Evaluation of long term solar activity effects on GPS derived TEC

27th IUPAP Conference on Computational Physics

物理学;计算机科学

Mansoori, Azad A.^1 ; Khan, Parvaiz A.^2 ; Ahmad, Rafi^3 ; Atulkar, Roshni^3 ; Aslam, A.M.^1 ; Bhardwaj, Shivangi^3 ; Malvi, Bhupendra^1 ; Purohit, P.K.^3 ; Gwal, A.K.^1

Space Science Laboratory, Department of Physics and Electronics, Barkatullah University, Bhopal

462026, MP, India^1

Department of Electronics and Communication Engineering, Islamic University of Science and Technology, Pulwama

JK

192122, India^2

National Institute of Technical Teachers ' Training and Research, Bhopal

MP

462002, India^3

关键词: Correlation analysis;    Ionospheric variability;    Long term behaviours;    Long-term variability;    Mid-latitude station;    Solar activity index;    Strong correlation;    Total electron content;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/759/1/012069/pdf
DOI  :  10.1088/1742-6596/759/1/012069

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

The solar activity hence the solar radiance follows a long term periodic variability with eleven years periodicity, known as solar cycle. This drives the long term variability of the ionosphere. In the present problem we investigate the long term behaviour of the ionosphere with the eleven year cyclic solar activity. Under the present study we characterize the ionospheric variability by Total Electron Content (TEC) using measurements made by Global Positioning System (GPS) and solar cycle variability by various solar activity indices. We make use of five solar activity indices viz. sunspot number (Rz), solar radio Flux (F10.7 cm), EUV Flux (26-34 nm), flare index and CME occurrences. The long term variability of these solar activity indices were then compared and correlated with the variability of ionospheric TEC, at a mid latitude station, Usuda (36.13N, 138.36E), of Japan, during the solar cycle 23 and ascending phase of cycle 24. From our study, we found that long term changes in the ionospheric TEC vary synchronously with corresponding changes in the solar activity indices. The correlation analysis shows that all the solar activity indices exhibit a very strong correlation with TEC (R =0.76 -0.99). Moreover the correlation between the two is stronger in the descending phase of the solar cycle. The correlation is found to be remarkably strongest during the deep minimum of the solar cycle 24 i.e. between 2007- 2009. Also we noticed a hysteresis effect exists with solar radio flux (F10.7 cm) and solar EUV flux (26-34 nm). This effect is absent with other parameters.