Horizontal Component Of Geomagnetic Field Research Articles

Пространственное распределение авроральных высыпаний и сбоев в работе железнодорожной автоматики на севере европейской части России

We study the relationship between space weather disturbances and spatial distribution of failures in railway automatics at segments of Northern and October railways in 2001–2006. During the most intensive magnetic storms that caused numerous failures, latitude distribution of auroral electron precipitation and local geomagnetic disturbance, determined as mean absolute value of time derivative of the geomagnetic field horizontal component |dBH/dt|, are examined. We show that in magnetic storm main and recovery phases the segments, where the failures were recorded, correspond to the region of intense auroral precipitation and |dBH/dt| exceeded 5 nT/s. The relationship between position of auroral oval equatorial boundary and spatial distribution of failures is analyzed for individual magnetic storms and statistically for five years of observations. Both individual cases and statistic tests show that southward displacement of the auroral oval equatorial boundary correlates with increase in the proportion of failures at lower latitude railway segments.

Spatial distribution of auroral precipitation and failures in railway automatics at the north of European Russia

We study the relationship between space weather disturbances and spatial distribution of failures in railway automatics at segments of Northern and October railways in 2001–2006. During the most intensive magnetic storms that caused numerous failures, latitude distribution of auroral electron precipitation and local geomagnetic disturbance, determined as mean absolute value of time derivative of the geomagnetic field horizontal component |dBH/dt|, are examined. We show that in magnetic storm main and recovery phases the segments, where the failures were recorded, correspond to the region of intense auroral precipitation and |dBH/dt| exceeded 5 nT/s. The relationship between position of auroral oval equatorial boundary and spatial distribution of failures is analyzed for individual magnetic storms and statistically for five years of observations. Both individual cases and statistic tests show that southward displacement of the auroral oval equatorial boundary correlates with increase in the proportion of failures at lower latitude railway segments.

Variation of Total Electron Content over Nepal during Geomagnetic Storms: GPS Observations

Geomagnetic storms have very profound effects on the Total Electron Content (TEC) of the ionosphere. In order to investigate the equatorial and low-latitude ionospheric response to the geomagnetic storms of varying intensities, a detailed study of vertical TEC (VTEC) variations resulting from Global Positioning System (GPS) data acquired at four GPS stations in Nepal along 80°–90° E longitude and 26°–30° N latitude sector has been carried out in the present work. The results were analyzed with other favorable inducing factors (solar wind parameters and geomagnetic indices) affecting TEC to constrain the causative factor. Positive phases are observed for all the storms studied. During the severe geomagnetic activity, the deviation was ~18 TECU, while it was recorded ~12 TECU and ~8 TECU during moderate and minor geomagnetic activity, respectively. The Detrended Cross-Correlation Analysis (DXA) illustrates that the value of the hourly average VTEC of the BESI station was found to have a strong positive correlation with other stations in all types of storm events, indicating a similar response of all stations towards the space weather events. In addition, the correlation of VTEC with solar wind parameters and geomagnetic indices illustrated that the VTEC shows a strong positive association with solar wind velocity (Vsw) in all three geomagnetic events. In contrast, the correlation of plasma density (Nsw), interplanetary magnetic field (IMF-Bz), the symmetric horizontal component of geomagnetic field (SYM-H), and Geomagnetic Auroral Electrojet (AE) index with VTEC vary with the intensity of the storm. Overall results of the study have revealed the characteristic features of TEC variation over Nepal regions during magnetic storms, which validates earlier research on ionospheric responses to geomagnetic storms and theoretical assumptions.

