TY - JOUR
T1 - Variations of the meteor echo heights at Beijing and Mohe, China
AU - Liu, Libo
AU - Liu, Huixin
AU - Chen, Yiding
AU - Le, Huijun
AU - Sun, Yang Yi
AU - Ning, Baiqi
AU - Hu, Lianhuan
AU - Wan, Weixing
N1 - Funding Information:
The F10.7 index is provided by NGDC through ftp://ftp.ngdc.noaa.gov/STP/space-weather/. The CIRA86 and NRLMSISE-00 models are calculated using Aerospace Blockset toolbox of MATLAB (2016a). This research was supported by National Natural Science Foundation of China (41231065, 41321003). H.L. is supported by JSPS KAKENHI grants 15K05301, 15H02135, and 15H03733. L.L. and Y.S. thank the support by the NICT International Exchange Program. We acknowledge the use of meteor radar data from the Chinese Meridian Project and from Data Center for Geophysics, Data Sharing Infrastructure of Earth System Science. The meteor radars were operated by Beijing National Observatory of Space Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences. The data can be available from the first author.
Publisher Copyright:
©2016. American Geophysical Union. All Rights Reserved.
PY - 2017/1/1
Y1 - 2017/1/1
N2 - Detecting the changing of the upper atmosphere is an important and challenging issue. The change in the meteor peak heights observed by a meteor radar should contain information of the neutral density in the meteoroid ablation region. In this work, observations from the VHF all-sky meteor radars operated at Beijing (40.3°N, 116.2°E) and Mohe (53.5°N, 122.3°E), China, are collected to explore the temporal patterns of the meteor peak heights. The daily meteor peak height is determined through a least squares fitting of the height profile of meteor radar echoes under a normal distribution assumption. There are considerable seasonal variations in the meteor peak heights, being dominated by an annual component at Beijing and a semiannual one at Mohe. Moreover, the Ensemble Empirical Mode Decomposition (EEMD) is employed to determine the overall trends in the series of the meteor peak heights. The EEMD analysis reveals an overall decrease in the meteor peak heights at both stations, indicating the descending trend in neutral density near 90 km altitude at middle latitudes. The meteor peak heights show a rather weak solar activity effect at Beijing, which is different from the positive effects reported at some other sites.
AB - Detecting the changing of the upper atmosphere is an important and challenging issue. The change in the meteor peak heights observed by a meteor radar should contain information of the neutral density in the meteoroid ablation region. In this work, observations from the VHF all-sky meteor radars operated at Beijing (40.3°N, 116.2°E) and Mohe (53.5°N, 122.3°E), China, are collected to explore the temporal patterns of the meteor peak heights. The daily meteor peak height is determined through a least squares fitting of the height profile of meteor radar echoes under a normal distribution assumption. There are considerable seasonal variations in the meteor peak heights, being dominated by an annual component at Beijing and a semiannual one at Mohe. Moreover, the Ensemble Empirical Mode Decomposition (EEMD) is employed to determine the overall trends in the series of the meteor peak heights. The EEMD analysis reveals an overall decrease in the meteor peak heights at both stations, indicating the descending trend in neutral density near 90 km altitude at middle latitudes. The meteor peak heights show a rather weak solar activity effect at Beijing, which is different from the positive effects reported at some other sites.
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U2 - 10.1002/2016JA023448
DO - 10.1002/2016JA023448
M3 - Article
AN - SCOPUS:85010637643
SN - 2169-9380
VL - 122
SP - 1117
EP - 1127
JO - Journal of Geophysical Research: Space Physics
JF - Journal of Geophysical Research: Space Physics
IS - 1
ER -