In situ detection of electrified aerosols in the upper troposphere and stratosphere 1LPC2E-CNRS/University of Orléans, 3A avenue de la recherche scientifique, UMR7328, 45071 Orléans cedex 2, France
18 Nov 2013
2Indian Institute of Technology, Kanpur, Center for Environmental Science and Engineering, Kanpur, India
3University of Bath, Department of Electronic and Electrical Engineering, Claverton Down, Bath, BA2 7AY, UK
4University of Reading, Department of Meteorology, Reading RG6 6BB, UK
Received: 16 December 2012 – Published in Atmos. Chem. Phys. Discuss.: 18 March 2013 Abstract. Electrified aerosols have been observed in the lower troposphere and in the
mesosphere, but have never been detected in the stratosphere and upper
troposphere. We present measurements of aerosols obtained during a balloon
flight to an altitude of ~ 24 km. The measurements were
performed with an improved version of the Stratospheric and Tropospheric Aerosol Counter (STAC) aerosol counter dedicated to
the search for charged aerosols. It is found that most of the aerosols are
charged in the upper troposphere for altitudes below 10 km and in the
stratosphere for altitudes above 20 km. Conversely, the aerosols seem to be
uncharged between 10 km and 20 km. Model calculations are used to quantify
the electrification of the aerosols with a stratospheric aerosol-ion model.
The percentages of charged aerosols obtained with model calculations are in
excellent agreement with the observations below 10 km and above 20 km.
However, the model cannot reproduce the absence of electrification found in
the lower stratosphere, as the processes leading to neutralisation in this
altitude range are unknown. The presence of sporadic transient layers of
electrified aerosol in the upper troposphere and in the stratosphere could
have significant implications for sprite formation.
Revised: 17 August 2013 – Accepted: 16 October 2013 – Published: 18 November 2013
Citation: Renard, J.-B., Tripathi, S. N., Michael, M., Rawal, A., Berthet, G., Fullekrug, M., Harrison, R. G., Robert, C., Tagger, M., and Gaubicher, B.: In situ detection of electrified aerosols in the upper troposphere and stratosphere, Atmos. Chem. Phys., 13, 11187-11194, doi:10.5194/acp-13-11187-2013, 2013.