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Quasi-stationary planetary waves in the middle atmosphere of Mars

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Science China Earth Sciences 2015年第2期58卷 309-316页

作者： WANG NingNing LI Tao dou xiankang CAS Key Laboratory of Geospace Environment Department of Geophysics and Planetary Science University of Science and Technology of China Mengcheng National Geophysical Observatory School of Earth and Space ScienceUniversity of Science and Technology of China

Using the temperature profiles retrieved from the Mars Climate Sounder（MCS） instrument onboard Mars Reconnaissance Orbiter（MRO） satellite between November 2006 and April 2013, we studied the seasonal and interannual variability of QuasiStationary Planetary Waves（QSPWs） in the Martian middle atmosphere. The QSPW amplitudes in the Southern Hemisphere（SH） high latitudes are significantly stronger than those in the Northern Hemisphere（NH）. Seasonal variation with maximum amplitude near winter solstice of each hemisphere is clearly seen. The vertical structure of the QSPW in temperature shows double-layer feature with one peak near 50 Pa and the other peak near 1 Pa. The QSPW in geopotential height is clearly maximized in the region between two temperature peaks. The maximum amplitude of QSPW for s=1 is ~8–10 K in temperature and ~1 km in geopotential height in the SH high latitudes. The maximum amplitude at the SH high latitudes in Mars Year（MY） 31 is ~2 K stronger than those in other MYs, suggesting the clear interannual variability. We compared the satellite results with those obtained from the Mars Climate Database（MCD） simulation version 5.0; a reasonable agreement was found. The MCD simulation further suggested that the variability of dust might partially contribute to the interannual variability of QSPW amplitude.

关键词： interannual planetary winter seasonal stationary stronger latitude hemisphere altitude reconstructed

Inertial gravity waves observed by a Doppler wind LiDAR and their possible sources

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Earth and Planetary Physics 2020年第5期4卷 461-471页

作者： XiangHui Xue DongSong Sun HaiYun Xia xiankang dou Chinese Academy of Sciences Key Laboratory of Geospace Environment University of Science and Technology of ChinaHefei 230026China Chinese Academy of Sciences Center for Excellence in Comparative Planetology Hefei 230026China Anhui Mengcheng Geophysics National Observation and Research Station University of Science and Technology of China Hefei 230026China Synergetic Innovation Center of Quantum Information&Quantum Physics University of Science and Technology of ChinaHefei 230026China Hefei National Laboratory for the Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China

In this paper,we use wind observations by a Doppler wind LiDAR near Delingha(37.4°N,97.4°E),Qinghai,Northwestern China to study the characteristics of inertial gravity waves in the *** focus on 10–12 December 2013,a particularly interesting case *** of the time,the inertial gravity waves extracted from the LiDAR measurements were stationary with vertical wavelengths of about 9–11 km and horizontal wavelengths of about 800–1000 ***,for parts of the observational period in this case study,a hodograph analysis indicates that different inertial gravity wave propagation features were present at lower and upper *** the middle and upper stratosphere(~30–50 km),the waves propagated downward,especially during a period of stronger winds,and to the northwest–*** the lower stratosphere and upper troposphere(~10–20 km),however,waves with upward propagation and northeast–southwest orientation were *** taking into account reanalysis data and satellite observations,we have confirmed the presence of different wave patterns in the lower and upper stratosphere during this part of the observational *** combined data sets suggest that the different wave patterns at lower and upper height levels are likely to have been associated with the presence of lower and upper stratospheric jet streams.

关键词： gravity waves lidar wind observations

COSMIC GPS observations of topographic gravity waves in the stratosphere around the Tibetan Plateau

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Science China Earth Sciences 2017年第1期60卷 188-197页

作者： ZENG XuanYun XUE XiangHui dou xiankang LIANG Chen JIA MingJiao Chinese Academy of Sciences Key Laboratory of Geospace Environment School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China

Temperature profiles provided by the Constellation Observing System for Meteorology, Ionosphere and Climate （COSMIC） global positioning system （GPS） satellite constellation were used to study an eight-year series （2007 to 2015） of gravity wave （GW） potential energy in the stratosphere （18-30 kin） around the Tibetan Plateau （TP）. We found that with increasing altitude, the GW potential energy （Ep） values in the stratosphere caused by convection decreases. The importance of GWs that are stimulated by topography is enhanced in this area. In the TP, which was considered to lack strong topographical GW activity, clear activity existed in the spring and winter of all studied years. Based on the latitudinal zone of the TP, the distribution of GW potential energy is highly consistent with the elevation of the local topography. The activities of topographical GWs are strongly filtered as they propagate upward to the area of zero speed wind. The analysis indicates that in the TP, clear orographic GW excitation exists and propagates upward to the upper stratosphere, where it is greatly influenced by the wind.

关键词： Tibetan Plateau Gravity wave Stratosphere Topography Filtering of wind

Thermospheric mass density derived from CHAMP satellite precise orbit determination data based on energy balance method

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Science China Earth Sciences 2017年第8期60卷 1495-1506页

作者： LI RuoXi LEI JiuHou WANG XiJing dou xiankang JIN ShuangGen School of Earth and Space Science University of Science and Technology China Key Laboratory for Fault Diagnosis and Maintenance of Spacecraft In-orbit Shanghai Astronomical Observatory Chinese Academy of Sciences

In this article, the energy balance method is used to retrieve thermospheric mass density from CHAMP satellite precise orbit determination(POD) data during 2007–2009. The retrieved thermospheric mass densities are compared with those from accelerometer data and an empirical model. The main conclusions are as follows:(1) Thermospheric mass density can be retrieved from POD data by the energy balance and semi-major axis decay methods, whose results are consistent.(2) The accuracy of the retrieved densities depends on the integration time period, and the optimal period for CHAMP density retrieval from POD data is about 20 minutes.(3) The energy balance method can be used to calibrate accelerometer data.(4) The accuracy of retrieving thermospheric density from POD data varies with satellite altitude and local time.

关键词： Thermospheric mass density Satellite orbit Semi-major axis Energy balance Accelerometer

Reponses of middle atmospheric circulation to the 2009 major sudden stratospheric warming

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Earth and Planetary Physics 2020年第5期4卷 472-478页

作者： ShengYang Gu Xin Hou JiaHui Qi KeMin TengChen xiankang dou School of Electronic Information Wuhan UniversityWuhan 430072China

In this research, the roles of gravity waves and planetary waves in the change to middle atmospheric residual circulation duringa sudden stratospheric warming period are differentiated and depicted separately by adopting the downward control principle. Ouranalysis shows clear anomalous poleward residual circulation patterns from the equator to high latitudes in the lower winterstratosphere. At the same time, upward mean flows are identified at high latitudes of the winter upper stratosphere and mesosphere,which turn equatorward in the mesosphere and reach as far as the tropical region, and consequently the extratropical region in thesummer hemisphere. The downward control principle shows that anomalous mesospheric residual circulation patterns, includinginterhemispheric coupling, are solely caused by the change in gravity wave forcing resulting from the reversal of the winter stratosphericzonal wind. Nevertheless, both planetary waves and gravity waves are important to variations in the winter stratospheric circulation, butwith opposite effects.

关键词： sudden stratospheric warming residual circulation gravity and planetary waves

Assessment of International GNSS Service Global Ionosphere Map products over China region based on measurements from the Crustal Movement Observation Network of China

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Earth and Planetary Physics 2024年第2期8卷 400-407页

作者： Jin Hu HaiBing Ruan FuQing Huang ShengYang Gu xiankang dou Institute of Space Weather Nanjing University of Information Science and TechnologyNanjing 210044China State Key Laboratory of Space Weather Chinese Academy of Sciences(CAS)Beijing 100190China School of Electronic Information Wuhan UniversityWuhan 430072China Wuxi Research Institute Nanjing University of Information Science and TechnologyWuxi Jiangsu 214000China CAS Key Laboratory of Geospace Environment School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China

The global ionosphere maps(GIM)provided by the International GNSS Service(IGS)are extensively utilized for ionospheric morphology monitoring,scientific research,and practical *** the credibility of GIM products in data-sparse regions is of paramount *** this study,measurements from the Crustal Movement Observation Network of China(CMONOC)are leveraged to evaluate the suitability of IGS-GIM products over China region in *** indices of mean error(ME),root mean square error(RMSE),and normalized RMSE(NRMSE)are then utilized to quantify the accuracy of IGS-GIM *** revealed distinct local time and latitudinal dependencies in IGS-GIM errors,with substantially high errors at nighttime(NRMSE:39%)and above 40°latitude(NRMSE:49%).Seasonal differences also emerged,with larger equinoctial deviations(NRMSE:33.5%)compared with summer(20%).A preliminary analysis implied that the irregular assimilation of sparse IGS observations,compounded by China’s distinct geomagnetic topology,may manifest as error *** results suggest that modeling based solely on IGS-GIM observations engenders inadequate representations across China and that a thorough examination would proffer the necessary foundation for advancing regional total electron content(TEC)constructions.

关键词： International GNSS Service(IGS)Global Ionosphere Maps(GIM) Crustal Movement Observation Network of China(CMONOC) total electron content(TEC) data assessment

Semiannual oscillation,annual oscillation,quasibiennial oscillation,and solar cycle variation of the OH airglow emission in the mesopause region

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Earth and Planetary Physics 2024年第3期8卷 479-496页

作者： Sheng-Yang Gu Dong Wang YuSong Qin Liang Tang YaFei Wei xiankang dou Electronic Information School Wuhan UniversityWuhan 430072China School of Optoelectronic Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China

The vertically integrated emission rate,centroid altitude,peak emission rate,and peak height of the hydroxyl(OH)airglow were calculated from Thermosphere Ionosphere Mesosphere Energetics and Dynamics(TIMED)/Sounding of the Atmosphere using Broadband Emission Radiometry(SABER)observations to study the seasonal and interannual variations in the intensity and location of the OH *** emission rate is inversely proportional to the height of the emission,with the semiannual oscillation dominating at low latitudes and the annual oscillation dominating at higher *** OH emission is modulated by the quasibiennial oscillation at the equator,and the quasibiennial oscillation signal is weak at other *** represented the vertical transport of atomic oxygen by using atomic oxygen concentrations obtained from a global atmospheric model,the Specified Dynamics Whole Atmosphere Community Climate Model with thermosphere and ionosphere eXtension *** with the amplitudes of the migrating diurnal tide(DW1)calculated from temperature data observed by TIMED/SABER,we found that both the vertical transport of atomic oxygen and DW1 amplitudes in the equatorial region exhibit semiannual oscillation and quasibiennial oscillation,which have a strong correlation with the variations in the amplitude and phase of semiannual oscillation and quasibiennial oscillation in OH *** is likely that the DW1 affects the vertical transport of atomic oxygen that is involved in the reaction to produce O3,thus affecting the OH *** analyzed the relationship between OH emission and solar activity by using the solar radio flux at 10.7 cm as a proxy for solar *** results showed that the OH emission is well correlated with solar activity,and the modulation of OH emission by solar activity has a significant latitudinal *** small correlation between emission height and solar activity indicates that solar activity modulates OH emission mainly thr

关键词： OH airglow semiannual oscillation quasibiennial oscillation solar activity diurnal tide

A simulation study of 630 nm and 557.7 nm airglow variations due to dissociative recombination and thermal electrons by high-power HF heating

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Earth and Planetary Physics 2017年第1期1卷 44-52页

作者： Tong Dang JiuHou Lei xiankang dou WeiXing Wan CAS Key Laboratory of Geospace Environment School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Mengcheng National Geophysical Observatory University of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Astronautical Science and Technology Harbin 150001China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

One of the important effects of the ionospheric modification by high-power waves is the airglow enhancement. Both the thermal electrons and the dissociation recombination contribute to generate the airglow emissions during HF heating. However, the relative importance of the airglow emission induced by dissociative recombination and thermal electrons has been rarely investigated. In this study, we carry out a simulation study on the airglow produced by high-power HF heating at nighttime associated with dissociative recombination and thermal electrons. SAMI2(Sami2 is Another Model of the Ionosphere) is employed to simulate the ionospheric variations during the HF heating. The main conclusions from this study are as follows:(1) For the airglow induced by dissociative recombination, both 630.0 nm and 557.7 nm emissions show a decrease at the heating wave reflection height during the heating period,while when the heating is turned off, an increase is shown at lower altitudes. The reduction of airglow during the heating is caused by the rapid increase of electron temperature and the diffusion of plasmas dominates the after-heating airglow enhancement.(2) 630.0 nm emission due to thermal electrons is greatly enhanced at the wave reflection height, indicating that thermal electrons play a major role in exciting 630.0 nm emission. For the 557.7 nm emission, the excitation threshold(4.17 e V) is too high for thermal electrons.(3) The combined effect of dissociative recombination and thermal electrons could be the possible reason for the observed X-mode(extraordinary mode) suppression of 630.0 nm airglow during O-mode(ordinary mode) enhancement.

关键词： airglow thermal electron dissociative recombination HF heating

Cross-satellite calibration of high-energy electron fluxes measured by FengYun-4A based on Arase observations

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Earth and Planetary Physics 2023年第5期7卷 565-575页

作者： XiaoYu Wang Xing Cao Xin Ma XiaoXin Zhang AnQin Chen JunHu Dong BinBin Ni xiankang dou Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China Key Laboratory of Space Weather National Satellite Meteorological Center(National Center for Space Weather)China Meteorological AdministrationBeijing 100081China Innovation Center for FengYun Meteorological Satellite(FYSIC) National Satellite Meteorological CenterChina Meteorological AdministrationBeijing 100081China

We use the High-energy Electron Experiments(HEP)instrument onboard Arase(ERG)to conduct an energy-dependent cross-satellite calibration of electron fluxes measured by the High Energy Particle Detector(HEPD)onboard FengYun-4A(FY-4A)spanning from April 1,2017,to September 30,*** tracing the two-dimensional magnetic positions(L,magnetic local time[MLT])of FY-4A at each time,we compare the datasets of the conjugate electron fluxes over the range of 245–894 keV in 6 energy channels for the satellite pair within different sets of L×*** variations in the electron fluxes observed by FY-4A generally agree with the Arase measurements,and the percentages of the ratios of electron flux conjunctions within a factor of 2 are larger than 50%.Compared with Arase,FY-4A systematically overestimates electron fluxes at all 6 energy channels,with the corresponding calibration factors ranging from 0.67 to *** the cross-satellite calibration,the electron flux conjunctions between FY-4A and Arase show better agreement,with much smaller normalized root mean square *** results provide a valuable reference for the application of FY-4A high-energy electron datasets to in-depth investigations of the Earth’s radiation belt electron dynamics.

关键词： cross-satellite calibration high-energy electron flux FengYun-4A Arase