A Study on the Quarterdiurnal Tide in the Thermosphere at Arecibo During the February 2016 Sudden Stratospheric Warming Event

Geophysical Research Letters RESEARCH LETTER 10.1029/2018GL080422 Key Points: • A strong quarterdiurnal tide is first observed at the F region in the low latitudes • The enhancement of the QDT is most likely due to the effect of the 2016 SSW • The nonlinear interaction between DT and TDT is important in amplifying the QDT during the 2016 SSW A Study on the Quarterdiurnal Tide in the Thermosphere at Arecibo During the February 2016 Sudden Stratospheric Warming Event Yun Gong1,2 , Zheng Ma1,2 , Xiedong Lv1,2, Shaodong Zhang1,2,3 Nestor Aponte5, and Michael Sulzer5 , Qihou Zhou4 , 1 School of Electronic Information, Wuhan University, Wuhan, China, 2Key Laboratory of Geospace Environment and Geodesy, Ministry of Education, Wuhan, China, 3State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, Wuhan, China, 4Electrical and Computer Engineering Department, Miami University, Oxford, OH, USA, 5Arecibo Observatory, Arecibo, Puerto Rico Abstract Using data collected from the Arecibo incoherent scatter radar during 5–10 February 2016, we Correspondence to: Y. Gong and S. Zhang, yun.gong@whu.edu.cn; zsd@whu.edu.cn Citation: Gong, Y., Ma, Z., Lv, X., Zhang, S., Zhou, Q., Aponte, N., & Sulzer, M. (2018). A study on the quarterdiurnal tide in the thermosphere at Arecibo during the February 2016 sudden stratospheric warming event. Geophysical Research Letters, 45, 13,142–13,149. https://doi. org/10.1029/2018GL080422 Received 25 SEP 2018 Accepted 25 NOV 2018 Accepted article online 28 NOV 2018 Published online 10 DEC 2018 present a study on the quarterdiurnal tide (QDT) from 250 to 360 km. A sudden stratospheric warming (SSW) event occurred on 8 February coincided with our observation. The maximum amplitude of the QDT, at ~37 m/s, is comparable with the diurnal tide and much larger than the semidiurnal tide. The QDT is largely evanescent. Our results manifest that the F region QDT could be as important as the diurnal and semidiurnal tides. The tidal waves show large variability before and after the commencement of the SSW. Our analysis indicates that the enhancement of the QDT is most likely due to the effect of the SSW. Nonlinear interaction of the diurnal tide with the terdiurnal tide is found to play a significant role in amplifying the QDT during the SSW event. Plain Language Summary We report the first observation and analysis of a strong quarterdiurnal tide in the thermosphere at low latitudes, based on data collected from dual-beam incoherent scatter radar at Arecibo Observatory. Our study reveals that the quarterdiurnal tide in the thermosphere is just as important as the commonly studied diurnal and semidiurnal tides. According to our analysis, the enhancement of the quarterdiurnal tide in the thermosphere is associated with a sudden stratospheric warming event for the first time. Nonlinear interaction between diurnal and terdiurnal tides is important in enhancing the quarterdiurnal tide. We show that the quarterdiurnal tide is a major contributor to the thermospheric dynamics. The reported results will help modelers to include quarterdiurnal tides into their models to better describe thermospheric dynamics. 1. Introduction ©2018. American Geophysical Union. All Rights Reserved. GONG ET AL. Solar tides are large-scale atmospheric motions generated by the periodic heating of the Sun. Due to this heating manner, periods of the tidal waves are related to the Earth’s rotation period and its harmonics. Tidal waves with periods of 24, 12, and 8 hr are often observed to have a large amplitude. They have been studied extensively because of their significant impacts on the transportation of the atmospheric energy (e.g., Forbes, 1995; Oberheide et al., 2009, 2011; Yiğit & Medvedev, 2015). In recent years, the quarterdiurnal tide (QDT) has received more and more attention (Jacobi et al., 2017, and references therein). She et al. (2002) observed the 6-hr tide in the mesopause based on lidar temperature measurement over Fort Collins (41°N, 105°W). Their results showed the QTD having a small amplitude and unorganized phase. Through highlatitude radar observations at Esrange (68°N, 21°E) and model simulations, Smith et al. (2004) reported that the largest amplitude of QDT in the mesosphere and lower thermosphere (MLT) region occurred during winter. Based on the long-term meteor radar observations over Collm (51°N, 13°E) and Obninsk (55°N, 37°E), Jacobi et al. (2017) reported that the amplitudes of QDT increase with height and the QDT has long vertical wavelengths and strong amplitudes during winter. Aside from the ground-based measurements, strong