A5086570143- Ionosphere and magnetosphere dynamics
- Earthquake Detection and Analysis
- Lightning and Electromagnetic Phenomena
- Solar and Space Plasma Dynamics
- GNSS positioning and interference
- Geomagnetism and Paleomagnetism Studies
- Seismic Waves and Analysis
- earthquake and tectonic studies
- Geophysics and Gravity Measurements
- Tropical and Extratropical Cyclones Research
- Geophysics and Sensor Technology
- Radio Wave Propagation Studies
- Impact of Light on Environment and Health
- Seismology and Earthquake Studies
- Atmospheric Ozone and Climate
- Meteorological Phenomena and Simulations
- Atmospheric aerosols and clouds
- Fire effects on ecosystems
- Nuclear reactor physics and engineering
- Nuclear Engineering Thermal-Hydraulics
- Psychopathy, Forensic Psychiatry, Sexual Offending
- Agricultural Practices and Plant Genetics
- Optical Wireless Communication Technologies
- Working Capital and Financial Performance
- Semiconductor Lasers and Optical Devices
Babasaheb Bhimrao Ambedkar University
2022-2025
Weatherford College
2020-2022
Doon University
2018-2021
Banaras Hindu University
2012-2017
Georgia Institute of Technology
2016
Geological Survey of India
2010-2015
University of Allahabad
2014
Dispersive atmospherics (tweeks) observed during 2010 simultaneously at two low‐latitude stations, Allahabad (geomagnetic latitude, 16.05°N) and Nainital 20.48°N), have been used to estimate the nighttime D region electron density ionospheric reflection height under local propagation (21:00–02:00 LT or 15:30–20:30 UT). The analysis of recorded tweeks both stations on five international quiet days one month each from summer (June), winter (January), equinox (March) seasons shows that varies...
Abstract The response of the D region low‐latitude ionosphere has been examined for extreme space weather event 14–16 December 2006 associated with a X1.5 solar flare and an intense geomagnetic storm ( Dst = −146 nT) using VLF signals from Northwest Cape, Australia (NWC) (19.8 kHz) Lualualei, Hawaii (callsign NPM) (21.4 transmitters monitored at Suva (Geographic Coordinates, 18.10°S, 178.40°E), Fiji. Modeling amplitude phase enhancements NWC (3.6 dB, 223°) NPM (5 153°) Long‐Wave Propagation...
Abstract We present a critical analysis of the observations and interpretation VLF subionospheric measurements related to main Nepal Gorkha earthquake which occurred on 25 April 2015 ( M w 7.8) its major aftershock 12 May 7.3). The narrowband signal used is from North West Cape (NWC) (19.8 kHz) transmitter located in Australia recorded at Allahabad (latitude 25.41°N, longitude 81.93°E). very close (~360 km) these epicenters. Two widely analysis, viz., (1) terminator time (2) nighttime...
Solar eclipses present a valuable opportunity for controlled in situ ionosphere studies. This work explores the response of upper atmosphere’s F-layer during total eclipse 8 April 2024, which was primarily visible across North and South America. Employing multi-instrument approach, we analyze impact on ionosphere’s Total Electron Content (TEC) Very Low Frequency (VLF) signals over three-day period encompassing (7–9 2024). Ground-based observations leverage data from ten International GNSS...
<title>Abstract</title> The present study investigates the effect of solar terminator time (TT) on low- and equatorial-latitude transmitter-receiver great circle path (TRGCP). Very Low Frequency (VLF) signals from VTX (18.6 kHz) NWC (19.8 transmitters, recorded at low-latitude Indian station, Dehradun, are utilized. TRGCP distance to Dehradun is ~6,962 km (long path), ~2,455 (short path). observations suggest that morning (TTM) forms due mode transitions both receiver transmitter for short...
The present experiment entitled "Effect of Foliar Application Humic Acid on Growth, Yield and Quality Okra (Abelmoschus esculentus L.)" was undertaken at Horticulture Research Farm, Department Horticulture, Chandra Bhanu Gupta Agriculture Post Graduate College, Bakshi Ka Talab, Lucknow during Kharif season 2023 & 24. study consisted for six treatments levels (control, 0, 5, 10, 15, 20 ml/l). laid out in Randomized Block Design replicated three times. results revealed that significantly...
[1] Observations of tweeks with higher harmonics (n > 1) at low latitude stations Allahabad and Nainital, in the Indian sector, during total solar eclipse on 22 July 2009, are presented. Nainital were 100% 85% totality paths. suggest that about 30–40% obscuration disc can lead to occurrence which otherwise occur only nighttime. A 148 20 recorded some them up 3rd harmonics. The World Wide Lightning Location Network data indicated observed generated by lightning's located partial area...
Abstract We present first report on the periodic wave‐like signatures (WLS) in D region ionosphere during 22 July 2009 total solar eclipse using JJI, Japan, very low frequency (VLF) navigational transmitter signal (22.2 kHz) observations at stations, Allahabad, Varanasi and Nainital Indian Sector, Busan Korea, Suva Fiji. The amplitude increased by about 6 7 dB Allahabad decreased 2.7, 3.5, 0.5 Nainital, Busan, Suva, respectively, as compared to 24 (normal day). increase/decrease can be...
