Portal de Periódicos da CAPES

The geoelectric field at Vostok, Antarctica: its relation to the interplanetary magnetic field and the cross polar cap potential difference

1999; Elsevier BV; Volume: 61; Issue: 18 Linguagem: Inglês

10.1016/s1364-6826(99)00089-9

1879-1824

A. V. Frank‐Kamenetsky, G. B. Burns, О. А. Troshichev, V. O. Papitashvili, Edgar A. Bering, John French,

Earthquake Detection and Analysis

The vertical geoelectric field measured at Vostok, Antarctica (78.5°S, 107°E, L=75.0) over the 13 month interval May 1979–May 1980 is correlated with the interplanetary magnetic field (IMF) components By and Bz at times when Vostok is connected to the dayside magnetosphere. No significant association with IMF Bx is found. The interaction of the solar wind and the Earth's magnetic field generally results in anti-sunward plasma flow in the high-latitude, polar ionosphere driven by a dawn-to-dusk, cross polar cap potential difference pattern. Using the IZMEM model to infer the contribution of the cross polar cap potential difference to the potential difference between the ionosphere and the ground at Vostok for the measured IMF conditions, we show that this provides a viable mechanism for the IMF associations found. We demonstrate that the direct association of the geoelectric field with the cross polar cap potential difference is independent of a result (Park, 1976. Solar magnetic sector effects on the vertical atmospheric electric field at Vostok, Antartica. Geophysical Research Letters 3(8), 475–478) showing an ∼15% decrease in the vertical geoelectric field measured at Vostok, 1–3 days after the passage of IMF sector boundaries. Evidence is also presented supporting the Park result, for which a mechanism is yet to be confirmed.