Supporting information

Transcription

1 Supporting information Chemistry of urban grime: Inorganic ion composition of grime vs. particles in Leipzig, Germany Alyson M. Baergen, 1 Sarah A. Styler, Dominik van Pinxteren, Konrad Müller, Hartmut Herrmann and D.James Donaldson * 1, 1. Department of Chemistry, University of Toronto, 8 St George St. Toronto, ON, CANADA M5S H. Leibniz-Institut für Troposphärenforschung (TROPOS), Atmospheric Chemistry Dept.(ACD), Permoserstr. 15, 18 Leipzig, Germany.. Department of Physical and Environmental Sciences, University of Toronto Scarborough, 15 Military Trail, Toronto, ON M1C 1A 7 Pages Supporting Figures S1

2 a) b) c) Particle inlet UV-transparent cover Light-exposed tray Stainless steel sheet Light-shielded tray Figure S1a shows a photograph of the sampling container positioned in downtown Leipzig, with the film sampler on the roof at the left, next to the inlet for particle samples. Figure S1b shows a close up of the upper two layers of the sampler, without the side flaps mounted on one side. The UV-transparent cover over the top layer of beads is shown at the top above the first tray of beads. Beneath this is a sheet of stainless steel that shields the second layer of glass beads from sunlight. The separate bead compartments in the second layer can also be seen. Figure S1c shows a schematic of the film sampler, indicating the location of the UV-transparent cover; the stainless steel sheet as well as both the light-exposed and light-shielded trays. The location of the particle inlet in relation to the sampler is also indicated. S

3 SO PM1 (µg/m (µg/m ) ) RH (%) Radiation (W/m ) Temperature (ºC) a) d) e) b) c) 9/19/1 9/9/1 1/9/1 1/19/1 9/19/1 9/9/1 1/9/1 1/19/1 9/19/1 9/9/1 1/9/1 1/19/1 NO x (µg/m ) 1 f) 9/19/1 9/9/1 1/9/1 1/19/1 NO x NO NO Figure S shows gas phase concentration and meteorological data that were collected over the course of the campaign from the same sampling location as the grime and particles were sampled. S

4 a) Chloride....1 b) Sodium 9/1/1 1/1/1 1/11/1 1/1/1 9/1/1 1/1/1 1/11/1 1/1/ c) Nitrate d) Calcium 9/1/1 1/1/1 1/11/1 1/1/1 9/1/1 1/1/1 1/11/1 1/1/1 s 1 e) Sulfate f) Ammonium 9/1/1 1/1/1 1/11/1 1/1/1 9/1/1 1/1/1 1/11/1 1/1/1 Figure S shows the blank-subtracted mass of ions contained within the film over time, normalized to the geometric surface area of the glass beads. All of the ions show a monotonic increase in concentration over the -week period, with the exception of ammonium, which is below detection limits for most of the campaign. The upper limit ammonium is displayed as the detection limit of ammonium. This uniform growth in ion concentration is consistent with previous studies which showed steady growth in total ion content, even after more than two years of collection. 1 To examine the degree of variability in the data, three samples were collected on October 7; the analysis shows at most a 5 percent difference from the mean value. S

5 Cl - Mass per Volume (µg/m ).1.8. a) Chloride 9/1/1 1/1/1 1/11/1 Na + Mass per Volume (µg/m ) b) Sodium 9/1/1 1/1/1 1/11/1 NO - Mass per Volume (µg/m ) c) Nitrate 9/1/1 1/1/1 1/11/1 Ca + Mass per Volume (µg/m )...1 d) Calcium 9/1/1 1/1/1 1/11/1 SO - Mass per Volume (µg/m ) 1 e) Sulfate 9/1/1 1/1/1 1/11/1 NH + Mass per Volume (µg/m ) f) Ammonium 9/1/1 1/1/1 1/11/1 Figure S shows the mass concentrations of ions within the sampled PM 1. An event showing elevated sodium and chloride is seen at the beginning of the campaign, as discussed in the text. As well, elevated levels of nitrate, sulfate and ammonium were observed for the samples collected from October 1 until October ; this is also reflected in the PM 1 mass loadings displayed in Figure S. The lack of elevated levels of calcium, sodium and chloride during this period suggests the presence of an additional source of fine particulate matter. S5

6 Concentration (ug/m ) a) October to October Concentration (ug/m ) b) October 1 to October Concentration (ug/m ) c) October to October Concentration (ug/m Concentration (ug/m ) ) 5 1 d) October to October d) October to October Concentration (ug/m ) e) October to October Chloride Sulfate Nitrate Sodium Ammonium Calcium Other Figure S5 shows size-resolved particle ion mass concentrations collected daily from October until October 5. Measured values were blank corrected to calculate the values reported herein. As discussed in the methods section, the foils contained a calcium contamination that contributed up to 89% of the measured values. S

7 a) October to October PM b) October 1 to October PM c) October to October PM d) October to October PM e) October to October PM1 Chloride Sulfate Nitrate Sodium Ammonium Calcium Other Figure S show size resolved particle mass normalized to total inorganic ion mass collected daily from October until October 5. For comparison PM1 composition, calculated from the sum of the mass collected from all stages, and final grime composition from October 5 are also displayed. References (1) Favez, O.; Cachier, H.; Chabas, A.; Ausset, P.; Lefevre, R. Atmos Environ,, S7