Fairweather atmospheric electricity at Antarctica during local summer as observed from Indian station, Maitri

Abstract

Surface measurements of the atmospheric electrical parameters like Maxwell current, electric field and conductivity studied at the Indian station, Maitri (70.75 • S, 11.75 • E, 117 m above mean sea level), Antarctica, during austral summer have been analyzed for the years 2001 to 2004. A total of 69 days were selected which satisfied the 'fairweather' conditions, i.e., days with absence of high winds, drifting or falling snow, clouds, and fog effects. The diurnal variation curve of electric field and vertical current averaged for 69 fairweather days is a single periodic with a minimum at 03:00 UT and a maximum near 19:00 UT, which is very similar to the Carnegie curve. The correlation coefficient between these measured parameters has a high value (more than 0.9) for all the days. During fairweather days the measured current and field variations are similar and hence it is clear that the conductivity is more or less stable. During magnetically disturbed days, the dawn-dusk potential drop has clear influences on the diurnal variation and it modifies the conductivity. Apart from the day-to-day variation in low latitude thunderstorm activity, there are diurnal, seasonal, inter-annual variations in the electric potential and the currents, as well as solar influences on the measured parameters. This study will help us to examine the impact of solar and geophysical phenomena like solar flares, geomagnetic storms and substorms on the global electric circuit.

First results of fair-weather atmospheric electricity measurements in Northeast India

“…It can be readily observed that E is highly dependent on local variation of atmospheric conductivity compared to J z . This is the reason why the variation of J z is often treated as the representative of ionospheric potential over E. Nevertheless, there are evidences of global signatures in measurements of vertical potential gradient in fair-weather in remote locations, far from sources of pollution, and during fair-weather conditions (Frank-Kamenetsky et al 2001;Reddell et al 2004;Burns et al 2005;Panneerselvam et al 2007).…”

Anomalous diurnal variation of atmospheric potential gradient and air‐Earth current density observed at Maitri, Antarctica

“…Panneerselvam et al . [] presented another set of results on the diurnal variation of the PG and Maxwell current density. In their report, the mean diurnal variations were obtained from 69 fair‐weather days from the austral summer months distributed as 10, 12, 10, and 37 numbers of days during the years 2001–2004, respectively.…”

“…These authors observed neither a peak PG at ~13 UT observed by Deshpande and Kamra [] nor a depression in the prenoon hours observed by Panneerselvam et al . [] and Jeeva et al . [].…”

Investigation of the Influence of Galactic Cosmic Rays on Clouds and Climate in Antarctica

“…2A (Weimer, 2005;Anil Kumar et al, 2009;Tinsley 1996, Rycroft et al, 2012. In an earlier work, Panneerselvam et al, (2007b) mathematically differentiated later contributions from Maitri observations. It is well known that the current density J z is proportional to the overhead ionospheric potential (V i ).…”

“…Deshpande and Kamra (2001) reported the data for 34 days in 1997. Panneerselvam et al (2007b) analyzed the data in 2001-2004. Using the rainfall data obtained from different…”