A5003153404- Ionosphere and magnetosphere dynamics
- Earthquake Detection and Analysis
- GNSS positioning and interference
- Solar and Space Plasma Dynamics
- Geomagnetism and Paleomagnetism Studies
- Geophysics and Gravity Measurements
- Atmospheric Ozone and Climate
- Cervical Cancer and HPV Research
- Education and Teacher Training
- Advertising and Communication Studies
- Health and Medical Education
- Geotechnical and Geomechanical Engineering
- Silicone and Siloxane Chemistry
- Educational Innovations and Technology
- Employment, Labor, and Gender Studies
- Stress and Burnout Research
- Polymer composites and self-healing
- Solar Radiation and Photovoltaics
- Tropical and Extratropical Cyclones Research
- Social Issues and Policies in Latin America
- Plant and soil sciences
- Knowledge Societies in the 21st Century
- Developmental and Educational Neuropsychology
- Educational theories and practices
National Institute for Space Research
2015-2024
Universidade do Vale do Paraíba
2005-2019
This study presents the Global Self‐Consistent Model of Thermosphere, Ionosphere and Protonosphere (GSM TIP) numerical simulations 9–14 September 2005 geomagnetic storm effects in middle‐ low‐latitude ionosphere. Recent modifications to GSM TIP model include adding an empirical high‐energy electron precipitation introducing a high‐resolution (1 min) calculation region 2 field‐aligned currents cross‐cap potential difference. These resulted better representation such as penetration...
Abstract The equatorial electrojet (EEJ) is a narrow band of current flowing eastward at the ionospheric E region altitudes along dayside dip equator. Mutually perpendicular electric and magnetic fields over equator results in formation ionization anomaly (EIA), which turn generates large electron density variabilities. Simultaneous study on characteristics EEJ EIA necessary to understand role This helpful for improved estimation total content (TEC) range delays required satellite‐based...
This paper presents a study of thermospheric and ionospheric response to the 2008 minor sudden stratospheric warming (SSW) event. period was characterized by low solar geomagnetic activity. The performed using Global Self‐consistent Model Thermosphere, Ionosphere, Protonosphere (GSM TIP). results were compared with ionosonde data from Irkutsk, Kaliningrad, Sao Jose dos Campos, Jicamarca. SSW event modeled specifying temperature density perturbations at lower boundary GSM TIP (80 km...
The intense modifications in the ionosphere‐thermosphere system equatorial and low‐latitude regions associated with dynamic electrodynamic coupling from high to low latitudes chemical changes during geomagnetic storms are important space weather issues. In second half of October 2003, solar activity resulted one two major on 29 30 October. this paper we present discuss ionospheric sounding observations carried out Palmas São José dos Campos, Brazil (the Brazilian sector), Ho Chi Minh City,...
Abstract It is known that the equatorial and low‐latitude ionosphere characterized with typical dynamical phenomena namely, ionization anomaly (EIA). Accurate modeling of characteristic variations EIA more important to arrive at correct estimation range delays required for communication navigation applications. The total electron content (TEC) data from a chain Global Positioning System (GPS) receivers seven identified locations equator crest beyond along 315°E geographic longitude in...
Abstract The present study investigates the ionospheric total electron content (TEC) and F‐layer response in Southern Hemisphere equatorial, low, middle latitudes due to major sudden stratospheric warming (SSW) event, which took place during January–February 2009 Northern Hemisphere. In this study, using 17 ground‐based dual frequency GPS stations two ionosonde spanning from 2.8°N 53.8°S, longitudes 36.7°W 67.8°W over South American sector, it is observed that ionosphere was significantly...
The main purpose of this investigation is to study the ionospheric F region response induced by intense geomagnetic storm that occurred on 7–8 September 2002. index Dst reached a minimum −181 nT at 0100 UT 8 September. In study, we used observations from chain 12 GPS stations and another 6 digital ionosonde stations. It should be mentioned that, soon after sudden commencement (SC) 1637 7 September, TEC variations midlatitude in both hemispheres showed an positive phase. However, during...
Traveling ionospheric disturbances (TIDs) are wave-like in plasma density. They often observed during both quiet (medium-scale TID) and geomagnetically disturbed (large-scale conditions. Their amplitudes can reach double-digit percentages of the background density, their existence presents a challenge for accurate ionosphere specification. In this study, we examine TID properties using observations obtained two periods multiple ground space-borne instruments, such as magnetometers, Global...
We have examined the quiet time equatorial electrodynamics of ionosphere in postmidnight sector using satellite, GPS total electron content (TEC) and ionosonde data. ROCSAT‐1 vertical drift data are used to estimate electrodynamics, TOPEX altimeter TEC obtain density structure ionosphere. Ionosonde measure F layer height as function local time. analyzed 4 years (2001–2004) ( Kp ≤ 3) observations sector. found that very strong ionospheric anomalies (EIAs) (0100–0500 LT) during magnetically...
The Sun was very active in the early part of November 2004. During period 8–10 2004, intense geomagnetic disturbances with two superstorms were observed. In a companion paper (hereinafter referred to as 1), effects observed F region during 2004 Latin American sector presented. present paper, we investigate east Asian sector. We have used ionospheric sounding observations at Ho Chi Minh City (Vietnam) and Okinawa, Yamagawa, Kokubunji, Wakkanai (Japan) investigations. Also, GPS (several...
The Sun was very active in the early part of November 2004. During period 8–10 2004, intense geomagnetic disturbances with two superstorms were observed. In this paper, we have investigated generation and suppression equatorial ionospheric irregularities daytime changes F region electron density Latin American sector during disturbances. We present sounding observations carried out at Manaus Sao Jose dos Campos, Brazil, geomagnetically disturbed period. Also, GPS obtained from several...
Abstract. In the present investigation, we have studied response of ionospheric F-region in Latin American sector during intense geomagnetic storm 21–22 January 2005. This has been considered "anomalous" (minimum Dst reached −105 nT at 07:00 UT on 22 January) because main phase occurred northward excursion Bz component interplanetary magnetic fields (IMFs). The monthly mean F10.7 solar flux for month 2005 was 99.0 sfu. parameters observed by ionosondes Ramey (RAM; 18.5° N, 67.1° W), Puerto...
Abstract. The response of the ionospheric F-region in South American sector during super geomagnetic storms on 29 and 30 October 2003 is studied present investigation. In this paper, we sounding observations period 29–31 obtained at Palmas (a near equatorial location) Sao Jose dos Campos location under southern crest anomaly), Brazil, along with 27–31 from a chain GPS stations covering Imperatriz, to Rio Grande, Argentina. Also, complementary that include sequences all-sky images OI 777.4...
Abstract. We present the results of a comparative study spread-F signatures over five low-latitude sites: Chiangmai (CGM; 18.8° N, 98.9° E, mag. Lat. 8.8° N), Thailand; Tanjungsari (TNJ; 6.9° S, 107.6° 16.9° S), Indonesia; Palmas (PAL; 10.2° 311.8° 0.9° S) and São José Dos Campos (SJC; 23.2° 314.1° 14.0° Brazil; Tucumán (TUC; 26.9° 294.6° 16.8° Argentina. The investigation was based on simultaneous ionograms recorded by an FMCW (frequency-modulated continuous-wave) at CGM, IPS-71 (digital...