Articles | Volume 39, issue 4
https://doi.org/10.5194/angeo-39-743-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/angeo-39-743-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Climatology of ionosphere over Nepal based on GPS total electron content data from 2008 to 2018
Drabindra Pandit
CORRESPONDING AUTHOR
Central Department of Physics, IOST, Tribhuvan University, Kathmandu, Nepal
Department of Physics, St. Xavier's College, Maitighar, Kathmandu, Nepal
Basudev Ghimire
Central Department of Physics, IOST, Tribhuvan University, Kathmandu, Nepal
Department of Physics, St. Xavier's College, Maitighar, Kathmandu, Nepal
Christine Amory-Mazaudier
Sorbonne Université, Ecole polytechnique, Institut Polytechnique de
Paris, Université Paris Saclay, Observatoire de Paris, CNRS, Laboratoire
de Physique des Plasmas (LPP), 75005 Paris, France
T/ICT4D, Abdus Salam ICTP, Trieste, Italy
Rolland Fleury
Lab-STICC, UMR 6285, Institut Mines-Télécom Atlantique, Brest, France
Narayan Prasad Chapagain
Department of Physics, Amrit Campus, Tribhuvan University, Thamel, Kathmandu, Nepal
Binod Adhikari
Department of Physics, St. Xavier's College, Maitighar, Kathmandu, Nepal
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The electrical inductions within the Earth surface due to geomagnetic field variations were examined. For that purpose the records of the geomagnetic and geo-electric field variations observed in West Africa were used. We have found that the geomagnetic field brisk variations induce non-negligible geo-electric field variations at low latitudes. This result implies a possible intense geomagnetically induced current flow in the vicinity of the equatorial electrojet influence area.
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Subject: Earth's ionosphere & aeronomy | Keywords: Climatology of the ionosphere
Global total electron content prediction performance assessment of the IRI-2016 model based on empirical orthogonal function decomposition
Climatology of intermediate descending layers (or 150 km echoes) over the equatorial and low-latitude regions of Brazil during the deep solar minimum of 2009
Shuhui Li, Jiajia Xu, Houxiang Zhou, Jinglei Zhang, Zeyuan Xu, and Mingqiang Xie
Ann. Geophys., 38, 331–345, https://doi.org/10.5194/angeo-38-331-2020, https://doi.org/10.5194/angeo-38-331-2020, 2020
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The empirical orthogonal function (EOF) decomposition was utilized to analyze the similarities and differences of the spatiotemporal characteristics between GIM TEC and IRI TEC at a global scale. We combined the IRI TEC and GIM TEC data to form a whole data set for EOF decomposition and compared the two data sets. Results show that the daily averaged solar forcing and interhemispheric asymmetry components were the main factors for the deviation between the IRI-2016 and GIM TEC.
Ângela Machado dos Santos, Inez Staciarini Batista, Mangalathayil Ali Abdu, José Humberto Andrade Sobral, Jonas Rodrigues de Souza, and Christiano Garnett Marques Brum
Ann. Geophys., 37, 1005–1024, https://doi.org/10.5194/angeo-37-1005-2019, https://doi.org/10.5194/angeo-37-1005-2019, 2019
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For the first time, the climatology of intermediate descending layers (~150 km) over Brazilian equatorial and low-latitude regions during the extreme solar minimum period of 2009 was investigated. The results are interesting and innovative. For this analysis we used data of height and top frequency of intermediate layers collected from a digisonde located at São Luis and Cachoreira Paulista.
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Short summary
We analyse the climatology of the ionosphere over Nepal based on GPS-derived vertical total electron content (VTEC) during 2008–2018. The study illustrates the diurnal, monthly, annual, seasonal and solar cycle variations in VTEC. The results show equinoctial asymmetry in TEC in maximum phases in 2014, followed by descending, ascending and minimum phases. The winter anomalies are seen during increasing and maximum phases of the solar cycle (2011–2014) from almost all stations considered.
We analyse the climatology of the ionosphere over Nepal based on GPS-derived vertical total...