Dr Purushottam Bhawre
@mphighereducation.nic.in
Assistant Professor Department of Physics
Rani Durgawati Govt P G College Mandla
RESEARCH INTERESTS
Astronomy and astrophysics, Atmospheric Physics, Earth Science, Geomagnetism, space weather
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
A. K. Gwal, Suryanshu Choudhary, and Purushottam Bhawre
CRC Press
P K Purohit, Azad A Mansoori, Parvaiz A Khan, Roshni Atulkar, Purushottam Bhawre, Sharad C Tripathi, Prakash Khatarkar, Shivangi Bhardwaj, A M Aslam, Malik A Waheed,et al.
IOP Publishing
The geomagnetic storm represents the most outstanding example of solar wind- magnetospheric interaction, which causes global disturbances in the geomagnetic field as well as triggers ionospheric disturbances. We study the behaviour of ionospheric Total Electron Content (TEC) during the geomagnetic storms. For this investigation we have selected 47 intense geomagnetic storms (Dst ≤ -100nT) that were observed during the solar cycle 23 i.e. during 1998- 2006. We then categorized these storms into four categories depending upon their solar sources like Magnetic Cloud (MC), Co-rotating Interaction Region (CIR), SH+ICME and SH+MC. We then studied the behaviour of ionospheric TEC at a mid latitude station Usuda (36.13N, 138.36E), Japan during these storm events produced by four different solar sources. During our study we found that the smooth variations in TEC are replaced by rapid fluctuations and the value of TEC is strongly enhanced during the time of these storms belonging to all the four categories. However, the greatest enhancements in TEC are produced during those geomagnetic storms which are either caused by Sheath driven Magnetic cloud (SH+MC) or Sheath driven ICME (SH+ICME). We also derived the correlation between the TEC enhancements produced during storms of each category with the minimum Dst. We found the strongest correlation exists for the SH+ICME category followed by SH+MC, MC and finally CIR. Since the most intense storms were either caused by SH+ICME or SH+MC while the least intense storms were caused by CIR, consequently the correlation was strongest with SH+ICME and SH+MC and least with CIR.
P. K. Purohit, Azad A. Mansoori, Parvaiz A. Khan, Purushottam Bhawre, Sharad C. Tripathi, A. M. Aslam, Malik A. Waheed, and A. K. Gwal
IEEE
The geomagnetic storm represents the most outstanding example of solar wind- magnetospheric interaction, which causes global disturbances in the geomagnetic field as well as the trigger ionospheric disturbances. Under this problem we study the behaviour of ionospheric Total Electron Content (TEC) during the geomagnetic storms. For the present investigation we have selected 47 intense geomagnetic storms (Dst ≤ -100nT) that during the solar cycle 23 i.e. during 1998- 2006. We then categorized these storms into four categories depending upon their solar sources like Magnetic Cloud (MC), Co-rotating Interaction Region (CIR), SH+ICME and SH+MC. We then studied the behaviour of ionospheric TEC at a mid latitude station Usuda (), Japan during these storm events. During our study we found that the smooth variations in TEC are replaced by rapid fluctuations and the value of TEC is strongly enhanced during the time of these storms belonging to all the four categories. However, the greatest enhancements in TEC are produced during those geomagnetic storms which are either caused by Sheath driven Magnetic cloud (SH+MC) or Sheath driven ICME (SH+ICME). We also derived the correlation between the TEC enhancements produced during storms of each category with the minimum Dst. We found the the strongest correlation exists for the SH+ICME category followed by SH+MC, MC and finally CIR. Since the most intense storms were either caused by SH+ICME or SH+MC while the least intense storms were caused by CIR, consequently the correlation was strongest with SH+ICME and SH+MC and least with CIR.
Azad A. Mansoori, Parvaiz A. Khan, Purushottam Bhawre, A. K. Gwal, and P. K. Purohit
IEEE
The ionospheric behavior is controlled by the solar output, therefore the ionospheric variability follows a synchronous variation with the solar activity. The solar activity follows a periodic long term variability, which therefore can be expected to be reflected in the ionospheric behavior. We investigated the variability of ionosphere by using the GPS derived Total Electron Content (TEC) at a mid latitude station Usuda (36.13N, 138.36E), Japan during the sunspot cycle 23 and 24. The solar activity is characterized by a number of activity indices, however for the present study we have used five solar activity indices relevant to the ionospheric studies namely, Sunspot Number (Rz), Solar radio Flux (F 10.7 cm), EUV Flux (26-34 nm), Flare Index and CME Occurrences. The long term variation of the solar activity indices were compared with the variability of ionospheric TEC, and it was found that ionospheric TEC and solar activity variations occur synchronously. The correlation analysis was performed to access the magnitude of correlation between the long term solar cycle variations and the ionospheric behavior. From the analysis we found that GPS derived TEC follows a strong correlation with the solar activity indices. The correlation was found to be remarkably strongest during the deep minimum of the cycle 24 i.e 2007-2008.
Prakash Khatarkar, Purushottam Bhawre, Pravaiz A. Khan, Azad A. Mansoori, Shweta Mukherjee, P. K. Purohit, and A. K. Gwal
American Scientific Publishers
N.K. Sethi, R.S. Dabas, Purshottam Bhawre, and S.K. Sarkar
Elsevier BV