QDT during winter has been captured by satellite observations (Liu et al., 2015; Xu et al., 2012, 2014). Using the global temperature measurement from the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument, Xu et al. (2014) suggested that nonmigrating 6-hr tides in the stratosphere and mesosphere are mainly generated by interactions between diurnal (DT) and terdiurnal tides (TDT). Based on the SABER temperature data, Liu et al. (2015) stated that the generation of the migrating 6-hr 13,142 Geophysical Research Letters 10.1029/2018GL080422 tides could be due to ozone heating in the stratosphere. Although there are many reports on QDT, most of the studies are restricted to below 120 km due to instrument limitation. In the thermosphere, the tidal wave is important because it plays an important role in seeding ionospheric instabilities and bubbles (e.g., Fritts et al., 2008; Gong et al., 2012). Oberheide et al. (2011) stated that a lack of tidal observations from 120 to 400 km is a major challenge in understanding the ionospherethermosphere system. Short period tides appear to be particularly important in generating ionospheric variability, such as midnight collapse (Gong et al., 2012). Above 120 km, incoherent scatter radar (ISR) is ideal for studying the variation of the neutral wind with good temporal and spatial resolutions. However, it appears that only one study on QDT have been published using such a technique (Gong et al., 2013). Although Gong et al. (2013) presented the vertical structure of a QDT in the F region, the QDT amplitude is very weak and the focus is on the discussion of the much stronger diurnal and semidiurnal tides (SDT). Figure 1. Temporal variation of neutral temperature, zonal wind, Kp, and F10.7 in 2016 from 20 January to 29 February. (a) Temperature at 90°N at 10 hPa, (b) zonally mean zonal winds averaged in a latitude range from 80 to 90°N at 10 hPa, (c) zonally mean zonal wind at 60°N at 10 hPa, (d) Kp indices, and (e) F10.7 index. Sudden stratospheric warming (SSW) is a large-scale atmospheric event occurring in the polar middle atmosphere during winter. During an SSW, the stratospheric temperature increases tens of degrees within several days (Matsuno, 1971). There are ample evidence that this polar event can result in strong perturbations in the atmosphere and ionosphere (e.g., Chau et al., 2012; Fejer et al., 2011; Gong et al., 2016, 2018; Liu et al., 2010; Ma et al., 2017; Manney et al., 2009; Pedatella & Forbes, 2010). In this paper, we focus on the study of a QDT and our observation coincides with an SSW event. The QDT is extracted from the Arecibo dual-beam ISR measurements in the thermospheric meridional wind. In the following, the Arecibo ISR operation mode and the data processing method are presented in section 2. The results and discussions are given in section 3. The conclusions are summarized in section 4. 2. Data Analysis The dual-beam ISR experiment was conducted from 11:55 LT 5 February to 12:00 LT 10 February 2016, at the Arecibo Observatory, Puerto Rico (18.3°N, 66.7°W). Throughout the observation, one beam pointed vertically, while the other beam rotated at a 75° elevation angle. The experiment made use of the coded long-pulse technique developed by Sulzer (1986). Nonlinear fitting to the ISR ion line spectrum yields the following parameters for our present study: electron density, ion and electron temperature, and line-of-sight velocity. Zhou and Sulzer (1997) give a detailed description of the derivation of these parameters. The vector ion drifts are obtained from the line-of-sight drifts using the linear regularization technique discussed by Sulzer et al. (2005). Neutral wind is further deduced from the vector ion drifts and other ISR measurements (e.g., Gong et al., 2013). The zonal wind depends strongly on the ratio of ion-neutral collision frequency to the ion gyrofrequency (ρ) and the electric field. In the F region, since the ion-neutral collision frequency is much smaller than the ion gyrofrequency, the value of ρ is very small. Hence, the zonal wind in the thermosphere is not reliable because it is proportional to ρ and any error in estimating the zonal wind will be amplified dramatically by a factor of 1/ρ (Gong et al., 2013). Therefore, only the meridional wind is used in this study. Many studies have presented detail derivations of the thermospheric meridional wind using the ISR techniques (e.g., Aponte et al., 2005; Buonsanto & Witasse, 1999; Gong & Zhou, 2011). The uncertainty of the meridional wind is largely due to O+-O collision frequency, which is adopted from Pesnell et al. (1993). Given a 20% uncertainty in the O+-O collision frequency, the measurement error of the thermospheric