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Simulation of gravity wave instability and the formation of large winds and shears in the mesosphere and lower thermosphere

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Simulation of gravity wave instability and the formation of ...

Possible modulation of migrating diurnal tide by latitudinal gradient of zonal wind observed by SABER/TIMED

第十四届全国日地空间物理学术研讨会

作者： xiao {1.1, 2.{2. xu1 Han -Li liu3 Wei Yuan1 (1 state key laboratory of space weather, center for space science and applied research, Chinese Academy of sciences, {12., china, 100190) (2.College of Mathematics and Information science, Henan Normal University, Xinxiang, china) (3 High Altitude Observatory, National center for Atmospheric research, Boulder, Colorado, USA)

Large winds and wind shears in the mesosphere and lower thermosphere （MLT） region have been observed for decades and by various techniques （1.. It is necessary to investigate the causes of the large winds and wind shears （2.. A high resolution parallel numerical model is developed to simulate the propagation of gravity waves （GWs） in a compressible atmosphere. The winds and wind shears are determined by the wave perturbation, the mean flow change induced by wave breaking and/or dissipation, as well as the vertical scale of the waves. In particular, the accelerated mean winds in the direction of the GWs horizontal phase velocity decrease the GWs vertical wavelength, and increase the large wind shears. As a result, the positive feedback between GWs momentum deposition, mean wind acceleration, and the decreasing vertical wavelength induces the large wind shears in the MLT region. The comparative studies show that background temperature and the height of mesopause can affect the time and height of GWs breaking, the accelerated mean winds and total wind shears. In addition, decreasing diffusion in the numerical simulations generally increases the magnitude of mean winds and total wind shears. When GWs with different wavelengths propagate in the tidal background with different initial tidal phases, their interactions result in a strong correlation between the initial tidal phase and the large wind shears and may be responsible for the local time dependence of the occurrence of the large wind shears observed by Yue et al.（3）. Moreover, the tidal modulation effect decreases （but does not disappear） with the increasing vertical wavelength of GWs. In addition, large wind shears occur at two heights separated approximately by the vertical wavelength of the tide and just below the maximum of positive tidal wind shear for GWs with vertical wavelengths longer than 1. km.

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science{1. Earth sciences 2016年第2期59卷 408-417页

作者： liu MoHan {1. {2. liu HanLi liu xiao state {1. {2. of space weather Center for Space Science and Applied Research Chinese Academy of Sciences College of Earth science University of Chinese Academy of Sciences High Altitude Observatory National Center for Atmospheric Research College of Mathematics and Information science Henan Normal University

Temperature data from SABER/TIMED and Empirical Orthogonal Function （EOF） analysis are taken to examine possible modulations of the temperature migrating diurnal tide （DW1. by latitudinal gradients of zonal mean zonal wind （ ζ ）. The result shows that ζ increases with altitudes and displays clearly seasonal and interannual variability. In the upper meso- sphere and lower thermosphere （MLT）, at the latitudes between 2.°N and 2.°S, when ζ strengthens （weakens） at equinoxes （solstices） the DW1.amplitude increases （decreases） simultaneously. Stronger maximum in March-April equinox occurs in both ζ and the DW1.amplitude. Besides, a quasi-biennial oscillation of DW1.is also found to be synchronous with ζ. The resembling spatial-temporal features suggest that ζ in the upper tropic MLT probably plays an important role in modulating semiannual, annual, and quasi-biennial oscillations in DW1.at the same latitude and altitude. In addition, ζ in the meso- sphere possibly affects the propagation of DW1.and produces SAO of DW1.in the lower thermosphere. Thus, SAO of DW1.in the upper MLT may be a combined effect of ζ both in the mesosphere and in the upper MLT, which models studies should determine in the future.