Disturbances in the geomagnetic field, water level and atmospheric pressure associated with Mw ≥ 6.6 earthquakes in the South Atlantic Ocean

This paper is aimed at studying disturbances in the earth’s geomagnetic field (GMF), water level (WL) and sea-level atmospheric pressure (AP) associated with Mw≥ 6.6 seismic events in the in the Scotia arch, in the South Atlantic. GMF records from observatories of the International Magnetic Observatory Network (INTERMAGNET), WL records from tide stations of the Intergovernmental Oceanographic Commission, and hourly AP records from databases of the Global Modeling and Assimilation Office of the National Aeronautics and Space Administration have been analyzed in the area under study. For the analysis of geomagnetic disturbances, the GMF horizontal component (H), which is more susceptible to variations, was considered. For the WL analysis, the discrepancy (residue) between the WL time series from tide stations and the predicted level of astronomical tides, for a 10-day period before and after the occurrence of each earthquake, was calculated. For the AP analysis, the variation of data gridded between 1 and 2 hours before and after the earthquake was calculated. The analysis of the geomagnetic data prior to the seismic event, using a high-pass filter and the wavelet method, showed: a) high energy ranges in all frequencies, even in very high ones; and b) oscillations in the filter with amplitude peaks of ± 0.2 nT, and with an anticipation and duration consistent with the wavelet method. As regards the WL residues calculated, there were oscillations in the largest amplitudes in the sensors located closest to the earthquake, thus, those large amplitudes corresponded to shorter times of arrival. The AP study showed a maximum followed by a local minimum within a range of ± 0.3 hPa around the location of the earthquake. While the GMF analysis anticipated seismic events within a range of 6-2 hours, the techniques used for WL and AP could detect Mw>7 earthquakes, associating them with the rising/falling surface of the sea. These three techniques can be used jointly to implement a prevention or early warning system for seismic events in the region under study.

Ionospheric irregularities observed during the geomagnetic storm of March 2015 and June 2015 over Ethiopia

Ionospheric irregularities observed during the geomagnetic storm of March 2015 and June 2015 over Ethiopia

Assessment of Geomagnetically Induced Currents in Low Latitude Regions with respect to Severe Geomagnetic Storm over Solar Cycle 24

Space Weather Perturbation – driven Geomagnetically Induced Currents (GIC) can cause the adverse impact to series of ground technological instruments. Power networks are the most affected technological facilities that experience malfunctions due to GIC phenomenon. High latitude regions experience more power network operation flaws due to this natural threat compared to mid latitude and low latitude regions. However different event of solar activities exhibit different space weather perturbations impacts regionally. Therefore, in this study, a thorough analysis of GIC activities during 6 severe geomagnetic storms in low latitude regions over solar cycle 24 based on Time Derivative of Horizontal Component of Geomagnetic Field (dH/dt) analysis are conducted. The results revealed that there is non-uniform latitudinal distribution of averaged dH/dt value in low latitude region and high GIC occurrences are observed during dayside. The correlation analysis between Solar Wind Parameters and GIC activities depicted that solar wind dynamic pressure (Psw) and Solar wind input energy (ε) act as Solar wind driver for the occurrences of GIC in low latitude region.

Estimating the daytime vertical E × B drift velocities in the F-region of the equatorial ionosphere using the IEEY and AMBER magnetic data in West Africa

Estimating the daytime vertical E × B drift velocities in the F-region of the equatorial ionosphere using the IEEY and AMBER magnetic data in West Africa

Low-frequency oscillations while magnetic storms as a tool to determine the types of solar plasma flows

Comparison of wavelet spectrum (skeletons) local maxima for disturbed components of solar plasma flow parameters and geomagnetic field disturbances recorded along the meridional station chain during geomagnetic storm intervals is performed in the range of magnetohydrodynamic (MHD) waves. An algorithm for quantitative evaluation of analyzed skeletons consistency has been developed. It has been used to demonstrate the possibility of the type of solar wind plasma flow elaboration on unique spectral signs of Solar wind speed disturbances, density and interplanetary magnetic field. It is shown that the energy spectrum of oscillations for these parameters reflects the internal structure of the corresponding plasma formation. The skeletons application to the analysis of the interplanetary space main parameters made it possible to estimate the magnetosphere reaction time in geomagnetic field horizontal component oscillations at different latitudes on the disturbance. As a result, the distributed magnetosphere reaction over latitude was determined in the form of geomagnetic field oscillations on the disturbed solar flow parameters. It is shown that the dynamics of the components of the solar wind parameters disturbance spectra corresponding to plasma flows manifest themselves in the MHD spectra of high-latitude stations magnetograms and can be used as a diagnostic tool.

