Response of GOLD Retrieved Thermospheric Temperatures to Geomagnetic Activities of Varying Magnitudes

Extreme geomagnetic activities: a statistical study

Earth Planets and Space ◽

10.1186/s40623-020-01261-8 ◽

2020 ◽

Vol 72 (1) ◽

Author(s):

Ryuho Kataoka

Keyword(s):

Magnetic Storms ◽

Magnetic Observatory ◽

Statistical Distributions ◽

Limited Data ◽

Data Set ◽

Sudden Commencements ◽

The One ◽

Log Normal ◽

Geomagnetic Activities ◽

Log Normal Distribution

Abstract Statistical distributions are investigated for magnetic storms, sudden commencements (SCs), and substorms to identify the possible amplitude of the one in 100-year and 1000-year events from a limited data set of less than 100 years. The lists of magnetic storms and SCs are provided from Kakioka Magnetic Observatory, while the lists of substorms are obtained from SuperMAG. It is found that majorities of events essentially follow the log-normal distribution, as expected from the random output from a complex system. However, it is uncertain that large-amplitude events follow the same log-normal distributions, and rather follow the power-law distributions. Based on the statistical distributions, the probable amplitudes of the 100-year (1000-year) events can be estimated for magnetic storms, SCs, and substorms as approximately 750 nT (1100 nT), 230 nT (450 nT), and 5000 nT (6200 nT), respectively. The possible origin to cause the statistical distributions is also discussed, consulting the other space weather phenomena such as solar flares, coronal mass ejections, and solar energetic particles.

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Case study on total electron content enhancements at low latitudes during low geomagnetic activities before the storms

Annales Geophysicae ◽

10.5194/angeo-26-893-2008 ◽

2008 ◽

Vol 26 (4) ◽

pp. 893-903 ◽

Cited By ~ 27

Author(s):

◽

Keyword(s):

Total Electron Content ◽

Geomagnetic Activity ◽

Electron Content ◽

Low Latitude ◽

Total Electron ◽

Defense Meteorological Satellite Program ◽

Low Latitudes ◽

Global Ionospheric Maps ◽

Geomagnetic Activities

Abstract. Sometimes the ionospheric total electron content (TEC) is significantly enhanced during low geomagnetic activities before storms. In this article, we investigate the characteristics of those interesting TEC enhancements using regional and global TEC data. We analyzed the low-latitude TEC enhancement events that occurred around longitude 120° E on 10 February 2004, 21 January 2004, and 4 March 2001, respectively. The TEC data are derived from regional Global Positioning System (GPS) observations in the Asia/Australia sector as well as global ionospheric maps (GIMs) produced by Jet Propulsion Laboratory (JPL). Strong enhancements under low geomagnetic activity before the storms are simultaneously presented at low latitudes in the Asia/Australia sector in regional TEC and JPL GIMs. These TEC enhancements are shown to be regional events with longitudinal and latitudinal extent. The regions of TEC enhancements during these events are confined at narrow longitude ranges around longitude 120° E. The latitudinal belts of maxima of enhancements locate around the northern and southern equatorial ionization anomaly (EIA) crests, which are consistent with those low-latitude events presented by Liu et al. (2008). During the 4 March 2001 event, the total plasma density Ni observed by the Defense Meteorological Satellite Program (DMSP) spacecraft F13 at 840 km altitude are of considerably higher values on 4 March than on the previous day in the TEC enhanced regions. Some TEC enhancement events are possibly due to contributions from auroral/magnetospheric origins; while there are also quasi-periodic enhancement events not related to geomagnetic activity and associated probably with planetary wave type oscillations (e.g. the 6 January 1998 event). Further investigation is warrented to identify/separate contributions from possible sources.

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Geomagnetic activities of the U. S. Coast and Geodetic Survey

Journal of Geophysical Research Atmospheres ◽

10.1029/jz061i003p00579-07 ◽

1956 ◽

Vol 61 (3) ◽

pp. 579-579

Author(s):

Keyword(s):

Geodetic Survey ◽

Geomagnetic Activities

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Geomagnetic activities of the United States Coast and Geodetic Survey

Journal of Geophysical Research Atmospheres ◽

10.1029/jz057i003p00433-03 ◽

1952 ◽

Vol 57 (3) ◽

pp. 433-434

Author(s):

Keyword(s):

United States ◽

The United States ◽

Geodetic Survey ◽

Geomagnetic Activities

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Monitoring potential ionospheric changes caused by Van earthquake (Mw 7.2)

10.5194/angeo-2018-105 ◽

2018 ◽

Author(s):

Samed Inyurt ◽

Selcuk Peker ◽

Cetin Mekik

Keyword(s):

Solar Activity ◽

Local Time ◽

Earthquake Prediction ◽

Statistical Test ◽

Van Earthquake ◽

The North ◽

The Times ◽

Geomagnetic Activities

Abstract. Many scientists from different disciplines have studied earthquakes for many years. As a result of these studies, it has been proposed that some changes take place in the ionosphere layer before, during or after earthquakes, and the ionosphere should be monitored in earthquake prediction studies. This study investigates the changes in the ionosphere created by the earthquake with magnitude of Mw=7.2 in the northwest of the Lake Erçek which is located to the north of the province of Van in Turkey on 23 October 2011 and at 1.41 pm local time (−3 UT) with the epicenter of 38.75° N, 43.36° E using the TEC values obtained by the Global Ionosphere Models (GIM) created by IONOLAB-TEC and CODE. In order to see whether the ionospheric changes obtained by the study in question were caused by the earthquake or not, the ionospheric conditions were studied by utilizing indices providing information on solar and geomagnetic activities (F10.7 cm, Kp, Dst). One of the results of the statistical test on the TEC values obtained from the both models, positive and negative anomalies were obtained for the times before, on the day of and after the earthquake, and the reasons for these anomalies are discussed in detail in the last section of the study. As the ionospheric conditions in the analyzed days were highly variable, it was thought that the anomalies were caused by geomagnetic effects, solar activity and the earthquake.

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