Composition analysis of liquid particles in the Arctic stratosphere under synoptic conditions

C. Weisser (1) , K. Mauersberger (1) , J. Schreiner (1) , N. Larsen (2) , F. Cairo (3) , A. Adriani (4) , J. Ovarlez (5) , T. Deshler (6)

1 MPIK - Max Planck Institute for Nuclear Physics
2 DMI - Danish Meteorological Institute
3 ISAC - Istituto di Scienze dell'Atmosfera e del Clima
4 IFSI - Istituto di Fisica dello Spazio Interplanetario
5 LMD - Laboratoire de Météorologie Dynamique (UMR 8539)
6 Department of Atmospheric Science [Laramie]

Synoptic scale polar stratospheric clouds (PSCs) that formed without the presence of mountain lee waves were observed in early December 2002 from Kiruna/Sweden using balloon-borne instruments. The physical, chemical, and optical properties of the particles were measured. Within the PSC solid particles existed whenever the temperature was below the equilibrium temperature for nitric acid trihydrate and liquid particles appeared when the temperature fell below an even lower threshold about 3 K above the frost point with solid particles still present. The correlation of liquid supercooled ternary solution aerosols with local temperatures is a pronounced feature observed during this flight; average molar ratios H₂O/HNO₃ were somewhat higher than predicted by models. In addition HCl has been measured for the first time in liquid aerosols. The chlorine isotope signature served as a unique tool to identify unambiguously HCl dissolved in STS particles. Within a narrow temperature range of about three degrees above the frost point, the measured average amount of HCl in liquid particles is below 1 weight%.

Domaines: Océan, Atmosphère

C. Weisser, K. Mauersberger, J. Schreiner, N. Larsen, F. Cairo, et al.. Composition analysis of liquid particles in the Arctic stratosphere under synoptic conditions. Atmospheric Chemistry and Physics, 2006, 6 (3), pp.696. ⟨hal-00328421⟩