Aerosol sonde and lidar observations of stratospheric aerosol and polar stratospheric cloud above Ny-Alesund

Abstract

Balloon borne aerosol sonde observation and lidar observations were preformed at Ny-Alesund, Norway in the winters of 2002 03 and 2007 08. In the winter of 2002 03, the aerosol layers with the increment of depolarization ratio were observed at the lower stratosphere below 15 km height by lidar. The effective radius of stratospheric aerosol estimated from aerosol sonde observations showed high values of 0.17-0.24 μm in radius in the height range. The temperature in the height range was remarkably higher than the formation temperature of polar stratospheric cloud (PSC). The depolarized aerosol layer might be volcanic aerosol by the eruption of Mt. El Reventador. The average value of effective radius of stratospheric aerosol in the height range of 10-25 km was estimated to be 0.12 μm. In the winter of 2007 08, PSC events were frequently detected. Both solid and liquid PSC detected by lidar on January 9, 2008 showed that they experienced almost the same temperature history. They might be affected by meso-scale temperature perturbations such as gravity waves.