TY - JOUR
T1 - Ionospheric responses to the 21 August 2017 solar eclipse by using data assimilation approach
AU - Chen, Chia-Hung
AU - Lin, Charles
AU - Matsuo, Tomoko
N1 - Funding Information:
This paper is supported by Ministry of Science and Technology (MOST) and National Space Organization (NSPO) of Taiwan to National Cheng Kung University under MOST-107-2119-M-006-023 and NSPO-S-108002.
PY - 2019/12/1
Y1 - 2019/12/1
N2 - Using the physics-based thermosphere-ionosphere model (NCAR-TIEGCM) with an ensemble Kalman filter, this study reports the first data assimilative analysis of the ionosphere responses to the solar eclipse on 21 August 2017. The system, using a 2-min assimilation cycle of data from ground-based GNSS observations, show dynamic variations of the equatorial ionization anomaly (EIA) due to the electrodynamic effects of the solar eclipse. Two major ionospheric responses are captured: (1) an early appearance of EIA at the westward boundary of moon shadow and (2) an enhanced EIA at lower latitudes and suppressed EIA at the higher latitudes. These eclipse-induced conjugate EIA variations are produced by an eastward electric field perturbation around the magnetic equator and a westward electric field perturbation at the higher latitudes. [Figure not available: see fulltext.].
AB - Using the physics-based thermosphere-ionosphere model (NCAR-TIEGCM) with an ensemble Kalman filter, this study reports the first data assimilative analysis of the ionosphere responses to the solar eclipse on 21 August 2017. The system, using a 2-min assimilation cycle of data from ground-based GNSS observations, show dynamic variations of the equatorial ionization anomaly (EIA) due to the electrodynamic effects of the solar eclipse. Two major ionospheric responses are captured: (1) an early appearance of EIA at the westward boundary of moon shadow and (2) an enhanced EIA at lower latitudes and suppressed EIA at the higher latitudes. These eclipse-induced conjugate EIA variations are produced by an eastward electric field perturbation around the magnetic equator and a westward electric field perturbation at the higher latitudes. [Figure not available: see fulltext.].
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U2 - 10.1186/s40645-019-0263-4
DO - 10.1186/s40645-019-0263-4
M3 - Article
AN - SCOPUS:85061040832
VL - 6
JO - Progress in Earth and Planetary Science
JF - Progress in Earth and Planetary Science
SN - 2197-4284
IS - 1
M1 - 13
ER -