GUVI Biblio

High and mid latitude and near subsolar point ionospheric and thermospheric responses to the solar flares and geomagnetic storms during low solar activity periods of 2017 and 2020

The paper observes the super-imposed effects of intense and moderate solar flares and Coronal Mass Ejection (CME) and High Speed Solar Wind (HSSW) driven geomagnetic storm events on the ionosphere and thermosphere at mid and high latitudes during low solar activity periods. The observations are conducted over a fixed longitude (∼117°W geographic) during May 27–31, 2017 (duration with intense geomagnetic storm without any significant solar flare event), September 3–6, 2017 (duration with solar flare events), September ...

Sur, Dibyendu; Ray, Sarbani; Paul, Ashik;

Published by: Advances in Space Research      Published on: jul

YEAR: 2022     DOI: 10.1016/j.asr.2022.04.024

CME driven storms; HSSW driven storms; Joule heating; O/N ratio; Plasmaspheric contributions; Solar flare

Investigation of the negative ionospheric response of the 8 September 2017 geomagnetic storm over the European sector

In this study, we investigate the negative ionospheric response over the European sector during two storms that took place on 8 September 2017, primarily, by exploiting observations over ten European locations. The spatial and temporal variations of TEC, foF2 and hmF2 ionospheric characteristics are examined with the aim to explain the physical mechanisms underlying the strong negative ionospheric response. We detected very sharp electron density (in terms of foF2 and TEC) decrease during the main phases of the two storms an ...

Oikonomou, Christina; Haralambous, Haris; Paul, Ashik; Ray, Sarbany; Alfonsi, Lucilla; Cesaroni, Claudio; Sur, Dibyendu;

Published by: Advances in Space Research      Published on: aug

YEAR: 2022     DOI: 10.1016/j.asr.2022.05.035

Large-scale traveling ionospheric disturbances; Mid-latitude ionospheric trough; September 2017 geomagnetic storm; Swarm satellite

Statistics of GPS TEC at the northern EIA crest region of the Indian subcontinent during the solar cycle 24 (2013-2018): comparison with IRI-2016 and IRI-2012 models

In this study the statistics of ionospheric total electron content (TEC), derived from a GSV4004B dual-frequency Global Positioning System (GPS) receiver at Agartala station (23.450°N, 91.150°E) located in northern equatorial ionization anomaly (EIA) crest region of the Indian subcontinent, is reported with a performance analysis of IRI-2016 and IRI-2012 models during the ascending, maxima, declining and minima phases (2013-2018) of the solar cycle 24. Variations of model total electron content, as obtained from the IRI-20 ...

Patari, Arup; Paul, Bapan; Guha, Anirban;

Published by: Astrophysics and Space Science      Published on: may

YEAR: 2021     DOI: 10.1007/s10509-021-03950-6

EIA; EUV flux; F10.7; GPS TEC; IRI-2012 TEC; IRI-2016 TEC; SSN

Impact of CME and HSSW driven geomagnetic storms on thermosphere and ionosphere as observed from mid-latitudes

The present paper reports magnetospheric-thermospheric-ionospheric interactions, observed during geomagnetically disturbed periods in 2015–2016 from mid-latitude stations located in the US-Pacific longitudes (\textasciitilde120°W geographic). These interactions have been analyzed for a series of Coronal Mass Ejection (CME) and High Speed Solar Wind (HSSW) driven geomagnetic storms during the moderate solar activity periods. The geomagnetically disturbed periods under consideration in this paper have an interesting feature ...

Sur, Dibyendu; Ray, Sarbani; Paul, Ashik;

Published by: Advances in Space Research      Published on: aug

YEAR: 2021     DOI: 10.1016/j.asr.2021.03.027

CME and HSSW storms; Joule heating; Meridional and zonal wind; O/N ratio; Plasma transport; VTEC

Multi-wavelength coordinated observations of ionospheric irregularity structures from an anomaly crest location during unusual solar minimum of the 24th cycle

The present paper reports coordinated ionospheric irregularity measurements at optical as well as GPS wavelengths. Optical measurements were obtained from Tiny Ionospheric Photometer (TIP) sensors installed onboard the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) satellites. GPS radio signals were obtained from a dual frequency GPS receiver operational at Calcutta (22.58\textdegreeN, 88.38\textdegreeE geographic; geomagnetic dip: 32.96\textdegree; 13.00\textdegreeN, 161.63\textdegreeE g ...