Abstract D region effects of the 17–19 March 2015, a St Patrick's Day super geomagnetic storm ( Dst = −223 nT), using navigational transmitter very low frequency (VLF) signal (NWC, 19.8 kHz) recorded at low‐latitude Indian station, Allahabad (geomag. lat., 16.45°N), have been analyzed and compared with similar strength 22–25 June 2015 −204 nT). During storm, NWC amplitude decreased on 17 (main phase storm) recovered 27 March, which is 1 day after recovery whereas for VLF 2 days only during...
Abstract We estimate D region changes due to 22 July 2009 total solar eclipse (SE), 13–14 November 2012 SE, and 9–10 May 2013 annular using VLF navigational transmitters signal observations at Suva, Fiji. The North West Cape (NWC) (19.8 kHz) showed an amplitude phase decrease of 0.70 dB 23° during SE 2.0 90° SE. modeling Long Wave Propagation Capability code for NWC‐Suva path SEs increase in average reflection height ( H ′) sharpness factor β ) by 0.6 0.5 km 0.012 0.015 −1 , respectively....
The subject of pre-earthquake ionospheric signatures has always been contentious and debatable. Some the previous reports have documented unforeseen unusual variations in some atmospheric parameters well before an earthquake. Here, we analyze response from Indian Subcontinent to Nepal Gorkha Earthquakes occurred between April May 2015, which were most powerful disastrous natural calamities past ~80 years over Himalayan region left ~9000 causalities more than ~20000 people injured with...
Abstract. The present study reports the VLF (very low frequency) sub-ionospheric perturbations observed on transmitter JJI (22.1 kHz), Japan, received at Indian low-latitude station, Allahabad ( geographic lat. 25.41° N, long 81.93° E), due to Wenchuan earthquake (EQ) that occurred 12 May 2008 with magnitude 7.9 and depth of 19 km in Sichuan province Southwest China, located 31.0° 103.4° E. nighttime amplitude fluctuation analysis gives a significant increase dispersion two days before EQ,...
Abstract The quantity and accuracy of satellite-geodetic measurements have increased over time, revolutionizing the monitoring tectonic processes. Global Navigation Satellite System (GNSS) satellite radar signals provide observations beyond ground deformation, including how earthquake tsunami processes affect variations in ionosphere. Here, we study Hunga Tonga Ha’apai (HTHH) volcanic eruption 2022 its associated propagation with analysis GNSS derived Total Electron Content (TEC), Synthetic...
Abstract To unravel the relationship between earthquake and tsunami using ionospheric total electron content (TEC) changes, we analyzed two Chilean tsunamigenic subduction earthquakes: 2014 Pisagua M w 8.1 2015 Illapel 8.3. During earthquake, TEC changes were detected at GPS sites located to north south of epicenter, whereas during registered only in northward direction. Tide-gauge mimicked propagation direction waves similar change pattern both earthquakes. The represented by three signals....
The influence of the South American total solar eclipse 14th December 2020 on ionosphere is studied by using continuous Chilean Global Positioning System (GPS) sites across totality path. path with magnitude 1.012 passed through Villarrica (Lon. 72.2308°W and Lat. 39.2820°S) in south Chile during 14:41:02.0 UTC to 17:30:58.1 maximum occurred ~ 16:03:49.5 around local noon. vertical electron content (VTEC) derived GPS for two PRN's 29 31 show almost 20-40% reduction reference ambient values....
A total of 19,308 tweeks recorded during April 2007 to March 2008, at Allahabad, a low‐latitude station in the Indian sector, has been used study seasonal occurrence which shows maximum tweek about 63% summer season and 19% 18% occurrences equinox winter seasons. Maximum is consistent with larger number lightnings detected by World Wide Lightning Location Network Asia Oceania regions as compared that winter. Seasonally, (ionospheric) reflection height premidnight (18:00‐00:00 LT) less...
Abstract The impact of total solar eclipse July 2, 2019 on the Ionosphere is studied using 24 Chilean GPS stations north–south totality path. passed through Coquimbo region from ~ 16:38 CLT (~ 20:38 UTC) to 16:40 20:40 and maximum was observed 16:39 20:39 UTC). electron content (TEC) derived signals shows peculiar features. At TEC variations are small 0.39 TECu), but it significant decrease (maximum 2.24 TECu) for located south increase 3.89 north surface. wavelet analysis VTEC timeseries...
Interplanetary (IP) shocks are mainly responsible for the sudden compression of magnetosphere, causing storm commencement (SC) and impulses (SIs) which detected by ground‐based magnetometers. On basis list 222 IP compiled Gopalswamy et al. (2010), we have investigated dependence SC/SIs amplitudes on speed coronal mass ejections (CMEs) that drive near Sun as well in interplanetary medium. We find about 91% were associated with SC/SIs. The average SC/SI‐associated CMEs is 1015 km/s, almost a...