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Variations of thermosphere Density Based on Joint Analysis of In-Situ Measurement Data From Shenzhou Spacecrafts

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空间科学学报 2012年第2期32卷 216-222页

作者： SUN Lilin QIN Guotai ZHU Guangwu Center for Space Science and Applied Research Chinese Academy of SciencesBeijing 100190 Graduate University of Chinese Academy of Sciences Beijing 100049

Based on the measurements made by Atmospheric Density Detectors(ADDs) onboard Chinese spacecraft Shenzhou 2-4,the variations of thermosphere density are *** the quiet period,the density at spacecraft altitude of 330~410 km exhibited a dominant diurnal variation,with high value on dayside and low value on *** ratio of the diurnal maximum density to the minimum ranged from 1.7 to *** ratio shows a positive correlation with the level of solar activity and a negative correlation with the level of geomagnetic *** a geomagnetic disturbance comes,the atmospheric density at the altitude of 330～410 km displayed a global *** a strong geomagnetic disturbance,the atmospheric density increased by about 56%,and reached its maximum about 6～7 hours after the geomagnetic disturbance peak. The density asymmetry was also observed both in the southern and northern hemisphere during the geomagnetic disturbance peak.

关键词： thermosphere Atmospheric density Solar activity Geomagnetic disturbance

An Introduction to Magnetosphere-Ionosphere-thermosphere Coupling Small Satellite Constellation

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空间科学学报 2015年第6期35卷 653-663页

作者： LIU Yong WANG Chi XU Jiyao LI Xiaoyu CAI Jinrong KONG Linggao HUANG Jia KLECKER Berndt LEI Jiuhou ZONG Qiugang OCTAV Marghitu State Key Laboratory of Space Weather National Space Science CenterChinese Academy of Sciences Beijing Key Laboratory of Space Environment Exploration National Space Science Center Chinese Academy of Sciences Max-Planck-Institut für Extraterrestrische CAS Key Laboratory of Geospace Environment Department of Geophysics and Planetary SciencesUniversity of Science and Technology of China Institute of Space Physics and Applied Technology School of Earth and Space SciencesPeking University National Institute for Lasers Plasma and Radiation Physics Institute for Space Sciences

A future Chinese mission is introduced to study the coupling between magnetosphere,ionosphere and thermosphere,*** Magnetosphere-Ionosphere-thermosphere Coupling Small Satellite Constellation(MIT).The scientific objective of the mission is to focus on the outflow ions from the ionosphere to the *** constellation is planning to be composed of four small satellites;each small satellite has its own orbit and crosses the polar region at nearly the same time but at different *** payloads onboard include particle detectors,electromagnetic payloads,auroral imagers and neutral atom *** these payloads,the mission will be able to investigate acceleration mechanism of the upflow ions at different *** the orbits have been determined and prototypes of some have also been *** for next phase selection is scheduled in late 2015.

关键词： Coupling Magnetosphere Ionosphere thermosphere Sma

Climatological modeling of horizontal winds in the mesosphere and lower thermosphere over a mid-latitude station in China

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Climatological modeling of horizontal winds in the mesospher...

Effects of estimating the ionospheric and thermospheric parameters on electron density forecasts

中国科学院地质与地球物理研究所2015年度（第15届）...

作者： Xin Yao Tao Yu Biqiang Zhao You Yu Libo Liu Baiqi Ning Weixing Wan Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of Sciences Beijing National Observatory of Space Environment Institute of Geology and GeophysicsChinese Academy of Sciences University of Chinese Academy of Sciences Institute of Geophysics and Geomatics China University of Geosciences National Center for Space Weather China Meteorological Administration