Paul, Ashik; Sur, Dibyendu; Haralambous, Haris;

Published by: Advances in Space Research      Published on: 03/2020

YEAR: 2020     DOI: 10.1016/j.asr.2019.11.035

GPS radio measurements; ionospheric irregularities; Northern crest of EIA; Optical measurements; solar minimum; TIP

Effects of CME and CIR induced geomagnetic storms on low-latitude ionization over Indian longitudes in terms of neutral dynamics

Chakraborty, Sumanjit; Ray, Sarbani; Sur, Dibyendu; Datta, Abhirup; Paul, Ashik;

Published by: Advances in Space Research      Published on:

YEAR: 2020     DOI:

I. Ionospheric Response to the Second Strongest Geomagnetic Storm of the Solar Cycle 24: First Results from the Arabian Peninsula

Dayanandan, Baiju; Paul, Bapan; Galav, Praveen;

Published by:       Published on:

YEAR: 2020     DOI:

Study of the low and mid-latitude ionospheric response to the geomagnetic storm of 20th December 2015

Paul, Bapan; Gordiyenko, Galina; Galav, Praveen;

Published by: Astrophysics and Space Science      Published on:

YEAR: 2020     DOI:

Response of Equatorial Ionization in Indian Longitudes to HSSW Driven Geomagnetic Storm

Sur, Dibyendu; Firdaus, Jasmine; Paul, Trisha; Dutta, Raktima; Bhattacharyya, Chaitali;

Published by:       Published on:

YEAR: 2020     DOI:

Conjugate hemispheric response of earth\textquoterights ionosphere due to geomagnetic storms occurred during two equinox periods

The ionospheric response of two geomagnetic storms of 2016 occurred during spring equinox (5-8 March, 2016) and autumn equinox (12-15 October, 2016) is investigated using the total electron content (TEC) data derived from Global Positioning System (GPS) receivers located in the equatorial ionization anomaly (EIA) crest regions at northern hemisphere (Tripura University, Agartala, India) and southern hemisphere (Karratha, Australia). While in southern EIA station ionospheric responses for the two storms are found to be sym ...

Patari, Arup; De, Barin; Guha, Anirban; Paul, Bapan;

Published by: Journal of Physics: Conference Series      Published on: 10/2019

YEAR: 2019     DOI: 10.1088/1742-6596/1330/1/012004

Effects of CME and CIR induced geomagnetic storms on low-latitude ionization over Indian longitudes in terms of neutral dynamics

This paper presents the response of the ionosphere during the intense geomagnetic storms of October 12\textendash20, 2016 and May 26\textendash31, 2017 which occurred during the declining phase of the solar cycle 24. Total Electron Content (TEC) from GPS measured at Indore, Calcutta and Siliguri having geomagnetic dips varying from 32.23\textdegreeN, 32\textdegreeN and 39.49\textdegreeN respectively and at the International GNSS Service (IGS) stations at Lucknow (beyond anomaly crest), Hyderabad (between geomagnetic equat ...

Chakraborty, S.; Ray, S.; Sur, D.; Datta, A.; Paul, A.;

Published by: Advances in Space Research      Published on: 10/2019

YEAR: 2019     DOI: 10.1016/j.asr.2019.09.047

Response of the Earth\textquoterights equatorial ionosphere during the severe G4-class geomagnetic storm of 8 ^th September 2017

Equatorial and low latitude ionospheric response of the 8^th September 2017 severe G4-class geomagnetic storm is investigated using the total electron content (TEC) data from a longitudinal chain of global positioning system (GPS) receivers over Asian, African and American sectors. During the main phase, a positive storm effect is observed over Asian sector, a complete negative storm effect over African sector and both are observed over American sector. A sharp increase in peak TEC is observed over the complete ...

