionospheric plasma structure that has been under scientific examination over past several decades but has lately received significant importance in relation to the space weather services. Specific examples during extremely intense solar event show how ionospheric monitoring techniques that have contributed immense data sets and related empirical and theoretical formulations have been incorporated in different ionospheric specification and prediction models for real-time operational applications. Finally, the general question of what might be expected as a result of current activities within different European cooperative projects is addressed. 相似文献
3.
4.
Ioannis A. Daglis Georgios Balasis Natalia Ganushkina Fiori-Anastasia Metallinou Minna Palmroth Risto Pirjola Ioanna Tsagouri 《Acta Geophysica》2009,57(1):141-157
Comprehensive understanding of the dynamics of the coupled solar wind-magnetosphere-ionosphere system is of utmost interest,
both from the perspective of solar system astrophysics and geophysics research and from the perspective of space applications.
The physical processes involved in the dynamical evolution of this complex coupled system are pertinent not only for the Sun-Earth
connection, but also for major phenomena in other astrophysical systems. Furthermore, the conditions in geospace collectively
termed space weather affect the ever increasing technological assets of mankind in space and therefore need to be understood,
quantified and efficiently forecasted. The present collaborative paper communicates recent advances in geospace dynamic coupling
research through modeling, simulations and data analysis and discusses future directions. 相似文献
5.
Solar disturbances are observed to have significant effects in near-Earth space. Over the past half-century of observation, a relatively clear picture has developed of how and why the typical solar wind — as well as the most extreme solar events — drive geospace responses. It is clear that magnetospheric substorms, geomagnetic storms (both recurrent and aperiodic events), and even certain atmospheric chemical changes have their origins in the solar–terrestrial coupling arena. High-speed solar wind streams and fast coronal mass ejections (CMEs) can often have strong interplanetary shock waves and southward magnetic fields which can initiate strong storm responses. We demonstrate in this review that available modern space-observing platforms and ground facilities allow us to trace drivers from the Sun to the Earth's atmosphere. This allows us to assess quantitatively the energy transport that occurs throughout the Sun–Earth system during both typical and extreme conditions. Hence, we are continuously improving our understanding of “space weather” and its effects on human society. 相似文献
6.
《Journal of Atmospheric and Solar》2000,62(16):1457-1469
Coronal mass ejections (CMEs) are large-scale magnetized plasma structures ejected from closed magnetic field regions of the Sun. White light coronagraphic observations from ground and space have provided extensive information on CMEs in the outer corona. However, our understanding of the solar origin and early life of CMEs is still in an elementary stage because of lack of adequate observations. Recent space missions such as Yohkoh and Solar and Heliospheric Observatory (SOHO) and ground-based radioheliographs at Nobeyama and Nancay have accumulated a wealth of information on the manifestations of CMEs near the solar surface. We review some of these observations in an attempt to relate them to what we already know about CMEs. Our discussion relies heavily on non-coronagraphic data combined with coronagraphic data. Specifically, we discuss the following aspects of CMEs: (i) coronal dimming and global disk signatures, (ii) non-radial propagation during the early phase, (iii) Photospheric magnetic field changes during CMEs, and (iv) acceleration of fast CMEs. The relative positions and evolution of coronal dimming, arcade formation, prominence eruption will be discussed using specific events. The magnitude and spatial extent of CME acceleration may be an important parameter that distinguishes fast and slow CMEs. 相似文献
7.
《Journal of Atmospheric and Solar》2007,69(12):1305-1311
Geomagnetically induced currents (GIC) flowing in ground-based technological networks, such as electric power transmission grids, are the ground end of the space weather chain originating from the Sun. GIC constitute a possible source of problems to the system. Matrix formulas enabling the calculation of GIC in a power grid have been presented before. In this paper, we summarise the formulas and also express them in an alternative form that includes the (geo)voltages driving GIC during a space weather event more explicitly. An issue usually ignored in GIC modelling is the effect of overhead shield wires protecting a power grid and generally earthed at the towers. By numerical examples, it is shown in this paper that such neglect causes an insignificant error in comparison with other inaccuracies involved in GIC modelling and is thus really acceptable in practice. 相似文献
8.