In this study,we employed the non-uniform rational B-splines surface technique to develop a provisional horizontal wind model of the mesosphere and lower thermosphere at altitudes of 87,97,and 250 km over Kelan(38.7°N,111.6°E) in China using Fabry–Perot interferometer(FPI) observations for the period between January 2012 and May *** compared the meridional and zonal winds derived from the Kelan FPI wind model with those based on Meteor Radar wind observations at Beijing(39.92°N,116.39°E),and those calculated from horizontal wind models,i.e.,HWM93 and HWM07,at *** analysis showed the following.(1) At 87 and 97 km,the Kelan FPI wind patterns exhibited strong annual variation in the meridional wind and semiannual variation in the zonal wind,as well as diurnal variation,which was dominated by a semidiurnal tidal variation in the meridional and zonal winds during May and September with a diurnal phase *** Kelan FPI wind patterns agreed well with the Meteor Radar winds and the HWM07 model results,but less well with the HWM93 model.(2) At 250 km,the FPI wind patterns agreed fairly well with the HWM93 results,where both indicated annual/diurnal variation in the meridional and zonal winds,and weak semidiurnal tidal *** were large discrepancies between the Kelan FPI winds and the HWM07 model results,which were mainly due to differences in the annual variation in the nighttime meridional wind.(3) The magnitude of the FPI winds was comparable to the HWM93 results but they were nearly 40–50% lower than the other winds,which is attributable to the inherent limitations of airglow ***,this local empirical wind model could be used to investigate the climatological features of local ionospheric spatial–temporal variations.

关键词： Fabry–Perot interferometer Horizontal wind model thermosphere

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Science China Earth Sciences 2018年第12期61卷 1875-1887页

作者： Yanan ZHANG Xiaocheng WU Xiong HU National Space Science Center Chinese Academy of Sciences University of Chinese Academy of Sciences

Based on the thermosphere-Ionosphere-Electrodynamics General Circulation Model(TIEGCM), a thermosphericionospheric data assimilation and forecast system is developed. Using this system, we estimated the oxygen ions, neutral temperature, wind, and composition by assimilating the simulated data from Formosa Satellite 3/Constellation Observing System for Meteorology, Ionosphere, and Climate(COSMIC) occultation electron density profiles to evaluate their effects on the ionospheric forecast. An ensemble Kalman filter data assimilation scheme and combined state and parameter estimation methods are used to estimate the unobserved parameters in the model. The statistical results show that the neutral and ion compositions are more effective than the neutral temperature and wind for improving the forecast of the ionospheric electron density, whose root mean square errors in the assimilation period decreased by approximately 40%, 30%, and 10% due to the estimations of the neutral composition, oxygen ions, and neutral temperature, respectively. Due to the different physical and chemical processes that these parameters primarily affect, their e-folding times differ greatly from longer than 12 h for neutral composition to approximately 6 h for oxygen ions and 3 h for neutral temperature. The effect of estimating the neutral composition on improving the ionospheric forecast is greater than that of estimating the oxygen ions, which can be also be seen in an actual data assimilation experiment. This indicates that the neutral composition is the most important thermospheric parameter in ionospheric data assimilations and forecasts.

关键词： Electron density Ionosphere thermosphere Data assimilation Ensemble Kalman filter

Interaction between Equatorial Plasma Bubbles and a Medium-Scale Traveling Ionospheric Disturbance,observed by OI 630 nm airglow imaging at Bom Jesus de Lapa,Brazil

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Earth and Planetary Physics 2021年第5期5卷 397-406页

作者： Cristiano Max Wrasse Cosme Alexandre Oliveira Barros Figueiredo Diego Barros Hisao Takahashi Alexander JoséCarrasco Luiz Fillip Rodrigues Vital Láysa Cristina Araujo Resende Fábio Egito Geângelo de Matos Rosa Antonio Hélder Rodrigues Sampaio Space Weather Division National Institute for Space Research(INPE)São Josédos CamposBrazil University of Los Andes(ULA) MéridaVenezuela State Key Laboratory of Space Weather Beijing 100190China Federal University of Campina Grande(UFCG) Campina GrandeBrazil Federal Institute for Education Science and Technology Baiano(IF Baiano)Bom Jesus da LapaBrazil

OI 630.0 nm airglow observations,from a new observatory at Bom Jesus de Lapa,were used to study the interaction between EPBs(Equatorial Plasma Bubbles)and the MSTID(Medium-Scale Traveling Ionospheric Disturbance)over the Northeast region in *** the night of September 16 to 17,2020,an EPB was observed propagating eastward,in an apparent fossil stage,until it interacted with a dark band electrified MSTID(e MSTID).After the interaction,four EPBs merged,followed by an abrupt southward development and *** of the data suggests that an eastward polarization electric field,induced by the dark band e MSTID,forced the EPB into an upward drift,growing latitudinally along the magnetic field lines and then bifurcating.