meridional wind at 300 km is estimated as ~10 m/s. A more detailed analysis of the measurement error using ISR techniques can be found in Buonsanto and Witasse (1999). The stratospheric and geophysical conditions in 2016 from 20 January to 29 February are presented in Figure 1. The stratospheric temperature and zonal wind data are obtained from the Goddard Space Flight Center, National Aeronautics and Space Administration (NASA), website http://acdb-ext.gsfc. nasa.gov/Data_services/met/ann_data.html. The Kp and F10.7 indexes are obtained from the website GONG ET AL. 13,143 Geophysical Research Letters Figure 2. Normalized Lomb-Scargle periodogram of the meridional wind in the period of 06:00 LT 7 February to 12:00 LT 8 February 2016. The vertical resolution is 6 km. 10.1029/2018GL080422 https://omniweb.gsfc.nasa.gov/form/dx1.html. As shown in Figure 1, the temperature at 90°N reached its maximum on 9 February (day 40). If the difference of the zonal-mean temperature between 90 and 60°N at 10 hPa is positive and persists for more than 5 days, the World Meteorological Organization defines it as an SSW event. The temperature at 90°N increased ~54.7°K from day 37 to 40 during the period of our interest. Although the zonal-mean zonal wind at 60°N and 10 hPa dramatically reduced from ~40 m/s on 5 February to ~12 m/s on 9 February, its direction remained constant. Hence, this event is classified as a minor SSW. Manney et al. (2015) reported that a minor SSW could also have a great impact on polar processes. As shown in Figure 1b, the circumpolar westward wind appears on day 39 (8 February) in 2016, which is defined as the SSW onset date. According to Figures 1d and 1e, the geomagnetic activities are low (Kp index is less than 3) and solar activities are moderate (F10.7 is smaller than 120 solar flux unit [SFU = 10 22 W/m2/Hz]) during the SSW event. In order to derive the dominant oscillation modes in the meridional wind, the Lomb-Scargle (LS) method (Press et al., 1992) is used to obtain the normalized periodogram. Figure 2 presents the results of the LS periodogram in the period from 06:00 LT 7 February to 12:00 LT 8 February 2016. An LS value of 0.13 corresponds to a confidence level of 95%. As seen from Figure 2, the QDT is comparable with the DT at around 300 km and much stronger than the SDT. To our knowledge, this is the first time that such a strong 6-hr oscillation has been observed in the thermosphere in low latitudes. In order to investigate the temporal variations of the QDT, a 24-hr sliding window with a step of 6 hr is used to perform least squares fittings in the meridional wind. In each window, we simultaneously extract the amplitudes and phases of DT, SDT, TDT, QDT, and daily background wind from the meridional wind, which are presented in the following. 3. Results and Discussions The fitted amplitudes and phases of the DT (orange), SDT (green), TDT (blue), QDT (red), and the daily mean meridional wind (purple) in the F region are presented in Figure 3. The top two panels of Figure 3 are the temporal variations of the tidal phases (a) and the amplitudes of the tides and mean meridional wind (b). The results in Figures 3a and 3b are obtained by averaging the fitting results in the altitude range from 276 to 360 km. The bottom panels display the altitudinal variations of tidal amplitudes (c) and phases (d), which are derived by averaging the fitting results in the period from 78 to 96-hr shown in Figures 3a and 3b. The error bars in Figure 3 represent the standard deviations. Note that in this study, the time in Figure 3b is defined as the end of the sliding window used for the fitting. The 6-hr oscillation reaches its maximum amplitude of ~37 m/s at 78-hr as seen in Figure 3b. This value is obtained by using a fitting window from 54 to 78-hr. As shown in Figures 3a and 3b, the QDT amplitude is less than 10 m/s and its phase shows large temporal fluctuation before 48 hr, which indicates a lack of the QDT. From then on until 72 hr, the QDT amplitude slowly increases and its phase shows less variations. In the time interval from 78 to 96 hr, the QDT amplitude quickly increases to ~37 m/s that is almost 2 times larger than that before 72 hr. It should be noted that a 6-hr oscillation may be a gravity wave, tide, or a combination of tidal and gravity waves. The most significant difference between tidal and gravity waves is that the phase of a tidal wave is coherent, while the phase of a gravity wave is largely irregular. As seen in Figure 3a, the phase of the 6-hr oscillation in the period from 78 to 96 hr is very consistent, which indicates that this oscillation is a tidal wave. During this period, the QDT amplitude is comparable to that of the DT and much