Paul, Bapan; Patari, Arup; De, Barin; Guha, Anirban;

Published by: Journal of Physics: Conference Series      Published on: 10/2019

YEAR: 2019     DOI: 10.1088/1742-6596/1330/1/012005

Response of the Earth’s equatorial ionosphere during the severe G4-class geomagnetic storm of 8th September 2017

Paul, Bapan; Patari, Arup; De, Barin; Guha, Anirban;

Published by:       Published on:

YEAR: 2019     DOI:

Conjugate hemispheric response of earth’s ionosphere due to geomagnetic storms occurred during two equinox periods

Patari, Arup; De, Barin; Guha, Anirban; Paul, Bapan;

Published by:       Published on:

YEAR: 2019     DOI:

Observations of storm-time thermospheric O/N2 ratio and TEC in the northern hemisphere during intense geomagnetic storms of 2015-2017

It has already been established that during the main phase and recovery phase of any geomagnetic storm, thermospheric O/N2 column density ratio decreases in the high latitudes

Sur, Dibyendu; Ray, Sarbani; Paul, Ashik;

Published by:       Published on:

YEAR: 2019     DOI:

Latitudinal variation of F-region ionospheric response during three strongest geomagnetic storms of 2015

The latitudinal ionospheric response of the three strongest geomagnetic storms of 2015 of the current solar cycle 24 during 16\textendash19 March 2015, 21\textendash24 June 2015 and 19\textendash22 December 2015 is investigated using the total electron content data derived from a latitudinal chain of Global Positioning System (GPS) receivers extending from 70\textdegreeN to 70\textdegreeS. The storm time perturbations of the ionosphere during main and recovery phase is presented by the GPS derived vertical total electron ...

Paul, Bapan; De, Barin; Guha, Anirban;

Published by: Acta Geodaetica et Geophysica      Published on: 12/2018

YEAR: 2018     DOI: 10.1007/s40328-018-0221-4

Latitudinal features of Total Electron Content over the African and European longitude sector following the St. Patrick’s day storm of 2015

Paul, A; Kascheyev, A; Rodriguez-Bouza, M; PATHAK, K; Ferreira, AA; Shetti, D; Yao, JN;

Published by: Advances in Space Research      Published on:

YEAR: 2018     DOI:

Total electron content responses to HILDCAAs and geomagnetic storms over South America

Total electron content (TEC) is extensively used to monitor the ionospheric behavior under geomagnetically quiet and disturbed conditions. This subject is of greatest importance for space weather applications. Under disturbed conditions the two main sources of electric fields, which are responsible for changes in the plasma drifts and for current perturbations, are the short-lived prompt penetration electric fields (PPEFs) and the longer-lasting ionospheric disturbance dynamo (DD) electric fields. Both mechanisms modulate ...

Negreti, Patricia; de Paula, Eurico; Candido, Claudia;

Published by: Annales Geophysicae      Published on: 06/2017

YEAR: 2017     DOI: 10.5194/angeo-35-1309-2017

Analysis of High-Latitude Ionospheric Processes During the Nov 2015 HSS and CME-Induced Geomagnetic Storm: A Multi-Instrument Observational Approach

Durgonics, Tibor; Komjathy, Attila; Verkhoglyadova, Olga; Hoeg, Per; Paul, Ashik;

Published by:       Published on:

YEAR: 2016     DOI:

Characteristics of post-midnight L-band scintillation in the transition region from the equatorial to mid-latitudes over the Indian longitude sector using COSMIC, C/NOFS and GPS measurements

Occurrence of L band scintillations around midnight and postmidnight hours have not been well studied and reported from the higher equatorial latitudes in the transition region from the equatorial to midlatitudes over the Indian longitude sector. The present paper reports cases of postmidnight L band scintillation observations by COSMIC during March 2014 over the Indian longitude sector. GPS\ S₄measurements from the International Global Navigation Satellite Systems Service station at Lucknow (26.9 ...

