The Thermosphere Is a Drag: The 2022 Starlink Incident and the Threat of Geomagnetic Storms to Low Earth Orbit Space Operations by T. E. Berger, M. Dominique, G. Lucas, M. Pilinski, V. Ray, R. Sewell, E. K. Sutton, J. P. Thayer, E. Thiemann

“…We use empirical model (NRLMSIS, JB08, and HASDM) outputs as well as solar extreme ultraviolet occultation and high‐fidelity accelerometer data to show that thermospheric density was at least 20%–30% higher at 210 km relative to the 9 days prior to the launch due to consecutive geomagnetic storms related to solar eruptions from NOAA AR12936 on 29 January 2022. …”
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A New Global Ionospheric Electron Density Model Based on Grid Modeling Method by Huijun Le, Tingwei Han, Qiaoling Li, Libo Liu, Yiding Chen, Hui Zhang

“…Abstract Based on nearly 4.6 million radio occultation (RO) ionospheric profile data from Constellation Observing System for Meteorology, Ionosphere, and Climate satellites in 2006–2020, a global three‐dimensional ionospheric electron density model was constructed with a new concept. …”
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A Global Empirical Model of Electron Density Profile in the F Region Ionosphere Basing on COSMIC Measurements by Qiaoling Li, Libo Liu, Maosheng He, He Huang, Jiahao Zhong, Na Yang, Man‐Lian Zhang, Jinzhe Jiang, Yiding Chen, Huijun Le, Jun Cui

“…In this study, a high precision Ne profile model, named α‐Chapman Based Electron Density Profile Model (α‐Chapman‐Based‐EDP), was built by using ∼4.5 million Ne profiles from the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC‐1) radio occultations. We first describe each of the profiles using five parameters of the α‐Chapman function, that is, peak density (NmF2) and height (hmF2) of F2 layer, scale height (Hm) as well as its altitude change rates, and then built a model for each of the parameters as a function of latitude, longitude, month, local time, and solar activity, through Empirical orthogonal function (EOF) analysis and Fourier expansion. …”
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Permanence et mutations de l’élevage pastoral dans les Alpes du Sud by Laurent Garde, Marc Dimanche, Jacques Lasseur

“…La perception de la permanence d’une activité vue comme traditionnelle ne doit cependant pas occulter l’ampleur des mutations qui l’ont affecté dans le passé. …”
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The Potential for Observing African Weather with GNSS Remote Sensing by Olalekan A. Isioye, Ludwig Combrinck, Joel O. Botai, Cilence Munghemezulu

“…The benefit of using spaced based GNSS radio occultation (RO) data for atmospheric sounding is highlighted and filling of geographical gaps from the station-based observation network with GNSS RO is also proposed.…”
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Impact of 21 June 2020 Annular Solar Eclipse on Meteorological Parameters, O3 and CO at a High Mountain Site in Taiwan by Saginela Ravindra Babu, Shantanu Kumar Pani, Chang-Feng Ou-Yang, Neng-Huei Lin

“…A significant decrease in UV-B and solar irradiance at LABS was observed during the peak phase of the solar eclipse due to the occultation of the Sun by the Moon. On the eclipse day, the T decreased significantly (~4°C) after 17 minutes of maximum solar darkening. …”
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Modeling TEC Maps Over China Using Particle Swarm Optimization Neural Networks and Long‐Term Ground‐Based GPS, COSMIC, and Fengyun Data by Shuangshuang Shi, Kefei Zhang, Jiaqi Shi, Andong Hu, Dongsheng Zhao, Zhongchao Shi, Peng Sun, Huajing Wu, Suqin Wu

“…The new model is developed using a hybrid method composed of the particle swarm optimization (PSO) and artificial neural network and long‐term observations from 257 ground‐based global navigation satellite systems (GNSS) stations and space‐borne GNSS radio occultation systems (COSMIC and Fengyun) during the 14‐year period of 2008–2021. …”
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Application of a Multi‐Layer Artificial Neural Network in a 3‐D Global Electron Density Model Using the Long‐Term Observations of COSMIC, Fengyun‐3C, and Digisonde by Wang Li, Dongsheng Zhao, Changyong He, Yi Shen, Andong Hu, Kefei Zhang