关键词： Migrating diurnal tide Temporal variations Latitudinal gradient of zonal wind Mesosphere and lower thermo- sphere

Global static stability and its relation to gravity waves in the middle atmosphere

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Earth and Planetary Physics 2020年第5期4卷 504-512页

作者： xiao {1. {2. xu Jia Yue Henan Engineering laboratory for Big Data Statistical Analysis and Optimal Control School of Mathematics and Information SciencesHenan Normal UniversityXinxiang Henan 453007China state {1. {2. of space weather Center for Space Science and Applied ResearchChinese Academy of SciencesBeijing 100190China School of Astronomyand space {1. University of the Chinese Academy of ScienceBeijing 100049China Catholic University of America WashingtonDC 20064USA National Aeronautics and space Administration(NASA)Goddard space Flight {2. GreenbeltMD 20771USA

The global atmospheric static stability(N2.in the middle atmosphere and its relation to gravity waves(GWs)were investigated by using the temperature profiles measured by the Sounding of the Atmosphere using Broadband Emission Radiometry(SABER)instrument from 2.02.to *** low latitudes,a layer with enhanced N2.occurs at an altitude of^2. km and exhibits annual oscillations caused by tropopause inversion *** an altitude of^70 km,enhanced N2.exhibits semiannual oscillations at low latitudes caused by the mesosphere inversion layers and annual oscillations at high latitudes resulting from the downward shift of the summer *** correlation coefficients between N2.and GW amplitudes can be larger than 0.8 at latitudes poleward of^40°N/*** observation provides factual evidence that a large N2.supports large-amplitude GWs and indicates that N2.plays a dominant role in maintaining GWs at least at high latitudes of the middle *** evidence also partially explains the previous results regarding the phase changes of annual oscillations of GWs at high latitudes.

关键词： atmospheric static stability gravity waves annual oscillation semiannual oscillation mesopause

Diurnal variations of turbulence parameters over the tropical oceanic upper troposphere during SCSMEX

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science{1.(Technological sciences) 2014年第2期57卷 351-359页

作者： liu {1. {2. jiyao YUAN Wei state {1. {2. of space weather Center for Space Science and Applied ResearchChinese Academy of Sciences College of Mathematics and Information science Henan Normal University

Using the method of Thorpe analysis, the TKE （turbulence kinematic energy） dissipation rate （e） and turbulence diffusivity （K） were derived from the RS （radiosounding） measurements in the tropical oceanic upper troposphere. The measurements were performed four times per day during two intense observation periods （May 5-2., and June 5-2.） on the Kexue #1.scientific observation ship of SCSMEX （South{1. Sea Monsoon EXperiment） in 1.98. There are three new features obtained from our analysis. First, the responses of e and K to the onset of monsoon are negligible over the ocean at least for the data used here Second, the temporal variations of e and K are in a similar manner and exhibit strong diurnal variations. The diurnal variations achieve their maxima in the morning （08 LT） and early afternoon （1. LT）, and achieve their minima in the evening （2. LT） and early morning hours （02.LT）. The diurnal variations of turbulence parameters （e and K） and their responses to the onset of monsoon are entirely different from those derived over land at similar latitudes. Finally, although the correlations between the variations of e and MCSs （mesoscale convective systems）, which were derived from TRMM （tropical rainfall measuring mis- sion） satellite, are not very well in only few days, the diurnal variations of e averaged over May and June are strongly correlat- ed with the diurnal variations of MCSs with correlation factors of 0.79 and 0.94, respectively. This indicates that the turbulence and its diurnal variations over the tropic oceanic upper stratosphere region are highly related to the MCSs.

关键词： diurnal variation turbulence tropical troposphere mesoscale convection systems

Nonlinear interactions between gravity waves and tides

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science{1. Earth sciences 2007年第8期50卷 1273-1279页

作者： liu {1. {2. jiyao MA RuiPing state {1. {2. of space weather Center for Space Science and Applied researchChinese Academy of SciencesBeijing 100080China Graduate University of Chinese Academy of sciences Beijing 100049China

In this study, we present the nonlinear interactions between gravity waves (GWs) and tides by using the 2. numerical model for the nonlinear propagation of GWs in the compressible atmosphere. During the propagation in the tidal background, GWs become instable in three regions, that is z = 75―85 km, z = 90―1.0 km and z = 1.5―1.0 km. The vertical wavelength firstly varies gradually from the initial 1. km to 2. km. Then the newly generated longer waves are gradually compressed. The longer and shorter waves occur in the regions where GWs propagate in the reverse and the same direction of the hori-zontal mean wind respectively. In addition, GWs can propagate above the main breaking region (90—1.0 km). During GWs propagation, not only the mean wind is accelerated, but also the amplitude of tide is amplified. Especially, after GWs become instable, this amplified effect to the tidal amplitude is much obvious.

关键词： gravity waves tides mean wind nonlinear interactions gravity waves parameterization

Influences of non-isothermal atmospheric backgrounds on variations of gravity wave parameters

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science{1.(Technological sciences) 2012年第5期55卷 1251-1257页

作者： liu {1. ZHOU QiHou YUAN Wei {2. jiyao state {1. {2. of space weather Center for Space Science and Applied ResearchChinese Academy of Sciences Beijing 100190China College of Mathematics and Information science Henan Normal UniversityXinxiang 453007China School of Electrical Engineering Zhengzhou UniversityZhengzhou 450001China Electrical and Computer Engineering Department Miami UniversityOxfordOhioUSA

Because of the importance of gravity waves （GWs） in coupling different atmospheric regions, further studies are necessary to investigate the characteristics of GW propagation in a non-isothermal atmosphere. Using a nonlinear numerical model, we simulate the propagation of small amplitude GWs with various wavelengths in different non-isothermal atmospheres. Our re- sults show that the GW vertical wavelength undergoes sharp changes above the stratopause and mesopause region. Specifically for a GW with an initial vertical wavelength of 5 km, the seasonal background temperature structure difference at 50° latitude can cause the vertical wavelength to vary by -2.krn in the mesosphere and by as large as -4.5 km in the lower thermosphere. In addition, the GW paths exhibit great divergence in the height range of -65-1.0 kin. Our results also show that the variations of GW path, vertical wavelength and horizontal phase velocity are not synchronized in a non-isothermal atmosphere as in an isothermal atmosphere. Despite the fact that all GWs change their characteristics as they propagate upward in a non-isothermal atmosphere, the variations relative to the initial parameters at a reference height are similar for different initial vertical wavelengths. Our results indicate that the changing characteristics of a gravity wave in a non-isothermal atmosphere need to be considered when investigating the relationship of GWs at two different heights.

关键词： gravity wave non-isothermal atmosphere atmospheric coupling

First experiment of spectrometric observation of hydroxyl emission and rotational temperature in the mesopause in china

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science{1.(Technological sciences) 2012年第5期55卷 1312-1318页

作者： ZHU YaJun xu {1. YUAN Wei {2. xiao state {1. {2. of space weather Center for Space Science and Applied ResearchChinese Academy of SciencesBeijing 100190China Graduate University of Chinese Academy of sciences Beijing 100049China

A SpectroMeter of Atmospheric RadiaTion （SMART） was developed and installed at the Xinglong station of the National Astronomical Observatories in Hebei province, china, which was supported by the Meridian Project [1.. The experimental tests of spectrometric observation of the hydroxyl emission and rotational temperature in china were conducted for the first time on the night of February 2., 2.1. and the night of April 2., 2.1., respectively. OH 6-2.band and OH 8-3 band spectra were measured and the rotational temperature was retrieved. Hourly average temperatures （1.6.82.6.40） K of OH 8-3 band and （1.8.07±6.73） K of OH 6-2.band were derived from the spectra observed on the night of February 2.,2.1.. Intensities and ro- tational temperature against local time were determined by the spectra measured in the whole night of April 2., 2.1.. The rotational temperature was consistent with the spatial average temperature of NRLMSISE00 empirical model at height 83-91.km and the average temperature of TIMED/SABER from April to May of seven years at height 83-91.kin, with some discrepancies. The results showed that the new instrument and the retrieval method of the rotational temperature can give reasonable results of the airglow emission of OH and the temperature of mesopause.

关键词： SMART spectrometer OH airglow rotational temperature mesopause

Joint observation of the concentric gravity wave event on the Tibetan Plateau

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Earth and Planetary Physics 2022年第3期6卷 219-227页

作者： Chang Lai PengWei Li jiyao {1. Wei Yuan Jia Yue {2. liu Kogure Masaru LiLi Qian School of science Chongqing University of Posts and TelecommunicationsChongqing 400065China state {1. {2. of space weather Center for Space Science and Applied ResearchChinese Academy of SciencesBeijing 110000China Department of Physics Catholic University of AmericaWashingtonDC 20064USA College of Mathematics and Information science Henan Normal UniversityXinxiang 410700China Department of Earth and Planetary science Kyushu UniversityFukuoka 8190395Japan

