GUVI Biblio

Ionospheric Response to the 23-31 August 2018 Geomagnetic Storm in the Europe-African Longitude Sector Using Multi-Instrument Observations

This study presents ionospheric responses of the mid and low-latitude region in the Europe-African longitude sector (along 30 +/- 10 deg E) to the intense geomagnetic storm of 23–31 August 2018 (SYM-Hmin = −207 nT) using the Global Ionospheric Map (GIM) and Global Positioning System (GPS) receivers data, the satellite data (SWARM, Defense Meteorological Satellite Program (DMSP), Global Ultraviolet Imager on board the Thermosphere, Ionosphere, Mesosphere Energetics and Dynamics (GUVI/TIMED)), and Prompt Penetration Equato ...

Dugassa, Teshome; Mezgebe, Nigussie; Habarulema, John; Habyarimana, Valence; Oljira, Asebe;

Published by: Advances in Space Research      Published on:

YEAR: 2022     DOI: 10.1016/j.asr.2022.10.063

The ionospheric response to high-intensity long duration continuous AE activity (HILDCAA) event (13--15 April 2005) over mid-latitude African region

The ionospheric responses to High-Intensity Long Duration Continuous Auroral Electrojet Activity (HILDCAA) event which happened following the CIR-driven storm were studied over the southern hemisphere mid-latitude in the African sector. The 13–15 April 2005 event was analysed to understand some of the mechanisms responsible for the ionospheric changes during HILDCAA event. The ionosonde critical frequency of F2 layer (foF2) and Global Navigation Satellite System (GNSS) Total Electron Content (TEC) were used to analyse the ...

Matamba, Tshimangadzo; Habarulema, John;

Published by: Advances in Space Research      Published on: jan

YEAR: 2021     DOI: 10.1016/j.asr.2020.10.034

CIR; HILDCAA; Ionospheric storm; PPEF; TEC; TIDs

Equatorial and low-latitude ionospheric TEC response to CIR-driven geomagnetic storms at different longitude sectors

In this study the response of ionospheric F-region to 18–21 September 2014, 19–24 January 2016, and 07–10 March 2016 CIR-driven storms in the equatorial and low-latitude region of

Dugassa, Teshome; Habarulema, John; Nigussie, Melessew;

Published by: Advances in Space Research      Published on:

YEAR: 2020     DOI: 10.1016/j.asr.2020.07.003

Ionospheric response at conjugate locations during the 7—8 September 2017 geomagnetic storm over the Europe-African longitude sector

This paper focuses on unique aspects of the ionospheric response at conjugate locations over Europe and South Africa during the 7–8 September 2017 geomagnetic storm including

Habarulema, John; Katamzi-Joseph, Zama; a, Dalia; Nndanganeni, Rendani; Matamba, Tshimangadzo; Tshisaphungo, Mpho; Buchert, Stephan; Kosch, Michael; Lotz, Stefan; Cilliers, Pierre; , others;

Published by: Journal of Geophysical Research: Space Physics      Published on:

YEAR: 2020     DOI: 10.1029/2020JA028307

Midlatitude ionospheric changes to four great geomagnetic storms of solar cycle 23 in Southern and Northern Hemispheres

This paper presents an investigation of ionospheric response to great (Dst<=\textendash350 nT) geomagnetic storms that occurred during solar cycle 23. The storm periods analyzed are 29 March to 2 April 2001, 27\textendash31 October 2003, 18\textendash23 November 2003, and 6\textendash11 November 2004. Global Navigation Satellite System, total electron content (TEC), and ionosonde critical frequency of F 2 layer (f o F 2 ) data over Southern Hemisphere (African sector) and Northern Hemisphere (European sector) midlatitudes ...

Matamba, Tshimangadzo; Habarulema, John; a, Dalia;

Published by: Space Weather      Published on: 12/2016

YEAR: 2016     DOI: 10.1002/swe.v14.1210.1002/2016SW001516

Assessing ionospheric response during some strong storms in solar cycle 24 using various data sources

We present an analysis of a regional ionospheric response during six strong storms (-200\ nT\ <=Dst<=-100\ nT) that occurred in 2012 for the geographic latitudinal coverage of 10\textdegreeS\textendash40\textdegreeS within a longitude sector of 10\textdegreeE\textendash40\textdegreeE. Although these storms occurred during the same solar activity period and were all coronal mass ejection driven, their impacts and associated features on the ionosphere have been found different due t ...