larger than the amplitudes of the SDT and TDT. After 96 hr, the QDT amplitude rapidly decreases and its phase starts to fluctuate. The amplitude and phase results of the QDT as a function of altitude are shown in Figures 3c and 3d, respectively. The QDT amplitude quickly increases from ~10 to ~35 m/s from 264 to 288 km, and then largely remains constant at 35 m/s from 288 to 360 km. Above 276 km, the QDT amplitude is much stronger than the SDT amplitude. From 288 to 300 km, the QDT amplitude is as large as the DT amplitude. The lack of QDT phase variation indicates that the QDT is evanescent. Using a comprehensive numerical model, Forbes (1982a, 1982b) reported that the amplitudes and phases of DT and SDT tend to constant values above ~200 km. Our results are largely GONG ET AL. 13,144 Geophysical Research Letters 10.1029/2018GL080422 consistent with these numerical studies except that the DT amplitude increases with height. However, no numerical studies on the F region QDT have been reported. Harper (1981) presented an analysis of DT and SDT in the F region using the Arecibo ISR measurements. He stated that the SDT dominates the F region during nonwinter conditions. However, he did not discuss the vertical structure of the F region tidal waves in winter condition. Based on the Arecibo ISR measurements in January 2010, Gong and Zhou (2011) and Gong et al. (2013) revealed the vertical structure of DT, SDT, TDT, and QDT in the F region. Our present observations are consistent with previous Arecibo results in that the DT is the dominant tidal component in the F region during winter, and the phases of the DT and SDT in the F region are largely constant. Although Gong et al. (2013) reported the vertical variation of a QDT in the F region, they found that the QDT amplitude is less than 10 m/s at the altitudes of interest here and it is much weaker than the DT amplitude. Our present results indicate that the F region QDT in the low latitudes could be as strong as the commonly recognized diurnal and semidiurnal tides. As mentioned in section 2, the SSW event occurred on 8 February 2016 coincides with our observation. The dashed black lines shown in Figures 3a and 3b indicate the starting time of the SSW. Many studies have reported that variations of thermospheric tides are associated with SSW events (e.g., Chau et al., 2012; Goncharenko et al., 2013; Gong et al., 2013; Jin et al., 2012; Pedatella et al., 2016; Sridharan, 2017; Wu et al., 2016). The migrating semidiurnal solar (SW2) and lunar (M2) tides, and the westward propagating nonmigrating SDT with a zonal wavenumber of one (SW1), are reported to be enhanced during SSWs (Pedatella et al., 2016, and reference therein). An enhancement of the semidiurnal pattern in vertical drifts, total electron content, electron density, and ion temperature are observed during SSW events, which are thought to be due to the amplification of solar or lunar SDT (e.g., Chau et al., 2009, 2010; Goncharenko et al., 2013; Pancheva & Mukhtarov, 2011; Pedatella et al., 2014). Wu and Nozawa (2015) found that the 6-hr tide is enhanced during the 2010 SSW using two ground-based Fabry-Perot interferometers (FPIs) at Boulder (40°N, 105°W) and Resolute (75°N, 95°W). They suggested that the enhancement of the F region QDT might be due to the interaction between enhanced SDT and gravity waves in the lower thermosphere. Figure 3. (a) Phase and (b) amplitude variations of diurnal (orange), semiMedvedeva and Ratovsky (2017) reported that the diurnal, semidiurnal, diurnal (green), terdiurnal (blue) and quarterdiurnal (red) tides, and daily mean wind (purple) in the meridional wind as a function of time. The results and terdiurnal components in the MLT region are enhanced during the are averaged in the altitude range from 276 to 360 km. (c) Amplitude and 2016 SSW. Based on numerical experiments using thermosphere-iono(d) phase of diurnal (orange), semidiurnal (green), terdiurnal (blue), and sphere-mesosphere electrodynamics general circulation model, Liu et al. quarterdiurnal (red) tides in the meridional wind as a function of height. The results are averaged in the period from 78 to 96 hr. The error bars represent (2010) reported that nonlinear interactions between quasi-stationary plastandard deviations. The dashed line at 72 hr (00:00 LT 8 February) demarks netary waves and tides during SSWs result in a significant changes in tides the commencement of sudden stratospheric warming. globally. The tidal changes are the most prominent in the low latitudes, which leads to the thermospheric and the ionospheric disturbances. A recent review by Chau et al. (2012) provided a detailed discussion of the ionospheric and the thermospheric perturbations