A concentric gravity wave event was captured by a photographer in NagarzêCounty(90.2.°N,2..33°E)between 02.00 and 04:00(local time)on May 1.,*** concentric gravity wave event was also observed by the Suomi National Polar-orbiting Partnership satellite and the all-sky airglow imager at Yangbajing station(90.5°E,30.1.N).The temporal and spatial information on gravity waves from the photographs provided a rare opportunity to study the propagation of gravity waves over the Tibetan *** to wind and temperature data from the MERRA-2.reanalysis(Modern-Era Retrospective analysis for {2. and Applications,Version 2.and empirical models(NRLMSISE-00[Naval {2. laboratory Mass Spectrometer and Incoherent Scatter Radar Exosphere]and HWM[horizontal wind model]),we inversely derived the propagation trajectory from the observed wave pattern to the source region by using the ray-tracing *** source of the concentric gravity wave was identified as deep convection in Bangladesh(90.6°E,2..0°N).The maximum background wind speed in the propagation direction(31.05 m/s)was less than the phase speed of 53 m/s,which is consistent with the wind-filtering theory.

关键词： concentric gravity wave ray-tracing method convection source Tibetan Plateau

The Lyman-alpha Solar Telescope(LST) for the ASO-S mission——Ⅱ. design of LST

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research in Astronomy and Astrophysics 2019年第11期19卷 33-48页

作者： Bo Chen Hui Li Ke-Fei Song Quan-Feng Guo Pei-Jie Zhang Ling-Ping He Shuang Dai xiao-Dong Wang Hai-Feng Wang Chun-Long {1. Hong-Ji Zhang Guang Zhang Yunqi Wang Shi-Jie {1. Hong-Xin Zhang Lei {1. Shi-Lei Mao Yang {1. Jia-Hao Peng Peng Wang Liang Sun Yang {1. Zhen-Wei Han Yan-Long Wang Kun Wu Guang-Xing Ding Peng Zhou Xin Zheng Ming-Yi Xia Qing-Wen Wu Jin-Jiang Xie Ya Chen Shu-Mei Song Hong Wang Bo Zhu Chang-Bo Chu Wen-Gang Yang Li Feng Yu Huang Wei-Qun Gan Ying Li Jing-Wei Li Lei Lu Jian-Chao xue Bei-Li Ying Ming-Zhe Sun Cheng Zhu Wei-Min Bao Lei Deng Zeng-Shan Yin Changchun Institute of Optics FineMechanics and PhysicsChinese Academy of SciencesChangchun 130033China state {1. {2. of applied Optics Changchun 130033China key {1. of Dark Matter and {2. Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210034China School of Astronomy and space {1. University of Science and Technology of ChinaHefei 230026China Xi’an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi’an 710119China Shandong University Weihai 264209China Innovation Academy for Microsatellites Chinese Academy of SciencesShanghai 201210China

As one of the three payloads for the Advanced space-based Solar Observatory(ASO-S)mission,the Lyman-alpha(Lyα)Solar Telescope(LST)is composed of three instruments:a Solar Corona Imager(SCI),a LyαSolar Disk Imager(SDI)and a full-disk White-light Solar Telescope(WST).When working in-orbit,LST will simultaneously perform high-resolution imaging observations of all regions from the solar disk to the inner corona up to 2.5 R⊙(R⊙stands for the mean solar radius)with a spatial resolution of 4.8′′and {1.′′for coronal and disk observations,respectively,and a temporal resolution of 30–1.0 s and 1.12. s for coronal and disk observations,*** maximum exposure time can be up to2. s due to precise pointing and image stabilization *** the three telescopes of LST,SCI is a dual-waveband coronagraph simultaneously and independently observing the inner corona in the HI Lyα(1.1.6±1. nm)line and white light(WL)(700±40 nm)wavebands by using a narrowband Lyαbeam splitter and has a field of view(FOV)from 1.1 to 2.5 R⊙.The stray-light suppression level can attain1.^-6 B⊙(B⊙is the mean brightness of the solar disk)at 1.1 R⊙and≤5×1.^-8 B⊙at 2.5 R⊙.SDI and WST are solar disk imagers working in the Lyαline and 360.0 nm wavebands,respectively,which adopt an off-axis two-mirror reflective structure with an FOV up to {1. R⊙,covering the inner coronal edge area and relating to coronal *** present the up-to-date design for the LST payload.

关键词： telescopes—instrumentation high angular resolution—Sun flares—Sun coronal mass ejections(CMEs)—Sun UV radiation