Spatial distributions and mixing states of aerosol particles in the summer Antarctic troposphere

• Main Authors: Keiichiro Hara, Naohiko Hirasawa, Takashi Yamanouchi, Makoto Wada, Andreas Herber
• Format: Article in Journal/Newspaper
• Language: English; Japanese
• Published: National Institute of Polar Research 2010
• Subjects: Geography (General); G1-922; Antarctic; Austral; Kohnen; Neumayer; Syowa Station; The Antarctic; Antarc*
• Online Access: https://doi.org/10.15094/00009581; https://doaj.org/article/e4654f8f2f8a4ebbbfc5919fa37d3012

Airplane-borne atmospheric measurements (ANTSYO-II: AGAMES) were carried out in the Antarctic regions in December 2006-January 2007. Aerosol measurements and direct aerosol sampling were done around Neumayer, Kohnen, and S17 (close to Syowa Station). Aerosol samples for individual particle analysis were obtained from 28 scientific flights from near ground to 24000 ft (ca. 7500 m) during the campaign using a one-stage aerosol impactor. Preliminary results of individual particle analysis indicate that sulfate particles (mostly H_2SO_4) were dominant aerosol constituents in all flights. In addition, combustion-origin aerosol particles (e.g., soot and sulfate containing K) were identified even in the upper troposphere in Antarctic regions. Also, mineral-like and sea-salt-like particles were identified in the free troposphere. This strongly suggests that combustion-origin aerosol particles and mineral particles were transported from low- and mid-latitudes toward Antarctic regions via the upper free troposphere in the austral summer. Spatial distributions of the number concentrations of aerosol particles indicate horizontal gradient of aerosols from the continent to the open water area due to emission of sea-salt particles from the sea surface.