Variation of Solar Wind Parameters Along With the Understanding of Energy Dynamics Within the Magnetospheric System During Geomagnetic Disturbances

AbstractInterplanetary solar wind parameters (velocity of solar wind particle [Vp], proton density [Nsw], and component of solar magnetic field [IMF‐Bz]) and geomagnetic indices (symmetric horizontal component of geomagnetic field [SYM‐H], auroral electrojet [AE]) divulge great deal of information about geomagnetic disturbances. To better understand the influence of solar wind invasion into the energy dynamics of magnetosphere system, we have chosen five geomagnetic disturbance events of completely different nature as the quietest days, intense storm, High Intensity Long Duration Continuous Auroral Activity, Substorm, and Supersubstorm. The statistical analysis of these five events clearly supports the case that most of the time IMF‐Bz plays major role to create magnetic reconnection leading to the geomagnetic disturbances. Our study shows that Joule heating covers the largest fraction of energy dissipation, averaging 53.6% of total deposited energy for all events. Even though, in case of Supersubstorm, the major contribution due to the ring current (47%) surpasses Joule heating (43%). The cross‐correlation analysis applied for the IMF‐Bz with SYM‐H, solar wind energy and magnetospheric sinks explain and quantify the relation between them. The positive correlation of IMF‐Bz with SYM‐H value in each event delineates that southward orientation of IMF‐Bz is responsible for the depression of SYM‐H. However, an interesting result that IMF‐Bz correlated negatively with SYM‐H value for the quiet event suggests the southward orientation of IMF‐Bz does not necessarily have to be the cause of disturbance always. In few occasion, Solar Quiet (Sq) and Lunar (L) current is found to be taking over the role of IMF‐Bz to create disturbance.

The first solar-powered Magdas-9 installation and possible geomagnetically induced currents study at Johor, Malaysia

The Magnetic Data Acquisition System (MAGDAS-9) was successfully installed at Universiti Teknologi MARA Johor, Pasir Gudang Campus, Malaysia (JOH station), under the joint collaboration between International Center for Space Weather Science and Education (ICSWSE), National Space Agency (ANGKASA) and UiTM Johor. This is the first solar-powered magnetometer under the Magnetic Data Acquisition System of Circum-pan Pacific Magnetometer Network (MAGDAS/CPMN). In this paper, construction process, installation process and analysis of first geomagnetic observations at MAGDAS JOH station are presented. In addition, analysis on time derivative of horizontal component of geomagnetic field (dH/dt) to indicate the possibility of Geomagnetically Induced Currents (GIC) occurrences is also presented in this paper. The obtained geomagnetic components: H, D, Z and Total F are approximately similar to World Magnetic Model 2015 (WMM2015) while the diurnal variation from this geomagnetic observation showing a good variation pattern. The analysis of dH/dt has indicated 2 significant events of GIC.

Classification of Solar Plasma Flows by Analyzing Out- and Intra-Magnetospheric Magnetohydrodynamic Oscillations During Magnetic Storms

Comparison of wavelet spectrum (skeletons) local maxima for disturbed components of solar plasma flow parameters and geomagnetic field disturbances recorded along the meridional station chain during geomagnetic storm intervals is performed in the range of magnetohydrodynamic (MHD) waves. An algorithm for quantitative evaluation of analyzed skeletons consistency has been developed. It has been used to demonstrate the possibility of the type of solar wind plasma flow elaboration on unique spectral signs of Solar wind speed disturbances, density and interplanetary magnetic field. It is shown that the energy spectrum of oscillations for these parameters reflects the internal structure of the corresponding plasma formation. The skeletons application to the analysis of the interplanetary space main parameters made it possible to estimate the magnetosphere reaction time in geomagnetic field horizontal component oscillations at different latitudes on the disturbance. As a result, the distributed magnetosphere reaction over latitude was determined in the form of geomagnetic field oscillations on the disturbed solar flow parameters. It is shown that the dynamics of the components of the solar wind parameters disturbance spectra corresponding to plasma flows manifest themselves in the MHD spectra of high-latitude stations magnetograms and can be used as a diagnostic tool.

