Equatorial electrojet in the Indian region during the geomagnetic storm of 13–14 November 1998

Journal of Earth system science

R K Choudhary2²  H Chandra1¹  Som Sharma1¹  R G Rastogi1¹ 

[1] Physical Research Laboratory, Ahmedabad 380 009, India.$$;Space Physics Laboratory, Vikram Sarabhai Space Centre, Thiruvananthapuram 695 002, India.$$

关键词: Equatorial electrojet;    equatorial ionosphere;    geomagnetic storms;   

DOI  :  

学科分类：天文学(综合)

来源: Indian Academy of Sciences

【 摘 要 】

The geomagnetic storm of November 1998 is a unique event where IMF-Bz remained southward withvalues exceeding –15 nT for more than a day. The SYM/H index decreased from about 07 hr on 13November 1998 reaching a minimum of about –120 nT around midnight of 13–14 November 1998.Features of the equatorial electrojet in the Indian region are studied during the geomagnetic storm eventof 13–14 November 1998, based on the geomagnetic data from the chain of observatories in India. Suddennorthward turning of IMF-Bz for a very short duration around 08 hr on 13 November 1998 resultedin a small and very short duration counter electrojet. A strong (–50 nT) and a long duration counterelectrojet, right from 08 to 13 hr on 14 November 1998 was observed resulting in the absence of equatorialEs at Thumba. Absence of the equatorial ionization anomaly was also observed as seen from theionograms over Thumba and ionspheric data from Ahmedabad. The delayed effect on 14 November 1998is due to the disturbance dynamo effect.

【 授权许可】

Unknown