“…In this study, multiple observations during 2005–2019 from space‐borne global navigation satellite system (GNSS) radio occultation (RO) systems (COSMIC and FY‐3C) and the Digisonde Global Ionosphere Radio Observatory are utilized to develop a completely global ionospheric three‐dimensional electron density model based on an artificial neural network, namely ANN‐TDD. …”
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Storm‐Time Modeling of the African Regional Ionospheric Total Electron Content Using Artificial Neural Networks by Daniel Okoh, John Bosco Habarulema, Babatunde Rabiu, Gopi Seemala, Joshua Benjamin Wisdom, Joseph Olwendo, Olivier Obrou, Tshimangadzo Merline Matamba

“…To increase data coverage in areas devoid of ground‐based instrumentation including oceans, we used the available radio occultation Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) TEC from 2008 to 2018. …”
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To Link Life Histories to Historical Narratives by Irène Dos Santos

“…Au Portugal la mémoire officielle de l’empire a jusqu’à très récemment occulté les passés violents plus récents de la dictature et de la décolonisation (guerre coloniale, rapatriement) moins fédérateurs pour l’identité collective. …”
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3‐D Regional Ionosphere Imaging and SED Reconstruction With a New TEC‐Based Ionospheric Data Assimilation System (TIDAS) by Ercha Aa, Shun‐Rong Zhang, Philip J. Erickson, Wenbin Wang, Anthea J. Coster, William Rideout

“…Abstract A new TEC‐based ionospheric data assimilation system (TIDAS) over the continental US and adjacent area (20°–60°N, 60°–130°W, and 100–600 km) has been developed through assimilating heterogeneous ionospheric data, including dense ground‐based Global Navigation Satellite System (GNSS) Total Electron Content (TEC) from 2,000+ receivers, Constellation Observing System for Meteorology, Ionosphere, and Climate radio occultation data, JASON satellite altimeter TEC, and Millstone Hill incoherent scatter radar measurements. …”
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Performance Analysis of a Strong Constraint 4DVar and 4DEnVar on Regional Ionosphere Imaging by Nicholas Ssessanga, Wojciech Jacek Miloch, Lasse Boy Novock Clausen, Daria Kotova

“…Verification of reconstructions is with independent observations from ground‐based ionosonde and satellite radio occultations: the performance of both schemes is fairly adequate during the quiet period when the background has a better estimation of the hmF2. …”
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Analysis of Radio Science Data from the KaT Instrument of the 3GM Experiment During JUICE’s Early Cruise Phase by Paolo Cappuccio, Andrea Sesta, Mauro Di Benedetto, Daniele Durante, Umberto De Filippis, Ivan di Stefano, Luciano Iess, Ruaraidh Mackenzie, Bernard Godard

“…The 3GM experiment employs a Ka-band Transponder (KaT) to enable two-way coherent range and Doppler measurements used for the gravity experiment and an Ultra Stable Oscillator (USO) for one-way downlink occultation experiments. This paper analyzes KaT data collected at the ESA/ESTRACK ground station in Malargüe, Argentina, during the Near-Earth Commissioning Phase (NECP) in May 2023 and the first in-cruise payload checkout (PC01) in January 2024. …”
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Validation of the version 4.5 MAESTRO ozone and NO₂ measurements by P. S. Jeffery, J. R. Drummond, C. T. McElroy, K. A. Walker, J. Zou

“…<p>Launched aboard the Canadian SCISAT satellite in August 2003, the Measurement of Aerosol Extinction in the Stratosphere and Troposphere Retrieved by Occultation (MAESTRO) instrument has been measuring solar absorption spectra in the ultraviolet (UV) and visible part of the spectrum for more than 20 years. …”
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