Spectral characteristic of geomagnetically induced current during geomagnetic storms by wavelet techniques

Spectral characteristic of geomagnetically induced current during geomagnetic storms by wavelet techniques

Ground-Based Observations of Powerful Solar Flares Precursors

AbstractThe opportunity of development the short-term forecasting technique of geoeffective solar flares is presented in this study. This technique is based on the effect of growth the fluctuations of horizontal component of geomagnetic field before the solar proton flares, that is considered as a prognostic parameter of solar proton flares.

Solar and lunar tidal variabilities in GPS‐TEC and geomagnetic field variations: Seasonal as well as during the sudden stratospheric warming of 2010

AbstractThe Global Positioning System (GPS) deduced total electron content (TEC) data at 15°N (geomagnetic), which is the northern crest region of equatorial ionization anomaly, are used to study solar and lunar tidal variabilities during the years 2008 and 2009 and also during the 2009–2010 winter, when a major sudden stratospheric warming (SSW) event has occurred. The diurnal and semidiurnal tidal amplitudes show semiannual variation with maximum amplitudes during February–March and September–November, whereas terdiurnal tide is larger during April–September. They show significant longitudinal variability with larger (smaller) amplitudes over 250°E–150°E (200°E–250°E). Lunar semidiurnal tidal amplitudes show sporadic enhancements during northern winter months and negligible amplitudes during northern summer months. They also show notable longitudinal variabilities. The solar migrating tides DW1 and SW2 show semiannual variation with larger amplitudes during spring equinox months, whereas TW3 maximizes during northern summer. DW2 shows larger amplitudes during summer months. During the SSW, except TW3, the migrating tides DW1 and SW2 show considerable enhancements. Among solar nonmigrating tides, SW1, TW2, and DS0 show larger enhancements. Solar tides in TEC and equatorial electrojet strength over Tirunelveli vary with the time scale of 60 days during October 2009–March 2010 similar to ozone mass mixing ratio at 10 hPa, and this confirms the vital role of ozone in tidal variabilities in ionospheric parameters. Lunar tidal amplitudes in changes in horizontal component of geomagnetic field (ΔH) are larger over Tirunelveli, a station near dip equator. Solar semidiurnal tides in ΔH have larger amplitudes than lunar tides over polar stations, Mawson and Godhavn.

Influence of geomagnetic activity and atmospheric pressure in hypertensive adults.

We performed a study of the systolic and diastolic arterial blood pressure behavior under natural variables such as the atmospheric pressure and the horizontal geomagnetic field component. We worked with a group of eight adult hypertensive volunteers, four men and four women, with ages between 18 and 27years in Mexico City during a geomagnetic storm in 2014. The data was divided by gender, age, and day/night cycle. We studied the time series using three methods: correlations, bivariate analysis, and superposed epoch (within a window of 2days around the day of occurrence of a geomagnetic storm) analysis, between the systolic and diastolic blood pressure and the natural variables. The correlation analysis indicated a correlation between the systolic and diastolic blood pressure and the atmospheric pressure and the horizontal geomagnetic field component, being the largest during the night. Furthermore, the correlation and bivariate analyses showed that the largest correlations are between the systolic and diastolic blood pressure and the horizontal geomagnetic field component. Finally, the superposed epoch analysis showed that the largest number of significant changes in the blood pressure under the influence of geomagnetic field occurred in the systolic blood pressure for men.

