[P-EM09] Study of coupling processes in solar-terrestrial system

[PEM09-P05] RELATIONSHIP OF F LAYER HEIGHT RISE, ESF ONSET TIME, AND AMPLITUDE OF LARGE SCALE WAVE STRUCTURE

*Dyah Rahayu Martiningrum¹、Mamoru Yamamoto²、Tatsuhiro Yokoyama³、Prayitno Abadi⁴、Pornchai Supnithi⁵、Minh Le Huy⁶ (1.Graduate School of Informatics, Kyoto University、2.Research Institute for Sustainable Humanosphere, Kyoto University、3.National Institute of Informatics and Communications Technology (NICT), Tokyo、4.Solar-Terrestrial Environment Laboratory (STEL), Nagoya University、5.Faculty of Engineering King Mongkut's Institute of Technology, Ladkrabang, Thailand、6.Institute of Geophysics Vietnamese Academy of Science and Technology, Vietnam)

キーワード：F layer height rise, Large Scale Wave Structure, onset time of Equatorial Spread F

Under favourable conditions ionospheric plasma at the bottomside of the F-region can become unstable. Plasma irregularities in several scales produced by Rayleigh-Taylor Instability mechanism. The recombination process at the E-region after sunset causing the bottom side F-region electron density gradient become steep. At the same time the eastward electric field intensified just before it reverses to the westward electric field causing the peak of the F region rise known as evening prereversal enhancement. The relationship between onset time of field aligned irregularities related to ESF observed by Equatorial Atmosphere Radar during 2010-2012 with F layer height rise observed by ionosondes near geomagnetic equator, Chumphon (10.7 N; 99.4 E; 0.86 N) and Bac Lieu (9.3 N; 105.7 E; 0.62 N) is discussed in correspondence with growth rate of Rayleigh Taylor instability development. The field aligned irregularities onset time associated with equatorial spread F observed into two different cases, first case where the EPB/ESF onset time concurrent with the peak of virtual height of F region - (h’F) time. Second case where the EPB/ESF onset time happened with delay of more than 30 minutes, with reference to the peak of virtual height of F region - (h’F) time. The possibility that the amplitude of Large Scale Wave Structure obtained from GRBR data effects the height of plasma instability development also discussed.