scholarly journals April 2000 geomagnetic storm: ionospheric drivers of large geomagnetically induced currents

2003 ◽  
Vol 21 (3) ◽  
pp. 709-717 ◽  
Author(s):  
A. Pulkkinen ◽  
A. Thomson ◽  
E. Clarke ◽  
A. McKay
Keyword(s):  
Geomagnetic Storm ◽  
Large Scale ◽  
Regional Scale ◽  
Normal Operation ◽  
Technological Systems ◽  
Geomagnetically Induced Currents ◽  
Ionospheric Currents ◽  
Ionospheric Current ◽  
Induced Currents ◽  
Current Systems

Abstract. Geomagnetically induced currents (GIC) flowing in technological systems on the ground are a direct manifestation of space weather. Due to the proximity of very dynamic ionospheric current systems, GIC are of special interest at high latitudes, where they have been known to cause problems, for example, for normal operation of power transmission systems and buried pipelines. The basic physics underlying GIC, i.e. the magnetosphere – ionosphere interaction and electromagnetic induction in the ground, is already quite well known. However, no detailed study of the drivers of GIC has been carried out and little is known about the relative importance of different types of ionospheric current systems in terms of large GIC. In this study, the geomagnetic storm of 6–7 April 2000 is investigated. During this event, large GIC were measured in technological systems, both in Finland and in Great Britain. Therefore, this provides a basis for a detailed GIC study over a relatively large regional scale. By using GIC data and corresponding geomagnetic data from north European magnetometer networks, the ionospheric drivers of large GIC during the event were identified and analysed. Although most of the peak GIC during the storm were clearly related to substorm intensifications, there were no common characteristics discernible in substorm behaviour that could be associated with all the GIC peaks. For example, both very localized ionospheric currents structures, as well as relatively large-scale propagating structures were observed during the peaks in GIC. Only during the storm sudden commencement at the beginning of the event were large-scale GIC evident across northern Europe with coherent behaviour. The typical duration of peaks in GIC was also quite short, varying between 2–15 min.Key words. Geomagnetism and paleo-magnetism (geomagnetic induction) – Ionosphere (ionospheric disturbances) – Magnetospheric physics (storms and substorms)

scholarly journals Regional-scale high-latitude extreme geoelectric fields pertaining to geomagnetically induced currents

2015 ◽  
Vol 67 (1) ◽  
Author(s):  
Antti Pulkkinen ◽  
Emanuel Bernabeu ◽  
Jan Eichner ◽  
Ari Viljanen ◽  
Chigomezyo Ngwira
Keyword(s):  
High Latitude ◽  
Regional Scale ◽  
Geomagnetically Induced Currents ◽  
Induced Currents

Intense dB/dt variations driven by near-Earth Bursty Bulk Flows (BBFs): A case study

2021 ◽  
Author(s):  
Dong Wei ◽  
Malcolm Dunlop ◽  
Junying Yang ◽  
Xiangcheng Dong ◽  
Yiqun Yu ◽  
...  
Keyword(s):  
Large Scale ◽  
Current System ◽  
Geomagnetically Induced Currents ◽  
Inner Magnetosphere ◽  
Wide Range ◽  
Ground System ◽  
Induced Currents ◽  
Ground Magnetic ◽  
Bursty Bulk Flows

<p>During geomagnetically disturbed times the surface geomagnetic field often changes abruptly, producing geomagnetically induced currents (GICs) in a number of ground based systems. There are, however, few studies reporting GIC effects which are driven directly by bursty bulk flows (BBFs) in the inner magnetosphere. In this study, we investigate the characteristics and responses of the magnetosphere-ionosphere-ground system during the 7 January 2015 storm by using a multi-point approach which combines space-borne measurements and ground magnetic observations. During the event, multiple BBFs are detected in the inner magnetosphere while the magnetic footprints of both magnetospheric and ionospheric satellites map to the same conjugate region surrounded by a group of magnetometer ground stations. It is suggested that the observed, localized substorm currents are caused by the observed magnetospheric BBFs, giving rise to intense geomagnetic perturbations. Our results provide direct evidence that the wide-range of intense dB/dt<strong> </strong>(and dH/dt) variations are associated with a large-scale, substorm current system, driven by multiple BBFs.</p>

scholarly journals Evaluation of the geometry of ionospheric current systems related to rapid geomagnetic variations

2004 ◽  
Vol 22 (1) ◽  
pp. 63-72 ◽  
Author(s):  
S. V. Apatenkov ◽  
V. A. Sergeev ◽  
R. Pirjola ◽  
A. Viljanen
Keyword(s):  
Dynamic Pressure ◽  
Auroral Oval ◽  
Auroral Zone ◽  
Middle Part ◽  
Magnetic Storms ◽  
Geomagnetically Induced Currents ◽  
Geomagnetic Variations ◽  
Ionospheric Current ◽  
Solar Wind Parameters ◽  
Current Systems