associated with SSWs in the equatorial and low latitude. In this study, as shown in Figure 3b, the tidal variabilities are quite different before and after the commencement of the SSW. The amplitudes of the DT, TDT, and QDT during the SSW are 2 times larger than before the SSW. The SDT amplitude quickly decreased when the SSW just occurred. After 96 hr, the SDT amplitude quickly increased from ~5 to ~30 m/s. As seen from Figure 1, the geomagnetic activities are low and solar activities are moderate during the SSW event. The geomagnetic and solar activities appear to have limited impact on the large tidal variabilities in our observation. Therefore, the enhancement of the DT, TDT, and GONG ET AL. 13,145 Geophysical Research Letters 10.1029/2018GL080422 Figure 4. (a) Bispectrum and (b) bicoherence spectrum of meridional wind at 303 km in during 00:00 LT 7 February to 06:00 LT 9 February 2016. QDT and the reduction of the SDT are very likely associated with the 2016 SSW. However, using data obtained from the Arecibo ISR in January 2010 that coincides with an SSW, Gong et al. (2013) presented an analysis of tidal waves responses to the 2010 SSW. They found that the thermospheric QDT almost disappears during the SSW although the QDT is weak before the commencement of the SSW event. It is clearly that SSWs affect the thermospheric tides in very different ways. In order to better understand the relation between the thermospheric tides and SSWs, more data need to be analyzed. The enhancement of the SDT is often observed during SSWs (e.g., Pedatella et al., 2016, and references therein), which is not consistent with our observation. As shown in Figure 3b, a decrease of the SDT amplitude occurred when the SSW just commenced. However, the SDT amplitude rapidly increased ~30 hr after the occurrence of the SSW. Sridharan et al. (2012) reported a quick decrease of a SDT over Tirunelveli (8.7°N, 77.8°E) before the commencement of the 2011 SSW and the SDT amplitude drops to 2 m/s at the SSW onset. Using the Resolute FPI measurements, Wu and Nozawa (2015) observed that the SDT amplitude decreased from ~35 to ~10 m/s from the day before the SSW occurred to the day after. Numerical simulations made by Fuller-Rowell et al. (2011) and Wang et al. (2011) predicted the reduction of the SDT amplitude and the enhancement of the TDT amplitude during SSWs. The effect of SSW on the SDT is not uniform. In order to better understand the relation between thermospheric SDT and SSWs, comprehensively observational and numerical analyses are needed. As seen from Figure 3b, after the commencement of the SSW, the QDT amplitude is well correlated with the amplitudes of the DT and TDT in the time interval from 72 to 102 hr. During the same time interval, the amplitudes of the QDT and SDT are highly anticorrelated with a correlation coefficient of 0.95, and the QDT and the mean meridional wind are perfectly correlated with a correlation coefficient of 0.98. It is possible that the SDT as a primary wave passes its energy to a secondary wave (QDT) and the mean meridional wind (zero frequency) via self-nonlinear interaction. Bispectral analysis provides an ideal tool to examine the three-wave nonlinear interaction because the phase information of the spectra could be revealed. (Huang et al., 2012; Huang et al., 2013; Kim & Powers, 1979; Xu et al., 2014). A large magnitude of the bispectrum indicates strong quadratic phase coupling caused by wave-wave interaction. The level of coherence among the three interacting waves can be examined by the bicoherence analysis (Beard et al., 1999; Kim & Powers, 1979). When the result of the bicoherence is close to unity, it indicates that a secondary wave is generated via nonlinear interaction between two primary waves. In this study, bispectral and bicoherence analysis is applied to investigate the nonlinear interactions among tidal components. According to Figure 3c, the QDT is not only strong around 306 km but has small temporal variation. The meridional wind at 306 km in the time interval from 00:00 LT 7 February to 06:00 LT 9 February 2016 are used to perform the analysis. The 54-hr data are divided into 37 segments by a 36-hr sliding window with a step of 0.5 hr. The bispectrum and bicoherence in each segment are first calculated. Then the results are averaged across all segments in order to limit the contribution of spontaneously excited tidal modes (Huang et al., 2013). The results of bispectrum and bicoherence are shown in Figures 4a and 4b. The bispectrum results are normalized to have a range between 0 and 1. In this study, we use (Ti, Tj) to denote the periods of the two primary waves of the interacting wave triad. A secondary wave would be excited via