关键词： Equatorial Plasma Bubbles Medium-Scale Traveling Ionospheric Disturbance ionosphere thermosphere EPB and MSTID interaction

Thermospheric mass density measurement from precise orbit ephemeris

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Geodesy and Geodynamics 2016年第3期7卷 210-215页

作者： Junyu Chen Jizhang Sang School of Geodesy and Geomatics Wuhan University Wuhan 430079 China Collaborative Innovation Center for Geospatial Technology Wuhan 430079 China

Atmospheric drag, which can be inferred from orbit information of low-Earth orbiting （LEO） satellites, provides a direct means of measuring mass density. The temporal resolution of derived mass density could be in the range from minutes to days, depending on the pre- cision of the satellite orbit data. This paper presents two methods potentially being able to estimate thermosphere mass density from precise obit ephemeris with high temporal resolution. One method is based on the drag perturbation equation of the semi-major axis and the temporal resolution of retrieved density could be ~lB0 s for CHAMP satellite. Another method generates corrections to densities computed from a baseline density model through a Kalman filter orbit drag coefficient determination （KFOD） process and the temporal resolution of derived density could be as high as 30 s for CHAMP satellite. The densities estimated from these two methods are compared with densities obtained from accelerometer data of CHAMP satellite. When the accelerometer data based densities are used as reference values, the mean relative accuracy of the densities derived from precision orbit data using the two methods is within approximately 10%. An application of the derived densities shows that the derived densities can reduce orbit predication errors.

关键词： thermosphere Mass density Kalman filter Accelerometer

Formation of Ionospheric Precursors of Earthquakes—Probable Mechanism and Its Substantiation

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Open Journal of Earthquake Research 2020年第2期9卷 142-169页

作者： Georgii Lizunov Tatiana Skorokhod Masashi Hayakawa Valery Korepanov Space Research Institute Kyiv Ukraine Hayakawa Institute of Seismo Electromagnetics Co. Ltd. Tokyo Japan Lviv Center of Institute for Space Research Lviv Ukraine

The purpose of this article is to attract the attention of the scientific community to atmospheric gravity waves (GWs) as the most likely mechanism for the transfer of energy from the surface layers of the atmosphere to space heights and describe the channel of seismic-ionospheric relations formed in this way. The article begins with a description and critical comparison of several basic mechanisms of action on the ionosphere from below: the propagation of electromagnetic radiation;the closure of the atmospheric currents through the ionosphere;the penetration of waves throughout the neutral atmosphere. A further part of the article is devoted to the analysis of theoretical and experimental information relating to the actual GWs. Simple analytical expressions are written that allow one to calculate the parameters of GWs in specific experimental situations. Specificity of GW dispersion properties and features of their propagation are analyzed on this mathematical basis, processes of amplitude amplification and dissipation of GWs with height are investigated, the mechanism of generation of ionosphere-magnetosphere current systems is described and their quantitative characteristics are determined. The experimental part presents an analysis of GWs global distribution in the thermosphere derived from the data of the instrument NACS (Neutral Atmosphere Composition Spectrometer) onboard the satellite DE-2 (NASA, 1981-1983). The statistical association of registered ionospheric disturbances with earthquakes is demonstrated. The results of DE-2 data processing are backed up by comparison with data from the DEMETER satellite (CNES, 2005-2010) whose purpose was to study the ionospheric effects of earthquakes. Specific features of GWs that characterize these waves as a factor of influence on the ionosphere from below are indicated.

关键词： Atmospheric Gravity Waves Seismic-Ionospheric Coupling thermosphere