High-performance computational models are required to make the real-time or faster than real-time numerical prediction of adverse space weather events and their influence on the geospace environment. The main objective in this article is to explore the application of programmable graphic processing units (GPUs) to the numerical space weather modeling for the study of solar wind background that is a crucial part in the numerical space weather modeling. GPU programming is realized for our Solar-Interplanetary-CESE MHD model (SIP-CESE MHD model) by numerically studying the solar corona/interplanetary solar wind. The global solar wind structures are obtained by the established GPU model with the magnetic field synoptic data as input. Meanwhile, the time-dependent solar surface boundary conditions derived from the method of characteristics and the mass flux limit are incorporated to couple the observation and the three-dimensional (3D) MHD model. The simulated evolution of the global structures for two Carrington rotations 2058 and 2062 is compared with solar observations and solar wind measurements from spacecraft near the Earth. The MHD model is also validated by comparison with the standard potential field source surface (PFSS) model. Comparisons show that the MHD results are in good overall agreement with coronal and interplanetary structures, including the size and distribution of coronal holes, the position and shape of the streamer belts, and the transition of the solar wind speeds and magnetic field polarities. 相似文献
9.
We consider the prospects for developing a forecast system for space weather (SPW) parameters with the use of home facilities for groundbased observations of solar activity. The space weather forecast can be conventionally divided into three components: (i) the prediction of recurrent, slowly changing events connected with the topology of the large-scale magnetic field, (ii) the estimation of fluxes of UV and high-energy radiation, and (iii) the observation of high-speed phenomena, such as solar flares and eruption processes, and the prediction of their consequences at the the Earth’s orbit. At present, to predict recurrent events, data from regular observations of the large-scale field of the Sun by the solar telescope–magnetographs for operative (realtime) prediction (STOP) are effectively used. To estimate high-energy fluxes, to register eruption events, and to estimate their geoefficiency, data from the patrol optical telescope–spectrographs may be used. Patrol telescopes operate in automatic mode and register the processes with an interval of approximately one minute. To detect eruption processes, we propose a method based on the difference between the intensity values in the wings of chromospheric spectral lines. The results of the use of the observational complex of the Kislovodsk Mountain Astronomical Station for the SW forecast are considered in the paper. 相似文献
10.
The studies are based on the experimental mass sounding of the interplanetary plasma near the Sun at radial distances of R = 4−70 R
S, performed at Pushchino RAO, Russian Academy of Sciences, and on the calculated magnetic fields in the solar corona based
on the magnetic field strength and structure measured on the Sun’s surface at J. Wilcox Solar Observatory, United States.
The experimental data make it possible to localize the position of the boundary closest to the Sun of the transition transonic
region of the solar wind in the near-solar space (R ≈ 10−20 R
S) and to perform an interrelated study of the solar wind structure and its sources, namely, the magnetic field components
in the solar corona based on these data. An analysis of the evolution of the flow types in 2000–2007 makes it possible to
formulate the physically justified criterion responsible for the time boundaries of different epochs in the solar activity
cycle. 相似文献
11.
With a view to difficulties with explaining the physical mechanism of solar forcing on the Earth’s climate, we applied a new
approach of determining and quantifying an influence of solar-related events on water vapor variability by correlating the
total electron content (TEC) and precipitable water vapor (PWV), both derived from ground-based GPS observations.
In this study, ionospheric TEC and atmospheric PWV values are employed as solar activity and terrestrial climate parameters,
respectively. Three-year GPS data at five stations in Antarctica are analyzed on a daily mean basis. Results show significant
correlation between TEC and PWV differences during storms-affected days. The high correlation between the daily mean values
of TEC and PWV, both of which follow the seasonal signals and subsisting downward trend, suggests an influence of solar activity
on climate variability in Antarctica. These quantities are determined by changes of the upper-atmosphere level, which varies
in conformity with the zenith angle of the Sun. 相似文献
12.
