Electrical conductivity of the stratosphere over Hyderabad, India: Results from Balloon borne measurements

Abstract

<span style="font-size:11.0pt;mso-bidi-font-size: 10.0pt;font-family:" times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";="" mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa"="" lang="EN-US">The stratospheric conductivity is an important parameter of the global electric circuit. In this paper, the stratospheric conductivity measurements are presented, which were made using high altitude balloon flights from Hyderabad (geographic 17.5°N, 78.5°E; magnetic lat 8.5°N), India as a part of the IMAP (1982-1994) program of India. The vertical profiles of ion conductivity were measured from Hyderabad during periods with different solar activity levels and during different seasons using different techniques. It was observed that conductivity values in stratosphere are larger in high solar activity period as compared to low solar activity period. This is similar in nature to the observations from mid-latitudes. The observed positive correlation with solar activity is discussed in terms of composition changes due to the change in intensity of the UV (200-300 nm) radiation with solar activity. It was found that the dissociation of heavy cluster ions to lighter ions, as conjectured by Gupta [Solar cycle variation of stratospheric conductivity over low latitude, <i>Adv Space Res</i> (<i>UK</i>), 26 (2000.) pp 1225–1229] is the main reason for the observed positive correlation of stratospheric conductivity with solar activity. No significant seasonal effect was noticed. In addition, conductivity profile obtained from Hyderabad is compared to that obtained from Cachoeira Paulista, Brazil.</span>