Dipartimentodi Fisica, Università di L'Aquila, Italy

The physical condition of polar stratospheric aerosols is of great importance both for the modelling of surface chemistry reactions and for the understanding of particle production and evaporation in the polar vortex. The particles can be either liquid, supercooled liquids or solid material at different heights and temperatures. Since a solid particle can survive much longer when temperature rises above the freezing point, whereas liquid particles will evaporate quickly at temperatures above the condensation temperature, the knowledge of the physical state is an important parameter to estimate the contribution to heterogenous chemistry of the different aerosol types observed.