[G06-4] Ionosphere and space weather II

[G06-4-01] S4 index observations and global morphology of ionospheric scintillations using FS3/COSMIC GPS radio occultation data

^○Lung-Chih Tsai¹, Shin-Yi Su¹, Chao-Han Liu^1,2 (1.National Central University, Taoyuan, Taiwan, 2.Academia Sinica, Taipei, Taiwan)

We report on the FormoSat-3/ Constellation Observing System for Meteorology, Ionosphere and Climate (FS3/COSMIC) limb-viewing observations of GPS L-band scintillations since mid-2006 and propose to study global F-layer irregularity morphology. The FS3/COSMIC has generally performed >1000 ionospheric radio occultation (RO) observations per day. We reprocess 1-Hz amplitude data and obtain complete limb-viewing profiles of the undersampling-S4 scintillation index from about 80% of the RO observations. There are a few percent of FS3/COSMIC RO observations having >0.09 undersampling S4max values on average. However, seven identified areas Central Pacific Area (-20~20 deg dip latitude, 160 deg E~130 deg W), South American Area (-20~20 deg dip latitude, 100 deg W~30 deg W), African Area (-20~20 deg dip latitude, 30 deg W~50 deg E), European Area (30~55 deg N, 0~55 deg E), Japan Sea Area (35~55 deg N, 120~150 deg E), Arctic Area (>65 deg dip latitude) and Antarctic Area (<-65 deg dip latitude) have been designated to have a much higher percentage of strong limb-viewing L-band scintillations. During these years in most of the last sunspot cycle from mid-2006 to the end 2014, the scintillation climatology, namely, its variations with each identified area, season, local time, magnetic activity and solar activity have been documented.