N. Gopalswamy J.M. Davila O.C. St. Cyr E.C. Sittler F. Auchère T.L. Duvall J.T. Hoeksema M. Maksimovic R.J. MacDowall A. Szabo M.R. Collier 《Journal of Atmospheric and Solar》2011,73(5-6):658-663
This paper describes the scientific rationale for an L5 mission and a partial list of key scientific instruments the mission should carry. The L5 vantage point provides an unprecedented view of the solar disturbances and their solar sources that can greatly advance the science behind space weather. A coronagraph and a heliospheric imager at L5 will be able to view CMEs broadsided, so space speed of the Earth-directed CMEs can be measured accurately and their radial structure discerned. In addition, an inner coronal imager and a magnetograph from L5 can give advance information on active regions and coronal holes that will soon rotate on to the solar disk. Radio remote sensing at low frequencies can provide information on shock-driving CMEs, the most dangerous of all CMEs. Coordinated helioseismic measurements from the Sun–Earth line and L5 provide information on the physical conditions at the base of the convection zone, where solar magnetism originates. Finally, in situ measurements at L5 can provide information on the large-scale solar wind structures (corotating interaction regions (CIRs)) heading towards Earth that potentially result in adverse space weather. 相似文献
13.
We analyze variations in the rigidity spectrum of primary cosmic rays during Forbush effects recorded in cycles 20–24 of solar activity on the basis of data from the global network of neutron monitor stations processed by global survey. We investigate variations in the rigidity spectrum index of Forbush effects as a function of the solar activity level, phases of the effect, polarity the total magnetic field of the Sun, type and parameters of the source of cosmic ray modulation, etc. Comprehensive analysis of our results revealed regularities in the dynamics of the energy spectrum of galactic cosmic rays that reflect the dynamic processes occurring in the interplanetary space. 相似文献
14.
《Journal of Atmospheric and Solar》2000,62(14):1223-1232
Space-weather impacts society in diverse ways. Societies’ responses have been correspondingly diverse. Taken together these responses constitute a space weather “enterprise”, which has developed over time and continues to develop. Technological systems that space-weather affects have grown from isolated telegraph systems in the 1840s to ocean and continent-spanning cable communications systems, from a generator electrifying a few city blocks in the 1880s to continent-spanning networks of high-tension lines, from wireless telegraphy in the 1890s to globe-spanning communication by radio and satellites. To have a name for the global totality of technological systems that are vulnerable to space weather, I suggest calling it the cyberelectrosphere. When the cyberelectrosphere was young, scientists who study space weather, engineers who design systems that space weather affects, and operators of such systems — the personnel behind the space-weather enterprise — were relatively isolated. The space-weather enterprise was correspondingly incoherent. Now that the cyberelectrosphere has become pervasive and indispensable to most segments of society, the space weather enterprise has become systematic and coherent. At present it has achieved considerable momentum, but it has barely begun to realize the level of effectiveness to which it can aspire, as evidenced by achievements of a corresponding but more mature enterprise in meteorology, a field which provides useful lessons. The space-weather enterprise will enter a new phase after it matures roughly to where the tropospheric weather enterprise is now. Then it will become indispensable for humankind's further global networking through technology and for humankind's further utilization of and expansion into space. 相似文献
15.
《Journal of Atmospheric and Solar》2002,64(16):1679-1686
The development of new technologies and the miniaturization of sensors bring new requirements for our ability to predict and forecast hazardous space weather conditions. Of particular importance are protons in the energy range from 10s to 100s of MeV which cause electronic part and solar cell degradation, and pose a hazard to biological systems in space and to personnel in polar orbit. Sporadic high-energy solar particle events are a main contributor to the fluences and fluxes of such protons. A statistical model, JPL 1991 (J. Geophys. Res. 98 (1991) 13,281), was developed to specify fluences for spacecraft design and is now widely used. Several major solar proton events have occurred since that model was developed and one objective of this paper is to see if changes need to be made in the model due to these recent events. Another objective is to review the methods used in JPL 1991 in the light of new understandings and to compare the JPL methods with those used in other models. We conclude that the method used in developing JPL 1991 model is valid and that the solar events occurring since then are completely consistent with the 1991 model. Since no changes are needed we suggest that the name of the model be changed to “the JPL fluence model”. 相似文献
16.
Disturbances in the magnetic field and magnetospheric and ionospheric plasma registered on December 14–16, 2006, during a
strong magnetic storm caused by a solar flare of 4B/X3.4 class are studied. It is shown that in the north of Yakutia, interactions between the Earth’s magnetosphere and the region
of high dynamic pressure of the solar wind led to the formation of sporadic layers in the ionospheric E and F regions, depletion of the critical frequency of the F2 layer, and total absorption. At the end of the magnetic storm’s main phase, anomalously high values of foF2 exceeding the quiet level by a factor of 1.5–1.7 were detected. It was found that the disturbances detected by ground-based
observatories had developed on the background of changes in the temperature, density, and the pitch-angle distribution of
particles at the geostationary orbit manifesting radial shifts of magnetospheric structures (magnetopause, cusp/cleft, and
plasma sheet) relative to the observation points. A conclusion is drawn that in this case, changes in the near-Earth plasma
and magnetic field manifest the dynamics of the physical conditions at the magnetospheric boundary and diurnal rotation of
the Earth. 相似文献
17.