nonlinear interaction with the frequency of 1/Ti + 1/Tj (sum GONG ET AL. 13,146 Geophysical Research Letters 10.1029/2018GL080422 frequency) or |1/Ti 1/Tj| (difference frequency). As mentioned before, a QDT can be generated via nonlinear interactions of (24, 8) or (12, 12). As seen from Figure 4a, the bispectrum is strong at around (24, 8) and (24, 6), which indicates that nonlinear interactions between the DT and the TDT, and between the DT and the QDT are important. Hence, the self-nonlinear interaction of the SDT is not responsible for generating the QDT. As shown in Figure 4b and consistent with the bispectral results, the result of bicoherence is strong at around (24, 8) and (24, 6). Our results indicate that the nonlinear interaction between the DT and the TDT plays a significant role in enhancing the QDT. In addition, a secondary TDT may be generated via the nonlinear interaction between the DT and the QDT. Xu et al. (2014) revealed that nonmigrating 6-hr tides are generated by nonlinear interactions between DT and TDT, based on SABER temperature data. Also using the SABER temperature data, Liu et al. (2015) reported that the migrating 6-hr tide may be generated by the second harmonics of the migrating SDT in the low thermosphere and the nonlinear interaction between migrating diurnal and TDTs in the stratopause. Our observations show that the enhancement of the DT, TDT, and QDT is associated with the 2016 SSW. Note that our study is based on a single radar station so that all the tidal waves reported here are the combination of nonmigrating and migrating components. During the SSW, the nonlinear interaction between the DT and the TDT is strong. It may be possible that the SSW amplifies the DT and the TDT, which then interact nonlinearly to produce the QDT. However, further numerical study is needed to make a firm conclusion. 4. Summary and Conclusion Using measurements obtained from the Arecibo facility, we have deduced the meridional wind component from 250 to 360 km in the period of 5–10 February 2016. Based on the results of LS periodogram and simultaneously fitting of the DT, SDT, TDT and QDT the strong QDT is observed. The QDT is comparable with the DT and much larger than the SDT. This appears to be the first time that such a strong QDT has been reported in low latitude thermosphere. The QDT amplitude slightly varies around 35 m/s from 288 to 360 km. The phase of the QDT is largely evanescent. Our observation overlapped with a SSW event that started on 8 February 2016. The tidal waves show large variability before and after the commencement of the SSW. During the SSW, the amplitudes of the DT, TDT, and QDT experience a twofold increase compared with those before the SSW. The SDT amplitude quickly decreased prior to the occurrence of the SSW and rapidly increased about 30 hr later. The SSW is very likely responsible for the large tidal variability. According to the results of bispectrum and bicoherence analysis, a strong nonlinear interaction between the DT and the TDT is found during the SSW. It is possible that the DT and the TDT are first enhanced due to the effect of the SSW. The two primary waves then interact nonlinearly to generate the QDT. However, further investigations with observational and numerical studies are needed in order to better understand the generation of QDT in the thermosphere and its relation with SSWs. Acknowledgments The Arecibo Observatory is operated by the University of Central Florida under a cooperative agreement with the National Science Foundation. The Arecibo data used here can be obtained from the Madrigal Database at the Arecibo Observatory through http:// www.naic.edu/madrigal/index.html/. The study is supported by the National Key Research and Development Plan (2018YFC1407305), National Natural Science Foundation of China (through grants 41574142, 41304121, and 41531070), National Science Foundation grant AGS-1744033, Natural Science Foundation grant of Hubei Province (2017CFB403), and the program of China Scholarship Council (201706275008). GONG ET AL. References Aponte, N., Nicolls, M. J., Gonza’lez, S. A., Sulzer, M. P., Kelley, M. C., Robles, E., & Tepley, C. A. (2005). Instantaneous electric field measurements and derived neutral winds at Arecibo. Geophysical Research Letters, 32, L12107. https://doi.org/10.1029/2005GL022609 Beard, A. G., Mitchell, N. J., Williams, P. J. S., & Kunitake, M. (1999). Non-linear interactions between tides and planetary waves resulting in periodic tidal variability. Journal of Atmospheric and Solar-Terrestrial Physics, 61(5), 363–376. https://doi.org/10.1016/S13646826(99)00003-6 Buonsanto, M. J., & Witasse, O. G. (1999). 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