Habarulema, John; Katamzi, Zama; Sibanda, Patrick; Matamba, Tshimangadzo;

Published by: Journal of Geophysical Research: Space Physics      Published on: 12/2016

YEAR: 2016     DOI: 10.1002/jgra.v122.110.1002/2016JA023066

Statistical analysis of the ionospheric response during geomagnetic storm conditions over South Africa using ionosonde and GPS data

This paper presents a statistical analysis of ionospheric response over ionosonde stations Grahamstown (33.3\textdegreeS, 26.5\textdegreeE, geographic) and Madimbo (22.4\textdegreeS, 30.9\textdegreeE, geographic), South Africa, during geomagnetic storm conditions which occurred during the period 1996\textendash2011. Such a climatological study is important in establishing local ionospheric behavior trend which later forms a basis for accurate modeling and forecasting electron density and critical frequency of the\ 

Matamba, Tshimangadzo; Habarulema, John; McKinnell, Lee-Anne;

Published by: Space Weather      Published on: 09/2015

YEAR: 2015     DOI: 10.1002/swe.v13.910.1002/2015SW001218

Geomagnetic storms; ionospheric storm effects; midlatitude ionosphere

Traveling ionospheric disturbances observed at South African midlatitudes during the 29--31 October 2003 geomagnetically disturbed period

This paper presents traveling ionospheric disturbances (TIDs) observations from GPS measurements over the South African region during the geomagnetically disturbed period of 29\textendash31 October 2003. Two receiver arrays, which were along two distinct longitudinal sectors of about 18\textdegree-20\textdegree and 27\textdegree-28\textdegree were used in order to investigate the amplitude, periods and virtual propagation characteristics of the storm induced ionospheric disturbances. The study revealed a large sudden TEC ...

Katamzi, Zama; Habarulema, John;

Published by: Advances in Space Research      Published on: 01/2014

YEAR: 2014     DOI: 10.1016/j.asr.2013.10.019

geomagnetic storm; Substorm; Total electron content (TEC); Traveling ionospheric disturbances (TIDs)

Statistical analysis of the ionospheric response during geomagnetic storm conditions over South Africa using ionosonde and GPS data

Matamba, Tshimangadzo; Habarulema, John; McKinnell, Lee-Anne;

Published by: Space Weather      Published on:

YEAR: 2014     DOI: https://doi.org/10.1002/2015SW001218

ionospheric storm effects; Geomagnetic storms; midlatitude ionosphere

Estimating the propagation characteristics of large-scale traveling ionospheric disturbances using ground-based and satellite data

In this article, the propagation characteristics of large-scale traveling ionospheric disturbances (LS TIDs) are estimated during the geomagnetic storm periods of 14\textendash16 May 2005 and 25\textendash27 September 2011 over South Africa. One and two GPS arrays have been independently considered for the storms of 15 May 2005 and 26 September 2011, respectively. The average periods of dominant modes (≈ 2.5\textendash3.5h) in the time series data were determined by applying wavelet analysis on both ionosonde and GPS da ...

Habarulema, John; Katamzi, Zama; McKinnell, Lee-Anne;

Published by: Journal of Geophysical Research: Space Physics      Published on: 12/2013

YEAR: 2013     DOI: 10.1002/2013JA018997

characteristics of large scale TIDs; Geomagnetic storms; ionospheric irregularities

A comparative study of TEC response for the African equatorial and mid-latitudes during storm conditions

The solar wind effects on the Earth\textquoterights environment are studied for their basic scientific values and crucial practical impacts on technological systems. This paper reports results of Total Electron Content (TEC) changes during two successive ionospheric storms of 7\textendash12 November 2004 using GPS data derived from dual frequency receivers located at African equatorial and midlatitudes. In the geographic coordinate system, equatorial TEC variability is considered over Libreville (0.36\textdegreeN, 9.67\te ...

Habarulema, John; McKinnell, Lee-Anne; a, Dalia; Zhang, Yongliang; Seemala, Gopi; Ngwira, Chigomezyo; Chum, Jaroslav; Opperman, Ben;

Published by: Journal of Atmospheric and Solar-Terrestrial Physics      Published on: 09/2013

YEAR: 2013     DOI: 10.1016/j.jastp.2013.05.008

African equatorial and midlatitude TEC dynamics; Magnetic storms; TIDs