Solar wind drivers for low-latitude ionosphere models during geomagnetic storms

Abstract. On 29 December 2003, the Chinese spacecraft Tan Ce 1 (TC-1), the first component of the Double Star mission, was successfully launched within a low-latitude eccentric orbit. In the framework of the scientific cooperation between the Academy of Sciences of China and ESA, several European instruments, identical to those developed for the Cluster spacecraft, were installed on board this spacecraft. The HIA (Hot Ion Analyzer) instrument on board the TC-1 spacecraft is an ion spectrometer nearly identical to the HIA sensor of the CIS instrument on board the 4 Cluster spacecraft. This instrument has been specially adapted for TC-1. It measures the 3-D distribution functions of the ions between 5 eV/q and 32 keV/q without mass discrimination. TC-1 is like a fifth Cluster spacecraft to study the interaction of the solar wind with the magnetosphere and to study geomagnetic storms and magnetospheric substorms in the near equatorial plane. HIA was commissioned in February 2004. Due to the 2 RE higher apogee than expected, some in-flight improvements were needed in order to use HIA in the solar wind in the initial phase of the mission. Since this period HIA has obtained very good measurements in the solar wind, the magnetosheath, the dayside and nightside plasma sheet, the ring current and the radiation belts. We present here the first results in the different regions of the magnetosphere and in the solar wind. Some of them are very new and include, for example, ion dispersion structures in the bow shock and ion beams close to the magnetopause. The huge interest in the orbit of TC-1 is strongly demonstrated.

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Changes in the longitudinal structure of the low-latitude ionosphere during the July 2004 sequence of geomagnetic storms

Journal of Geophysical Research Atmospheres ◽

10.1029/2008ja013539 ◽

2008 ◽

Vol 113 (A11) ◽

pp. n/a-n/a ◽

Cited By ~ 9

Author(s):

N. M. Pedatella ◽

J. M. Forbes ◽

J. Lei ◽

J. P. Thayer ◽

K. M. Larson

Keyword(s):

Geomagnetic Storms ◽

Low Latitude ◽

Longitudinal Structure ◽

Low Latitude Ionosphere

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Effects of strong IMF <I>B<sub>z</sub></I> southward events on the equatorial and mid-latitude ionosphere

Annales Geophysicae ◽

10.5194/angeo-27-1175-2009 ◽

2009 ◽

Vol 27 (3) ◽

pp. 1175-1187 ◽

Cited By ~ 31

Author(s):

E. Astafyeva

Keyword(s):

Electric Fields ◽

Geomagnetic Storms ◽

The Other ◽

Negative Events ◽

Equatorial Anomaly ◽

Low Latitude ◽

Sudden Drop ◽

Ionospheric Response ◽

Peak Structure ◽

Low Latitude Ionosphere

Abstract. Dayside ionospheric response to five intense geomagnetic storms (Dst<−120 nT) that occurred in 2001–2005 was investigated by use of simultaneous TEC measurements by the CHAMP, SAC-C, TOPEX/Jason-1 satellites. Since the satellites passed over different longitudinal sectors and measured TEC in different range of altitudes, it was possible to obtain information about altitudinal and longitudinal ionosphere redistribution during these storms. Severe enhancements (up to ~350%) of the equatorial and mid-latitude TEC above ~430 km with concurrent traveling of the equatorial anomaly crests for a distance of 10–15° of latitude were observed during two of the five events analyzed here (6 November 2001 and 8 November 2004). This phenomenon, known as the dayside ionosphere uplift, or the "daytime super-fountain effect", occurred after sudden drop in IMF Bz and consequent penetration of the electric fields to the low-latitude ionosphere. However, the same order Bz negative events caused comparatively weak changes in the dayside TEC (up to ~80 TECU) during the other three events of 18 June 2003, 11 February 2004 and 24 August 2005. At the main phase of these storms there were mostly observed formation of the "typical" dual peak structure of the equatorial anomaly rather than the reinforcement of the fountain effect and the anomaly itself. Possible reasons and factors responsible for the development of the extreme ionosphere effects are discussed in the paper.

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A statistical analysis of the relationship between Pc4 and Pc5 ULF waves, solar winds and geomagnetic storms for predicting earthquake precursor signatures in low latitude regions

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/880/1/012010 ◽

2021 ◽

Vol 880 (1) ◽

pp. 012010

Author(s):

S N A Syed Zafar ◽

Roslan Umar ◽

N H Sabri ◽

M H Jusoh ◽

A Yoshikawa ◽

...

