REGIONAL CHARACTERISTICS OF GEOMAGNETIC STORM AND ITS EFFECTS ON SOME TROPOSHERIC WEATHER PARAMETERS

Abstract

Geomagnetic storm effect on the lower Atmosphere has been little studied. In this work an attempt was being made to understand the effects of geomagnetic storm on the troposphere weather system, using the disturbed storm time (DST) index data, for storm periods between 6th and 14th of Nov, 2014. The analysis was considered for different pressure heights which are 600 mbar, 850 mbar and 1000 mbar. The storm days were classified into moderate storm (-50 nT to -100 nT), intense storm (-100 nT to -250 nT) and super storm (-250 nT to -500 nT) to see the effect of the geomagnetic storm on the Tropospheric weather system. This analysis was done for the data obtained from different regions in the low latitude (0-20o); mid latitude (22-59o) and; polar region (60o and above). Cross correlation function was used to check for the lagged correlation and lag time response of the parameters to the storm event i.e, results obtained shows that the storm commenced at 2100 UTC on Julian day 312 (Nov. 8, 2004) while an initial phase value -71 nT, called the sudden storm commencement (scc), the disturbance increased into the main phase to a Dst value -374 nT at 0600 UTC on Julian day 313 (Nov. 9, 2004) and also another main phase of Dst -263 nT on the same Julian day 315 (Nov. 11, 2004) at 1000 UTC, and observed recovery phase started from 1800 UTC on the same day 315 (Nov. 11, 2004). The varied responses of the parameters due to the effects of geomagnetic storm on the tropospheric weather parameters are more pronounced in the High latitude Regions and these regions had little similar responses to the Geomagnetic storms. The general results conclusively shows a non-response of the weather parameters to geomagnetic storm at low latitude stations and mid_latitude station, while at the high latitudes region, there are some responses of rise in temperature. Relative humidity response to geomagnetic storm was more pronounced and observed at the high-latitude stations.