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arXiv · 1608.02494

Measurements of the Atmospheric Electric Field through a Triangular Array and the Long-range Saharan Dust Electrification in Southern Portugal

H. G. Silva·F. Lopes·S. Pereira·S. M. Barbosa·K. Nicoll·M. Collares Pereira·R. G. Harrison
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Abstract

Atmospheric electric field (AEF) measurements were carried out in three different sites forming a triangular array in Southern Portugal. The campaign was performed during the summer characterized by Saharan dust outbreaks; the 16th-17th July 2014 desert dust event is considered here. Evidence of long-range dust electrification is attributed to the air-Earth electrical current creating a positive space-charge inside of the dust layer. An increase of ~23 V/m is observed in AEF on the day of the dust event corresponding to space-charges of ~20-2 pCm-3 (charge layer thicknesses ~10-100 m). A reduction of AEF is observed after the dust event.

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H. G. Silva, F. Lopes, S. Pereira, S. M. Barbosa, K. Nicoll, M. Collares Pereira, R. G. Harrison. 2016-08-08. Measurements of the Atmospheric Electric Field through a Triangular Array and the Long-range Saharan Dust Electrification in Southern Portugal. https://arxiv.org/abs/1608.02494

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