Geomagnetic-induced tropopause temperature and wind variation over low latitude

Abstract

The present study reports the effect of geomagnetic storm on 200 mb altitude temperature and wind at a low latitude (8.7°N, 77.8°N) Indian region. The severe and strong geomagnetic storm (Dst < – 100 nT) between 2000 and 2005 has been studied. The impact of the geomagnetic activity on temperature and wind variation is affected by the QBO (Quasi-Biennial Oscillation) phase. The tropopause temperature increases by ~ 2.5 K during W-phase of QBO and decreases by ~ 1.5 K during E-phase of QBO. The time lag between the onset of the event and the maximum change in temperature becomes a minimum during the transition phase of QBO. The horizontal wind velocity shows a pronounced effect over the east coast of India. The effect has not been observed during the onset of the south-west monsoon. The vertical wind velocity at 200 mb shows increase (or decrease) during W- (or E-) phase of the event.