Abstract. To learn about the geometry and sources of the ionospheric current systems which generate strong geomagnetically induced currents, we categorize differential equivalent current systems (DEC) for events with strong dB/dt by decomposing them into the contributions of electrojet-type and vortex-type elementary systems. By solving the inverse problem we obtain amplitudes and locations of these elementary current systems. One-minute differences of the geomagnetic field values at the IMAGE magnetometer network in 1996–2000 are analysed to study the spatial distributions of large dB/dt events. The relative contributions of the two components are evaluated. In particular, we found that the majority of the strongest dB/dt events (100–1000nT/min) appear to be produced by the vortex-type current structures and most of them occur in the morning LT hours, probably caused by the Ps6 pulsation events associated with auroral omega structures. For strong dB/dt events the solar wind parameters are shifted toward strong (tens nT) southward IMF, enhanced velocity and dynamic pressure, in order for the main phase of the magnetic storms to occur. Although these events appear mostly during magnetic storms when the auroral oval greatly expands, the area of large dB/dt stays in the middle part of the auroral zone; therefore, it is connected to the processes taking part in the middle of the magnetosphere rather than in its innermost region populated by the ring current. Key words. Geomagnetism and paleomagnetism (rapid time variations) – Ionosphere (auroral ionosphere; ionospheric disturbances)

scholarly journals Impulsive disturbances of the geomagnetic field as a cause of induced currents of electric power lines

2019 ◽  
Vol 9 ◽  
pp. A18 ◽  
Author(s):  
Vladimir Belakhovsky ◽  
Vyacheslav Pilipenko ◽  
Mark Engebretson ◽  
Yaroslav Sakharov ◽  
Vasily Selivanov
Keyword(s):  
Electric Power ◽  
Transmission Lines ◽  
Geomagnetic Field ◽  
Energy Yield ◽  
Interplanetary Shocks ◽  
Geomagnetically Induced Currents ◽  
Ionospheric Currents ◽  
Geomagnetic Variations ◽  
Electric Power Line ◽  
Induced Currents

Geomagnetically induced currents (GICs) represent a significant challenge for society on a stable electricity supply. Space weather activates global electromagnetic and plasma processes in the near-Earth environment, however, the highest risk of GICs is related not directly to those processes with enormous energy yield, but too much weaker, but fast, processes. Here we consider several typical examples of such fast processes and their impact on power transmission lines in the Kola Peninsula and in Karelia: interplanetary shocks; traveling convection vortices; impulses embedded in substorms; and irregular Pi3 pulsations. Geomagnetic field variability is examined using data from the IMAGE (International Monitor for Auroral Geomagnetic Effects) magnetometer array. We have confirmed that during the considered impulsive events the ionospheric currents fluctuate in both the East-West and North-South directions, and they do induce GIC in latitudinally extended electric power line. It is important to reveal the fine structure of fast geomagnetic variations during storms and substorms not only for a practical point of view but also for a fundamental scientific view.

scholarly journals Quantitative influence of coast effect on geomagnetically induced currents in power grids: a case study

2018 ◽  
Vol 8 ◽  
pp. A60 ◽  
Author(s):  
Chunming Liu ◽  
Xuan Wang ◽  
Hongmei Wang ◽  
Huilun Zhao
Keyword(s):  
Three Dimensional ◽  
Power Grids ◽  
Normal Operation ◽  
Power Networks ◽  
Geomagnetically Induced Currents ◽  
Coast Effect ◽  
1D Model ◽  
Coastal Effect ◽  
Induced Currents ◽  
Earth Conductivity

In recent years, several magnetic storms have disrupted the normal operation of power grids in the mid-low latitudes. Data obtained from the monitoring of geomagnetically induced currents (GIC) indicate that GIC tend to be elevated at nodes near the ocean-land interface. This paper discusses the influence of the geomagnetic coast effect on GIC in power grids based on geomagnetic data from a coastal power station on November 9, 2004. We used a three-dimensional (3D) Earth conductivity model to calculate the induced electric field using the finite element method (FEM), and compared it to a one-dimensional (1D) layered model, which could not incorporate a coastal effect. In this manner, the GIC in the Ling’ao power plant was predicted while taking the coast effect into consideration in one case and ignoring it in the other. We found that the GIC predicted by the 3D model, which took the coastal effect into consideration, showed only a 2.9% discrepancy with the recorded value, while the 1D model underestimated the GIC by 23%. Our results demonstrate that the abrupt lateral variations of Earth conductivity structures significantly influence GIC in the power grid. We can infer that high GIC may appear even at mid-low latitude areas that are subjected to the coast effect. Therefore, this effect should be taken into consideration while assessing GIC risk when power networks are located in areas with lateral shifts in Earth conductivity structures, such as the shoreline and the interfaces of different geological structures.

