@article{94d3c3460117426391a0e068059a8e0f,
title = "Prominent Daytime TEC Enhancements Under the Quiescent Condition of January 2017",
abstract = "It is well known that the ionospheric electron densities in the F-region usually undergo day-to-day variability with the magnitude of ~20–35%, associated with the solar as well as geomagnetic activities and the meteorological forcing from the lower atmosphere. In this study, we reported remarkable enhancements in the total electron content (TEC) from the Beidou geostationary (GEO) satellites during the quiescent geophysical condition of January 2017 prior to the arrival of the sudden stratosphere warming (SSW). The daytime TEC around the equatorial ionization anomaly region increased by 75–160% and lasted for several days. The equatorial electrojet and Sq current in the ionospheric E-region at low and middle latitudes showed the corresponding increase during the TEC enhancement interval. The possible contributions from the variations of solar EUV flux and geomagnetic activity are ruled out. Our further analysis showed that the diurnal tides in the temperature from Sounding of the Atmosphere using Broadband Emission Radiometry and the solar and lunar semidiurnal tides of neutral winds from two radars over China became strong during this period of interest. These results suggest that the lower atmospheric tidal forcing could contribute to the great and long-duration TEC enhancement in the ionosphere even though the SSW had not happened yet.",
author = "Fuqing Huang and Jiuhou Lei and Ruilong Zhang and Na Li and Shengyang Gu and You Yu and Libo Liu and Charles Owolabi and Baiqi Ning and Guozhu Li and Jiahao Zhong and Tong Dang and Dexin Ren and Wen Yi and Xiaoli Luan and Xianghui Xue and Tao Yu and Faquan Li and Xiankang Dou and Akimasa Yoshikawa",
note = "Funding Information: This work was supported by the B‐type Strategic Priority Program of the Chinese Academy of Sciences (XDB41000000), the National Natural Science Foundation of China (41831070, 41974181, and 41831071), and the Open Research Project of Large Research Infrastructures of CAS—“Study on the interaction between low/mid‐latitude atmosphere and ionosphere based on the Chinese Meridian Project.” X. Luan was supported by the National Natural Science Foundation of China (41874184 and 41674154). F. Huang was supported by China Postdoctoral Science Foundation (2019M662170), the Fundamental Research Funds for the Central Universities (WK2080000130) and the Joint Open Fund of Mengcheng National Geophysical Observatory (MENGO‐202010). J. Zhong was supported by the National Natural Science Foundation of China (41804150). R. Zhang was also supported by the National Natural Science Foundation of China (41904140), National Postdoctoral Program for Innovative Talents (BX20180301), and China Postdoctoral Science Foundation (2018M640175). Thanks to Wenbin Wang and Shunrong Zhang for their helpful discussions and referees for their useful comments, which improved the paper greatly. We acknowledge OMNIWeb ( https://omniweb.gsfc.nasa.gov/ ) for Kp, Vsw, Bz, and AE; and the MAGDAS/CPMN ( http://data.icswse.kyushu-u.ac.jp/ ), INTERMAGNET ( http://www.intermagnet.org ), JMA ( https://www.jma.go.jp/jma/indexe.html ), OHP ( http://ohpdmc.eri.u-tokyo.ac.jp ), WDC ( http://www.wdc.bgs.ac.uk/data.html ), E. Yizengaw, E. Zesta, M. B. Moldwin, and the rest of the AMBER ( http://magnetometers.bc.edu/index.php/amber2 ) and SAMBA team for the magnetometer data; Beidou GEO TEC data are provided by the University of Science and Technology of China, the Data Center for Geophysics, National Earth System Science Data Sharing Infrastructure at BNOSE, IGGCAS ( http://wdc.geophys.ac.cn/ ), and NASA CDDIS ( ftp://cddis.gsfc.nasa.gov/ ); the EUV are downloaded from dornsifecms.usc.edu/space‐sciences‐center/; the data of O/N ratio are obtained from guvitimed.jhuapl.edu/data_products_legacy. The SABER observations are available at http://saber.gats-inc.com ; the ERA data are download from https://www.esrl.noaa.gov/psd/data/gridded/tables/daily.html; and the data of Chinese Meridian Project are access from https://data.meridianproject.ac.cn/ . The calculations were completed on the supercomputing system in the Supercomputing Center of University of Science and Technology of China. 2 Funding Information: This work was supported by the B-type Strategic Priority Program of the Chinese Academy of Sciences (XDB41000000), the National Natural Science Foundation of China (41831070, 41974181, and 41831071), and the Open Research Project of Large Research Infrastructures of CAS—“Study on the interaction between low/mid-latitude atmosphere and ionosphere based on the Chinese Meridian Project.” X. Luan was supported by the National Natural Science Foundation of China (41874184 and 41674154). F. Huang was supported by China Postdoctoral Science Foundation (2019M662170), the Fundamental Research Funds for the Central Universities (WK2080000130) and the Joint Open Fund of Mengcheng National Geophysical Observatory (MENGO-202010). J. Zhong was supported by the National Natural Science Foundation of China (41804150). R. Zhang was also supported by the National Natural Science Foundation of China (41904140), National Postdoctoral Program for Innovative Talents (BX20180301), and China Postdoctoral Science Foundation (2018M640175). Thanks to Wenbin Wang and Shunrong Zhang for their helpful discussions and referees for their useful comments, which improved the paper greatly. We acknowledge OMNIWeb (https://omniweb.gsfc.nasa.gov/) for Kp, Vsw, Bz, and AE; and the MAGDAS/CPMN (http://data.icswse.kyushu-u.ac.jp/), INTERMAGNET (http://www.intermagnet.org), JMA (https://www.jma.go.jp/jma/indexe.html), OHP (http://ohpdmc.eri.u-tokyo.ac.jp), WDC (http://www.wdc.bgs.ac.uk/data.html), E. Yizengaw, E. Zesta, M. B. Moldwin, and the rest of the AMBER (http://magnetometers.bc.edu/index.php/amber2) and SAMBA team for the magnetometer data; Beidou GEO TEC data are provided by the University of Science and Technology of China, the Data Center for Geophysics, National Earth System Science Data Sharing Infrastructure at BNOSE, IGGCAS (http://wdc.geophys.ac.cn/), and NASA CDDIS (ftp://cddis.gsfc.nasa.gov/); the EUV are downloaded from dornsifecms.usc.edu/space-sciences-center/; the data of O/N2 ratio are obtained from guvitimed.jhuapl.edu/data_products_legacy. The SABER observations are available at http://saber.gats-inc.com; the ERA data are download from https://www.esrl.noaa.gov/psd/data/gridded/tables/daily.html; and the data of Chinese Meridian Project are access from https://data.meridianproject.ac.cn/. The calculations were completed on the supercomputing system in the Supercomputing Center of University of Science and Technology of China. Publisher Copyright: {\textcopyright}2020. American Geophysical Union. All Rights Reserved.",
year = "2020",
month = jul,
day = "28",
doi = "10.1029/2020GL088398",
language = "English",
volume = "47",
journal = "Geophysical Research Letters",
issn = "0094-8276",
publisher = "American Geophysical Union",
number = "14",
}