地磁扰动是空间天气中的重要现象,对地基技术系统具有重要的影响.准确预报地磁扰动可以有效避免重大灾害发生.本文基于Weimer电势和磁势模型发展了高纬地区地磁扰动的模拟方法,并与地面台站观测数据进行了比较.地表磁场扰动主要受电离层电流系统的影响,利用Weimer模式计算出电离层等效电流分布后,基于毕奥-萨伐尔定律推导了地磁扰动三分量与电流的关系,最终计算出地磁扰动量.模型的输入参数为太阳风速度、太阳风密度、行星际磁场和磁偶极倾角.模型计算结果与不同纬度和经度的地磁台站观测结果对比表明本文的计算方法能有效地模拟地磁暴期间地磁扰动特征.本文结果对今后发展高纬地区地磁场预报模型奠定了重要基础. 相似文献
18.
We use the theory of continuous-time Markov chains (CTMCs) to analyze hitherto unstudied questions about jointly determined
ecological–economic systems. Two specific questions are examined. First, on the methodological front, we show how the theory
of CTMCs can be used to effectively model dynamic and stochastic ecological–economic systems. Then, given recent concern about
the sustainability of desirable states and lock-in into undesirable states, we partition the state space of our stylized ecological–economic
system into good and bad states, and demonstrate the formal relationship between these two sets of states. Second, we discuss
a way of looking at the task of managing ecological–economic systems that captures this formal link between the good and the
bad states, and has other desirable properties. 相似文献
19.
Geomagnetism and Aeronomy - The dynamics of the areas of coronal holes and their localization on the Sun in solar cycle 24 and the minimum of cycles 24–25 were analyzed. The study is based on... 相似文献
20.
Meng Zhiyong Zhang Fuqing Luo Dehai Tan Zhemin Fang Juan Sun Jianhua Shen Xueshun Zhang Yunji Wang Shuguang Han Wei Zhao Kun Zhu Lei Hu Yongyun Xue Huiwen Ma Yaping Zhang Lijuan Nie Ji Zhou Ruilin Li Sa Liu Hongjun Zhu Yuning 《中国科学:地球科学(英文版)》2019,62(12):1946-1991
Synoptic meteorology is a branch of meteorology that uses synoptic weather observations and charts for the diagnosis,study,and forecasting of weather.Weather refers to the specific state of the atmosphere near the Earth's surface during a short period of time.The spatial distribution of meteorological elements in the atmosphere can be represented by a variety of transient weather phenomena,which are caused by weather systems of different spatial and temporal scales.Weather is closely related to people's life,and its development and evolution have always been the focus of atmospheric scientific research and operation.The development of synoptic meteorology is closely related to the development of observation systems,dynamical theories and numerical models.In China,observation networks have been built since the early 1950 s.Up to now,a comprehensive meteorological observation systembased on ground,air and space has been established.In particular,the development of a new generation of dense radar networks,the development of the Fengyun satellite series and the implementation of a series of large field experiments have brought our understanding of weather from large-scale environment to thermal dynamics,cloud microphysical structure and evolution characteristics of meso and micro-scale weather systems.The development of observation has also promoted the development of theory,numerical model and simulation.In the early days,China mainly used foreign numerical models.Lately,China has developed numerical model systems with independent intellectual property rights.Based on the results of high-resolution numerical simulations,in-depth understanding of the initiation and evolution mechanism and predictability of weather at different scales has been obtained.Synoptic meteorology has gradually changed from an initially independent development to a multidisciplinary approach,and the interaction between weather and the change of climate and environment has become a hot and frontier topic in atmospheric science.This paper reviews the important scientific and technological achievements made in China over the past 70 years in the fields of synoptic meteorology based on the literatures in China and abroad,from six aspects respectively including atmospheric dynamics,synoptic-scale weather,typhoon and tropical weather,severe convective weather,numerical weather prediction and data assimilation,weather and climate,atmospheric physics and atmospheric environment. 相似文献