Learning center web of atmosphere variability, weather variability, and disaster occurrence at equatorial magnetic latitude station, Chumphon, Thailand
Abstract:
This research proposes a learning center web of atmosphere variability, weather variability, and disaster occurrence at equatorial magnetic latitude station, Chumphon, Thailand. As for the research on the second year, the variations of bottomside thickness
parameters of the ionosphere and the ionospheric storm scale based on foF2 values are studied. The bottomside thickness parameter is investigated by using the observed Digisonde data from twelve ionospheric monitoring stations in GIRO (Global Ionospheric
Radio Observatory) database. Their geographic latitudes are divided into four zones such as 0°20°, 20°-40°, 40°60°, and higher than 60°. The retrieved data are grouped into three seasons regarding to the north hemisphere, i.e., equinox, summer, and winter. The
bottomside thickness parameters of all twelve stations are computed for each zone, and then their diurnal and seasonal variations are compared with those obtained from Digisonde. The studied results show that the bottomside thickness parameters computed using the proposed equation (B2botP) have similar trends as well as nearby values with the observed ones (B0_obs). The absolute differences of all stations in summer season range from 0.09 25.11 km. Meanwhile, the absolute differences in equinox and winter seasons cover from 0.03 16.46 km and 0.02 22.49 km, respectively. The bottomside thickness parameter proposed in this research is an alternative method to compute approximately both the TEC and the GPS propagation delay for GNSS receiver positioning and disaster prediction. Refer to the ionospheric storm scale (I-scale) based on foF2, the studied results are shown that the occurrence probability of each I-scale among studied stations are close one another. The occurrence probability (Pocc) of quiet situations occur maximally about 71%. The Pocc of Ip3 occur minimally about 0.3%. The Pocc of IP1, IN1, and IN2 are about 14%, 12.9%, and 1.4%.