Correlation Analysis Between Ionospheric Scintillation And TEC Depletion In South China And The Pragmatic Study Of Ionosonde Data

According to the data of ionospheric scintillation and total electron content(TEC) observed by a monitor set at Shenzhen Station(22.59°N,113.97°E) as a part ofMeridian Space Weather Monitoring Project in equatorial anomaly regions in SouthChina, we have a statistical analysis on TEC depletion, and TEC depletion andionospheric scintillation correlation analyzes were focused, although TECenhancements are introduced. The drift characteristics of plasma bubble also bediscussed by means of TEC depletion. Simultaneously, according to the data ofionosonde data observed from January,2011to August,2013by a monitor set atWuhan（30.5°N,114.4°E）and Hainan（19.5°N,109.1°E）as a part of Meridian SpaceWeather Monitoring Project, the influence of solar flares on ionosphere that more thanclass M5.0are analyzed by means of the low layer electron density.According to the data of ionospheric scintillation and total electron content(TEC) observed from January,2011to December,2012, the relationship between theTEC depletion and the ionospheric scintillation at the nighttime in South China wasanalyzed. The results show that (1)TEC depletions occur mainly in the equinox season,there occurs frequent TEC depletion simultaneously with the scintillation;(2)thesimultaneous occurrence of strong scintillation (S4>0.6) and TEC depletion is morefrequent than that of weak scintillation (0.2<S4≤0.6) and TEC depletion;(3)when thesimultaneous occurrence appears, a positive duration correlation apparently existsbetween the TEC depletion and the ionospheric scintillation; and (4)although TECenhancements are observed at the nighttime in South China, they have no significantcorrelation with the ionospheric scintillation.The drift characteristics of plasma bubble also be discussed by means of TECdepletion, the results show that(1)TEC depletion could be used to predict theemergence of ESF,(2)the plasma bubble trend towards high latitude before22:00LT,but the plasma bubble trend towardslow latitude after22:00LT in South China.According to the data of ionosonde data observed from January,2011to August,2013, the influence of solar flares on ionosphere that more than class M5.0areanalyzed, the results show that:(1)The ionograms’trace of Wuhan and Hainan stationwere disappeared caused by the solar flare of class X2.2which erupted on February15th,2011; Morever, there is a minimum frequency gap between a solar flare’day anda quiet day, with the former higher than the latter.(2)The class and the durations of solar flare are all the main factors which have a positive effect on ionospheric electrondensity. It indicates that a small flare that has a long time maybe has an stronger effecton ionosphere than a big flare that has an short duration.(3)The local time of flarecan also effect the increment of ionospheric electron density, the results show that aflare that occurs at noon time has an stronger effect on ionosphere.