Paul, A.; Haralambous, H.; Oikonomou, C.;

Published by: Radio Science      Published on: 12/2015

YEAR: 2015     DOI: 10.1002/2015RS005807

postmidnight L band scintillation over Indian longitude sector

Characteristics of postmidnight L band scintillation in the transition region from the equatorial to midlatitudes over the Indian longitude sector using COSMIC, C/NOFS, and GPS measurements

Paul, A; Haralambous, H; Oikonomou, C;

Published by: Radio Science      Published on:

YEAR: 2015     DOI:

Effects of transionospheric signal decorrelation on Global Navigation Satellite Systems (GNSS) performance studied from irregularity dynamics around the northern crest of the EIA

Transionospheric satellite navigation links operate primarily at L band and are frequently subject to severe degradation of performances arising out of ionospheric irregularities. Various characteristic features of equatorial ionospheric irregularity bubbles like the drift velocity, characteristic velocity, decorrelation time, and decorrelation distance can be determined using spaced aerial measurements at VHF. These parameters measured at VHF from a station Calcutta situated near the northern crest of the Equatorial Ioni ...

Das, T.; Roy, B.; Paul, A.;

Published by: Radio Science      Published on: 10/2014

YEAR: 2014     DOI: 10.1002/rds.v49.1010.1002/2014RS005406

GNSS position determination accuracy under adverse ionospheric conditions; GUVI; irregularity dynamics at VHF

GPS L1-Frequency Observations of Equatorial Scintillations and Irregularity Zonal Velocities

In this work, the climatology of ionospheric scintillations at global positioning system (GPS) L-band frequency and the zonal drift velocities of scintillation-producing irregularities were depicted for the equatorial observatory of S\~ao Luis (2.33\textdegreeS; 44.21\textdegreeW; dip latitude 1.3\textdegreeS), Brazil. This is the first time that the hourly, monthly, and seasonal variations of scintillations and irregularity zonal drifts at S\~ao Luis were characterized during periods of different solar activity levels (f ...

Muella, Marcio; de Paula, Eurico; Jonah, Olusegun;

Published by: Surveys in Geophysics      Published on: 08/2014

YEAR: 2014     DOI: 10.1007/s10712-013-9252-0

GPS; Ionospheric drifts; ionospheric irregularities; Ionospheric scintillation

Scintillation-producing Fresnel-scale irregularities associated with the regions of steepest TEC gradients adjacent to the equatorial ionization anomaly

Muella, M.; Kherani, E.; de Paula, E.; Cerruti, A.; Kintner, P.; Kantor, I.; Mitchell, C.; Batista, I.; Abdu, M.;

Published by: Journal of Geophysical Research      Published on: Jan-01-2010

YEAR: 2010     DOI: 10.1029/2009JA014788

Gravity wave initiation of equatorial spread F/plasma bubble irregularities based on observational data from the SpreadFEx campaign

The data from ground based experiments conducted during the 2005 SpreadFEx campaign in Brazil are used, with the help of theoretical model calculations, to investigate the precursor conditions, and especially, the role of gravity waves, in the instability initiation leading to equatorial spread F development. Data from a digisonde and a 30 MHz coherent back-scatter radar operated at an equatorial site, Sao Luis (dip angle: 2.7\textdegree) and from a digisonde operated at another equatorial site (dip angle: -11.5\textdegre ...

Abdu, M.; Kherani, Alam; Batista, I.; de Paula, E.; Fritts, D.; Sobral, J.;

Published by: Annales Geophysicae      Published on: Jan-01-2009

YEAR: 2009     DOI: 10.5194/angeo-27-2607-2009

Overview and summary of the Spread F Experiment (SpreadFEx)

We provide here an overview of, and a summary of results arising from, an extensive experimental campaign (the Spread F Experiment, or SpreadFEx) performed from September to November 2005, with primary measurements in Brazil. The motivation was to define the potential role of neutral atmosphere dynamics, specifically gravity wave motions propagating upward from the lower atmosphere, in seeding Rayleigh-Taylor instability (RTI) and plasma bubbles extending to higher altitudes. Campaign measurements focused on the Brazilian ...