scholarly journals Induced currents due to 3D ground conductivity play a major role in the interpretation of geomagnetic variations

2020 ◽  
Vol 38 (5) ◽  
pp. 983-998
Author(s):  
Liisa Juusola ◽  
Heikki Vanhamäki ◽  
Ari Viljanen ◽  
Maxim Smirnov
Keyword(s):  
Magnetic Field ◽  
Electric Fields ◽  
Time Derivative ◽  
Three Dimensional ◽  
Geomagnetically Induced Currents ◽  
Ionospheric Currents ◽  
Geomagnetic Variations ◽  
Near Surface ◽  
Induced Currents ◽  
Telluric Currents

Abstract. Geomagnetically induced currents (GICs) are directly described by ground electric fields, but estimating them is time-consuming and requires knowledge of the ionospheric currents and the three-dimensional (3D) distribution of the electrical conductivity of the Earth. The time derivative of the horizontal component of the ground magnetic field (dH∕dt) is closely related to the electric field via Faraday's law and provides a convenient proxy for the GIC risk. However, forecasting dH∕dt still remains a challenge. We use 25 years of 10 s data from the northern European International Monitor for Auroral Geomagnetic Effects (IMAGE) magnetometer network to show that part of this problem stems from the fact that, instead of the primary ionospheric currents, the measured dH∕dt is dominated by the signature from the secondary induced telluric currents at nearly all IMAGE stations. The largest effects due to telluric currents occur at coastal sites close to high-conducting ocean water and close to near-surface conductivity anomalies. The secondary magnetic field contribution to the total field is a few tens of percent, in accordance with earlier studies. Our results have been derived using IMAGE data and are thus only valid for the stations involved. However, it is likely that the main principle also applies to other areas. Consequently, it is recommended that the field separation into internal (telluric) and external (ionospheric and magnetospheric) parts is performed whenever feasible (i.e., a dense observation network is available).

scholarly journals Geomagnetically induced pipe-to-soil voltages in the Czech oil pipelines during October-November 2003

2005 ◽  
Vol 23 (9) ◽  
pp. 3089-3093 ◽  
Author(s):  
P. Hejda ◽  
J. Bochníček
Keyword(s):  
Czech Republic ◽  
Geomagnetic Field ◽  
Earth Model ◽  
Technological Systems ◽  
Geomagnetically Induced Currents ◽  
Geomagnetic Disturbances ◽  
The Czech Republic ◽  
Soil P ◽  
Oil Pipelines ◽  
Induced Currents

Abstract. Whereas geomagnetically induced currents are a source of problems for technological systems mainly at high geomagnetic latitudes, strong geomagnetic disturbances can have quite strong effects even at mid-latitudes. This paper deals with the analysis of the pipe-to-soil (P/S) voltage measured in oil pipelines in the Czech Republic during the Halloween magnetic storms in 2003. It is shown that the simplest - plane wave and uniform Earth-model of the electric field corresponds well to the measured P/S voltage. Although the largest amplitudes of the geomagnetic field were reached on the onset of the geomagnetic storm, large voltages were also induced in the main and recovery phases due to Pc5 oscillations.

Worldwide distribution of geomagnetic tides

1973 ◽  
Vol 274 (1243) ◽  
pp. 551-594 ◽  
Keyword(s):  
Spherical Harmonic ◽  
Large Scale ◽  
Spherical Harmonic Analysis ◽  
Geomagnetic Variation ◽  
Mean Values ◽  
Ionospheric Dynamo ◽  
Worldwide Distribution ◽  
Induced Currents ◽  
Dynamo Effect ◽  
Current Systems

Geomagnetic lunar-daily variations result from the Moon’s tidal action on the ionosphere and oceans. They provide information that bears on the general large-scale dynamics of the atmosphere, and can also add to our understanding of ionospheric processes. For these reasons the variations, though small, are worth determining from geomagnetic data. The data for this study are hourly mean values of the geomagnetic elements from 100 observatories for the interval 1957.5 to 1960.0. These are analysed by the Chapman-Miller method to obtain parameters of the principal lunar harmonics. For each observatory, the contribution of the sea tidal dynamo to these parameters is empirically determined; this contribution has been ignored in previous worldwide studies, but is shown here to be an appreciable proportion of the total lunar effect, and worthy of study in its own right. After removal of the ocean dynamo effect, the remaining geomagnetic lunar daily variation, ascribed to the ionospheric dynamo and its associated induced currents, is represented by a series of spherical harmonic coefficients, and separated into parts of internal and external origin. (In this context, the relative merits of spherical harmonic analysis and the Price-Wilkins method of analysis are discussed.) Internal and external current systems associated with the ionospheric dynamo effect are deduced. Similar analyses, for the solar daily geomagnetic variation and for the lunar semidiurnal tide in the atmospheric pressure, are appended.

Sign in / Sign up

Export Citation Format

Share Document