Alignment of atmospheric mineral dust due to electric field - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Atmospheric Chemistry and Physics Année : 2007

Alignment of atmospheric mineral dust due to electric field

Résumé

Optical polarimetry observations on La Palma, Canary Islands, during a Saharan dust episode show dichroic extinction indicating the presence of vertically aligned particles in the atmosphere. Modelling of the extinction together with particle orientation indicates that the alignment could have been due to an electric field of the order of 2 kV/m. Two alternative mechanisms for the origin of the field are examined: the effect of reduced atmospheric conductivity and charging of the dust layer, the latter effect being a more likely candidate. It is concluded that partial alignment may be a common feature of Saharan dust layers. The modelling indicates that the alignment can significantly alter dust optical depth. This "Venetian blind effect" may have decreased optical thickness in the vertical direction by as much as 10% for the case reported here. It is also possible that the alignment and the electric field modify dust transport.
Fichier principal
Vignette du fichier
acp-7-6161-2007.pdf (278.26 Ko) Télécharger le fichier
Origine : Accord explicite pour ce dépôt
Loading...

Dates et versions

hal-00296401 , version 1 (18-06-2008)

Identifiants

  • HAL Id : hal-00296401 , version 1

Citer

Z. Ulanowski, J. Bailey, P. W. Lucas, J. H. Hough, E. Hirst. Alignment of atmospheric mineral dust due to electric field. Atmospheric Chemistry and Physics, 2007, 7 (24), pp.6161-6173. ⟨hal-00296401⟩

Collections

INSU EGU
94 Consultations
225 Téléchargements

Partager

Gmail Facebook X LinkedIn More