Study The Relation Of Ionospheric Scintillation And TEC Depletion Over South China Based On GPS-TEC Data

In South China areas of Guangdong province,Guangxi province and Hainan are located under the northern crest of Earth's equatorial anomaly,the ionospheric activity is very active,which is a high incidence of ionospheric scintillation and TEC(Total Electron Content)depletion.Using the data of ionospheric scintillation and TEC observed from January 2011 to December 2012,and January 2015 to December 2015 by a monitor seting at Shenzhen GPS Station,the temporal and spatial distributions of scintillation with TEC depletion,scintillation with no TEC depletion,and TEC depletion with no scintillation along are discussed simultaneously in this paper,and the reason of temporal and spatial distribution of these three phenomena is analyzed by using the mechanism of the equatorial ionosphere irregularity in this region.At the same time,in order to explore the internal relations between the two phenomena of ionospheric scintillation and TEC depletion,through the statistics of the simultaneous events of the ionospheric scintillation and TEC depletion from January to December 2015,calculating the corresponding change rate of TEC,then analysis the relationship between change rate of TEC and scintillation.the main research results are summarized as follows:1.There are obvious seasonal,local time and latitudinal dependence when the occurrence of three phenomena for scintillation with TEC depletion,scintillation with no TEC depletion,and TEC depletion with no scintillation;The three phenomena mainly in spring and fall for seasonal dependence;We also find that scintillation with TEC depletion,scintillation with no TEC depletion,and TEC depletion with no scintillation occurred mainly from geographic 19°N to 23°N,21°N to24°N,24°N to 26°N,respectively.In addition,scintillation with TEC depletion,scintillation with no TEC depletion,and TEC depletion with no scintillation occurred mainly from 20:00LT to 22:00LT,21:00LT to 23:00LT,22:30LT to 23:30LT,respectively.2.The seasons,temporal and spatial distribution of three phenomena of scintillation with TEC depletion,scintillation with no TEC depletion,and TEC depletion with no scintillation are mainly controlled by east pre-reversal enhancement.3.The temporal and spatial distribution characteristics of three phenomena of scintillation with TEC depletion,scintillation with no TEC depletion,and TEC depletion with no scintillation are in line with the evolution process of irregularity over South China.4.The larger change rate of TEC,the greater the ionospheric scintillation,which is due to the occurred plasma bubble at the edge of the horizontal density gradient,and the small irregular body is mass occurred resulting in violent scintillation.