Quiet Time Correlation Between Geomagnetic Field Variations and the Dynamics of the East African Equatorial Ionosphere

The equatorial ionosphere is highly dynamic and consequently poses serious threats to communication and navigation systems. As a result, proper understanding of ionospheric dynamics is important. The present paper presents the results of an investigation of the correlation between quiet time vertical total electron content (VTEC) and solar quiet variation in the horizontal component of geomagnetic field (Sq(H)) from low solar activity year (2009) to the high solar activity year (2014) within the equatorial East African sector using statistical analysis method. Values of Sq(H) were observed to increase steadily from around 0700LT attaining maximum values around 1100-1200LT, then descending towards zero level and beyond. The magnitudes of (VTEC) increase uniformly from around 0600-1000LT, then gradually, attaining maximum values around 1300-1500LT. The time instants of occurrence of these peaks are mainly controlled by drifts and photo-ionization. The correlation coefficients (ccs) between (VTEC) and Sq(H) were found to be strongest during the ascending phase (0600-1200LT), ranging from 0.69 to 0.98 at Addis Ababa and 0.61 to 0.97 at Nairobi. During the descending phase (1300-1800LT), ccs range from -0.28 to 0.89 at Addis Ababa and-0.06 to 0.76 at Nairobi. A high level of significance (99.98%) of ccs was obtained. The good linear relationship is attributed to the independent increase of the eastward electric field and photo-ionization on (VTEC) while poor relationship is possibly due to domination of photo-ionization over equatorial ionization anomaly (EIA) development. The annual ccs between (VTEC) and Sq(H) exhibit a general dependence on solar activity at Addis Ababa, closer to the dip equator, rather than at Nairobi during the ascending phase of the daytime. This observation suggests that the EEJ changes linearly with change in solar activity, thus streamlining the variations in TEC, through drifts, and Sq(H) by intensifying the eastward equatorial electric field.

The First Documented Space Weather Event That Perturbed the Communication Networks in Iberia

AbstractIn this work, we review the first space weather event that affected significantly a number of communication networks in the Iberian Peninsula (Southwest of Europe). The event took place on 31 October 1903, during the ascending phase of solar cycle 14 (the lowest since the Dalton Minimum). We describe the widespread problems that occurred in the telegraph communication network in two midlatitude countries (Portugal and Spain), that was practically interrupted from 09 h30 to 21 h00 UT. Different impacts on the telegraphic communication are described and shown to be dependent on the large‐scale orientation of the wires. In order to put these results into a wider context we provide measurements of the concurrent geomagnetic field that are available from the observatories of Coimbra (Portugal) and San Fernando (Spain). The measurements confirm the simultaneous occurrence of large geomagnetic disturbances. In particular, the magnetograms recorded in Coimbra show a clear and large amplitude storm sudden commencement around 05 h30. The main phase, with a H (horizontal component of geomagnetic field) maximum range of ~500 nT, started approximately 1 h later and lasted for almost 10 h, suggesting that the interplanetary magnetic field was strongly southward for long time.

Influence of geomagnetic activity and atmospheric pressure on human arterial pressure during the solar cycle 24

Influence of geomagnetic activity and atmospheric pressure on human arterial pressure during the solar cycle 24

Influence of magnetic field on the spatial orientation in zebrafish (Danio rerio) (Cyprinidae) and Roach (Rutilus rutilus) (Cyprinidae)

Preferred direction of motion under influence of geomagnetic field and its modifications was registered in zebrafish (Danio rerio) raised in laboratory culture and in roach (Rutilus rutilus) from the Rybinsk Reservoir. In the geomagnetic field, specimens of zebrafish prefer two opposite directions oriented towards the north and south, while they prefer towards east and west at 90° turning of the horizontal component of geomagnetic field. The specimens of roach in the geomagnetic field prefer only the direction oriented towards east–northeast. This direction coincides with the direction along the canal where roach was sampled to the main river channel part of the Rybinsk Reservoir. At 90° rotation of the horizontal component of geomagnetic field, the direction turns to the south–southeast. The reasons for selection of certain directions in the geomagnetic field are discussed.

Influence of magnetic field on zebrafish activity and orientation in a plus maze

Influence of magnetic field on zebrafish activity and orientation in a plus maze