Aerosol samples were collected using a TischTE-5170-VBL high volume aerosol sampler, modified to collect 12 replicate aerosol samples on 47mm open-face filter holders loaded with acid-washed Whatman-41 ashless filters for trace element analysis. The sampler was installed above the bridge on the bow of the ship to best sample clean air while avoiding sea spray. Aerosol collection was limited to times when the relative wind direction precluded exhaust contamination from the ship’s smokestack from reaching the sampler.
Aerosol samples were collected during three sampling periods on 14-15 Aug., 24 Aug-1 Sept., and 7-15 Sept. 2011. In chronological order the three sampling volumes of air filtered, per circular filter, were 48.4, 207.8 and 273.5m3 respectively. In addition to these filters, pre-combusted (480oC, >10 hours) quartz micro fiber (Whatman QMA) filters for the analysis of Hg (reported elsewhere) were deployed during 17-23 Aug., 2-14 Sept., and 16 Sept., 2011. In chronological order the three sampling volumes of air filtered, per circular filter, were 234.1, 280.7, and 54.6 m3 respectively. The W41 47mm aerosol samples and GFF 47mm filters were stacked three-high in a plastic petrie dish and counted for 7Be. As described above, this configuration was calibrated with a commercially prepared mixed solution of known gamma activities.