Seasonal features of ultrafine particle volatility in the coastal Antarctic troposphere

Abstract

Abstract. The size distribution and volatility of ultrafine aerosol particles were measured using scanning mobility particle sizer and thermodenuder at Syowa Station during the 46–47 Japanese Antarctic Research Expeditions (2005–2007). The relative abundance of non-volatile particles in a 240 C scan was approximately 20 % during the summer, whereas the abundance of non-volatile particles increased by >90 % during winter–spring. During the summer, most ultrafine particles were NH4+, SO42− and CH3SO3−, while major constituents of ultrafine particles were sea-salts (Na+ and Cl−) in winter–spring. Therefore, the seasonal feature of volatility of ultrafine particles at Syowa might result from seasonal variations of the major aerosol constituents. Although the relative abundance of non-volatile particles was usually higher during winter–spring, the abundance dropped occasionally to <30 %. The lower abundance of non-volatile ultrafine particles during winter–spring corresponded to the lower number concentration of ultrafine particles and transport from the free troposphere over Antarctica.