Fritts, D.; Abdu, M.; Batista, B.; Batista, I.; Batista, P.; Buriti, R.; Clemesha, B.; Dautermann, T.; de Paula, E.; Fechine, B.; Fejer, B.; Gobbi, D.; Haase, J.; Kamalabadi, F.; Kherani, E.; Laughman, B.; Lima, P.; Liu, H.-L.; Medeiros, A.; Pautet, P.-D.; Riggin, D.; Rodrigues, F.; Sabbas, F.; Sobral, J.; Stamus, P.; Takahashi, H.; Taylor, M.; Vadas, S.; Vargas, F.; Wrasse, C.;

Published by: Annales Geophysicae      Published on: Jan-01-2009

YEAR: 2009     DOI: 10.5194/angeo-27-2141-2009

Simultaneous observation of ionospheric plasma bubbles and mesospheric gravity waves during the SpreadFEx Campaign

Takahashi, H.; Taylor, M.; Pautet, P.-D.; Medeiros, A.; Gobbi, D.; Wrasse, C.; Fechine, J.; Abdu, M.; Batista, I.; Paula, E.; Sobral, J.; Arruda, D.; Vadas, S.; Sabbas, F.; Fritts, D.;

Published by: Annales Geophysicae      Published on: Jan-01-2009

YEAR: 2009     DOI: 10.5194/angeo-27-1477-2009

The Spread F Experiment (SpreadFEx): Program overview and first results

Fritts, D.; Abdu, M.; Batista, B.; Batista, I.; Batista, P.; Buriti, R.; Clemesha, B.; Dautermann, T.; de Paula, E.; Fechine, B.; Fejer, B.; Gobbi, D.; Haase, J.; Kamalabadi, F.; Kherani, E.; Laughman, B.; Lima, J.; Liu, H.-L.; Medeiros, A.; Pautet, P.-D.; Riggin, D.; Rodrigues, F.; Sabbas, Sao; Sobral, J.; Stamus, P.; Takahasi, H.; Taylor, M.; Vadas, S.; Vargas, F.; Wrasse, C.;

Published by: Earth Planets Space      Published on:

YEAR: 2009     DOI:

Disturbed time observations of the temporal dependence and dynamics of TEC, scintillation, and ionospheric irregularity zonal drifts

Muella, Marcio; de Paula, Eurico; Kintner, Paul; Kantor, Ivan; Cerruti, Alessandro; Mitchell, Cathryn; Crowley, Geoff; Smorigo, Paulo; Batista, Inez;

Published by: 37th COSPAR Scientific Assembly      Published on:

YEAR: 2008     DOI:

Coherent backscatter radar imaging in Brazil: large-scale waves in the bottomside F-region at the onset of equatorial spread F

Rodrigues, FS; Hysell, DL; de Paula, ER;

Published by:       Published on:

YEAR: 2008     DOI:

Simultaneous observation of ionospheric plasma bubble and mesospheric gravity wave activities during CAWSES 2005 SpreadFEx Campaign

During the SpreadFEx campaign from September 22 to November 8, 2005, two airglow CCD imagers, located at near Brasilia (14.8S, 47.6W, Mag. 10S) and at Cariri (7.4S, 36.5W, Mag. 9S) were operated simultaneously and measured the equatorial ionospheric bubble structures and their time evolution by monitoring the OI 6300 emission. From the 10 nights of coincident data, we observed that on some nights the bubbles was formed at the west of Cariri, but not seen from the Brasilia site. This suggests that the bubble formation and dev ...

Takahashi*, H.; Pautet, P.-D.; Fechine, J.; Abdu, M.; Batista, I.; Paula, E.; Sobral, J.H.A.; Gobbi, D.; Arruda, D.; Batista, P.; Sabba, F.; Taylor, M.; Medeiros, A.; Buriti, R.; Wrasse, C.; Fritts, D.;

Published by:       Published on:

YEAR: 2007     DOI: 10.1190/sbgf2007-404