Keyword(s):

Solar Wind ◽

Geomagnetic Field ◽

Geomagnetic Storms ◽

Earthquake Precursor ◽

Ulf Waves ◽

Low Latitude ◽

Geomagnetic Indices ◽

Solar Winds ◽

Solar Wind Parameters ◽

The Relationship

Abstract Short-term earthquake forecasting is impossible due to the seismometer’s limited sensitivity in detecting the generation of micro-fractures prior to an earthquake. Therefore, there is a strong desire for a non-seismological approach, and one of the most established methods is geomagnetic disturbance observation. Previous research shows that disturbances in the ground geomagnetic field serves as a potential precursor for earthquake studies. It was discovered that electromagnetic waves (EM) in the Ultra-Low Frequency (ULF) range are a promising tool for studying the seismomagnetic effect of earthquake precursors. This study used a multiple regression approach to analyse the preliminary study on the relationship between Pc4 (6.7-22 mHz) and Pc5 (1.7-6.7 mHz) ULF magnetic pulsations, solar wind parameters and geomagnetic indices for predicting earthquake precursor signatures in low latitude regions. The ground geomagnetic field was collected from Davao station (7.00° N, 125.40° E), in the Philippines, which experiences nearby earthquake events (Magnitude <5.0, depth <100 km and epicentre distance from magnetometer station <100 km). The Pc5 ULF waves show the highest variance with four solar wind parameters, namely SWS, SWP, IMF-Bz, SIE and geomagnetic indices (SYM/H) prior to an earthquake event based on the regression model value of R2 = 0.1510. Furthermore, the IMF-Bz, SWS, SWP, SWE, and SYM/H were found to be significantly correlated with Pc5 ULF geomagnetic pulsation. This Pc5 ULF magnetic pulsation behaviour in solar winds and geomagnetic storms establishes the possibility of using Pc5 to predict earthquakes.

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Variation on Solar Wind Parameters and Total Electron Content Over Middle‐ to Low‐Latitude Regions During Intense Geomagnetic Storms

Radio Science ◽

10.1029/2020rs007129 ◽

2020 ◽

Vol 55 (11) ◽

Author(s):

Roshan Kumar Mishra ◽

Binod Adhikari ◽

Narayan Prasad Chapagain ◽

Rabin Baral ◽

Priyanka Kumari Das ◽

...

Keyword(s):

Solar Wind ◽

Total Electron Content ◽

Geomagnetic Storms ◽

Electron Content ◽

Low Latitude ◽

Total Electron ◽

Solar Wind Parameters

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Storm-time ionization enhancements at the topside low-latitude ionosphere

Annales Geophysicae ◽

10.5194/angeo-26-867-2008 ◽

2008 ◽

Vol 26 (4) ◽

pp. 867-876 ◽

Cited By ~ 15

Author(s):

A. Dmitriev ◽

H.-C. Yeh

Keyword(s):

Radiation Belt ◽

Temporal Dynamics ◽

Geomagnetic Storms ◽

Energetic Particles ◽

Low Latitude ◽

Ion Density ◽

Low Latitude Ionosphere ◽

Using Data ◽

Mev Protons ◽

Earth Radiation

Abstract. Ion density enhancements at the topside low-latitude ionosphere during a Bastille storm on 15–16 July 2000 and Halloween storms on 29–31 October 2003 were studied using data from ROCSAT-1/IPEI experiment. Prominent ion density enhancements demonstrate similar temporal dynamics both in the sunlit and in the nightside hemispheres. The ion density increases dramatically (up to two orders of magnitude) during the main phase of the geomagnetic storms and reaches peak values at the storm maximum. The density enhancements are mostly localized in the region of a South Atlantic Anomaly (SAA), which is characterized by very intense fluxes of energetic particles. The dynamics of near-Earth radiation was studied using SAMPEX/LEICA data on >0.6 MeV electrons and >0.8 MeV protons at around 600 km altitude. During the magnetic storms the energetic particle fluxes in the SAA region and in its vicinity increase more than three orders of magnitude. The location of increased fluxes overlaps well with the regions of ion density enhancements. Two mechanisms were considered to be responsible for the generation of storm-time ion density enhancements: prompt penetration of the interplanetary electric field and abundant ionization of the ionosphere by enhanced precipitation of energetic particles from the radiation belt.

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