TY  - JOUR
A1  - Sobhkhiz-Miandehi, Sahar
A1  - Yamazaki, Yosuke
A1  - Arras, Christina
A1  - Miyoshi, Yasunobu
A1  - Shinagawa, Hiroyuki
T1  - Comparison of the tidal signatures in sporadic E and vertical ion convergence rate, using FORMOSAT-3/COSMIC radio occultation observations and GAIA model
JF  - Earth, planets and space : EPS
N2  - Sporadic E or Es is a transient phenomenon where thin layers of enhanced electron density appear in the ionospheric E region (90-120 km altitude). The neutral wind shear caused by atmospheric tides can lead ions to converge vertically at E-region heights and form the Es layer. This research aims to determine the role of atmospheric solar and lunar tides in Es occurrence. For this purpose, radio occultation data of FORMOSAT-3/COSMIC have been used, which provide complete global coverage of Es events. Moreover, GAIA model simulations have been employed to evaluate the vertical ion convergence induced by solar tides. The results show both migrating and non-migrating solar tidal signatures and the semidiurnal migrating lunar tidal signature mainly in low and mid-latitude Es occurrence. The seasonal variation of the migrating solar tidal components of Es is in good agreement with those in the vertical ion convergence derived from GAIA at higher altitudes. Furthermore, some non-migrating components of solar tides, including semidiurnal westward wavenumbers 1 and 3 and diurnal eastward wavenumbers 2 and 3, also significantly affect the Es occurrence rate.
KW  - Sporadic E
KW  - Es
KW  - wind shear
KW  - solar tide
KW  - lunar tide
KW  - GAIA
KW  - radio occultation
Y1  - 2022
U6  - https://doi.org/10.1186/s40623-022-01637-y
SN  - 1880-5981
VL  - 74
IS  - 1
PB  - Springer
CY  - Heidelberg
ER  -