HR: 0800h
AN: A11B-0037    [Abstracts]
TI: Composition of Aerosol Particles From the South Pole During ANTCI
AU: * Arimoto, R
EM: arimoto@cemrc.org
AF: Carlsbad Environmental Monitoring & Research Center, New Mexico State University 1400 University Drive, Carlsbad, NM 88220 United States
AU: Khaing, H
EM: hnin@cemrc.org
AF: Carlsbad Environmental Monitoring & Research Center, New Mexico State University 1400 University Drive, Carlsbad, NM 88220 United States
AU: Schloesslin, C
AF: Carlsbad Environmental Monitoring & Research Center, New Mexico State University 1400 University Drive, Carlsbad, NM 88220 United States
AU: Raccah, F
EM: raccah@eml.doe.gov
AF: Environmental Measurements Laboratory Dept of Homeland Security, 201 Varick Street, New York, NY 10014-4811 United States
AB: As part of the Antarctic Tropospheric Chemistry Investigation (ANTCI), daily, high-volume, aerosol samples were collected from 22 November to 23 December 2003 at the South Pole Clean Air Facility. The samples were shipped frozen to the Carlsbad Environmental Monitoring & Research Center where they were analyzed for several major ions (nitrate, sulfate, methanesulfonate), up to thirty-three trace elements, and three radionuclides ($^{210}$Pb, $^{210}$Po, and $^{7}$Be). These samples were collected at the same site and with the same bulk collectors used during two field experiments conducted in 1998 and 2000 for a related program, the Investigation of Sulfur Chemistry in the Antarctic Troposphere (ISCAT). The $^{7}$Be activities were consistent with the long-term record produced by the Environmental Measurements Laboratory (EML); in particular, a slight decrease observed in the ANTCI $^{7}$Be samples compared with the ISCAT samples is in keeping with decade-scale trends in sunspot activity. The $^{210}$Pb activities were towards the high end of long-term EML record, but they were similar to the earlier ISCAT data. The arithmetic mean sulfate (124 ng m$^{-3}$), and methanesulfonate (MSA, 9.1 ng m$^{-3}$) concentrations were comparable to those observed during the ISCAT experiments, and the MSA/sulfate ratios for all experiments were generally similar, but there were several days during ANTCI (29 November to 3 December) on which high MSA concentrations and high MSA/sulfate concentration ratios occurred. Sodium concentrations, an indicator of atmospheric sea-salt, also were high in that set of samples, suggesting impacts from relatively fresh maritime air. Most notably, the arithmetic mean nitrate concentration (250 ng m$^{-3}$) during ANTCI was higher than that for either of the ISCAT data sets (39 ng m$^{-3}$ for ISCAT 1998 and 150 ng m$^{-3}$ for ISCAT 2000). Furthermore, while several peaks in nitrate were synchronous with MSA and sulfate, the last two samples collected (21 to 23 December 2003) had high nitrate but not high MSA or sulfate. In addition, the concentrations of elements typically associated with mineral aerosol, such as Al, Fe, K, etc. were roughly 5-times higher in the ANTCI samples compared with those collected during ISCAT. Several elements, including Pb, Sb, and Zn, that have strong anthropogenic sources also were higher during ANTCI than in the previous studies. These results indicate that there were relatively strong continental influences during ANTCI as well as the aforementioned maritime effect.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0305 Aerosols and particles (0345, 4801)
DE: 0322 Constituent sources and sinks
DE: 0330 Geochemical cycles
DE: 0365 Troposphere--composition and chemistry
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting