Sources and processes affecting atmospheric sulfur at the onset of Arctic winter
| atmire.migration.oldid | 255 | |
| dc.contributor.advisor | Norman, Ann-Lise | |
| dc.contributor.author | Seguin, Alison Michelle | |
| dc.date.accessioned | 2012-09-13T21:27:11Z | |
| dc.date.available | 2012-11-13T08:01:37Z | |
| dc.date.issued | 2012-09-13 | |
| dc.date.submitted | 2012 | en |
| dc.description.abstract | Arctic size segregated aerosols and SO2 concentrations were measured at two sites at the onset of winter in 2007 and 2008. Concentrations of non sea salt sulfate are within the same range as previous studies in the Arctic. Apportionment with tracer ions and isotopes were used to distinguish between biogenic sulfur and sulfur from other sources including sea salt, anthropogenic and two local Arctic sources; the Smoking Hills and frost flowers. A method to quantitatively differentiate between frost flower and sea salt sulfate using isotope analysis and constrained frost flower ratios is introduced. This is the first time contributions from frost flower in aerosols are reported quantitatively and reached a maximum of 2.3 nmol/m³. Fine aerosol anthropogenic sulfate concentrations were similar between the sites (Alert 0.8 ± 0.6 nmol/m³; Amundsen 0.3 ± 0.4 nmol/m³) and increased with the onset of winter. Ammonium, nitrate and non sea salt potassium correlated with anthropogenic sulfate at both locations. A strong relationship between anthropogenic sulfate and a deficit in aerosol chloride at Alert, Nunavut supports acidification of aerosols from long range transport in the Arctic fall. The first simultaneous measurements of dimethylsulfide (DMS), biogenic SO2, aerosol methanesulfonic acid (MSA) and biogenic sulfate in the Arctic were carried out. Median biogenic SO2 concentration was 0.07 nmol/m³. MSA concentrations decreased with the onset of winter. A median lifetime of 6.1 days for DMS during the sampling period was modeled. Measured MSA branching ratios (median values at Alert = 0.24; Amundsen = 0.28) were compared to ratios predicted by a DMS oxidation model and were found to be similar when modeled halogen and aqueous oxidation was low. DMS oxidation by NO3∙ is expected to be the largest contribution to DMS oxidation in the Arctic fall. A DMS transport model predicts the region around the Amundsen during the campaign was a net source of DMS (median net transport out of the region =10 nmol m-3 day-1) although the area at times acted as a sink. A net source of DMS from Arctic waters supports that sulfur chemistry in the Arctic is representative of regional and not local conditions. | en_US |
| dc.identifier.citation | Seguin, A. M. (2012). Sources and processes affecting atmospheric sulfur at the onset of Arctic winter (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/27834 | en_US |
| dc.identifier.doi | http://dx.doi.org/10.11575/PRISM/27834 | |
| dc.identifier.uri | http://hdl.handle.net/11023/202 | |
| dc.language.iso | eng | |
| dc.publisher.faculty | Graduate Studies | |
| dc.publisher.institution | University of Calgary | en |
| dc.publisher.place | Calgary | en |
| dc.rights | University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission. | |
| dc.subject | Chemistry | |
| dc.subject.classification | Sulfur | en_US |
| dc.subject.classification | atmospheric | en_US |
| dc.subject.classification | isotope | en_US |
| dc.subject.classification | Arctic | en_US |
| dc.subject.classification | sulfate | en_US |
| dc.subject.classification | frost flowers | en_US |
| dc.subject.classification | aerosols | en_US |
| dc.subject.classification | DMS | en_US |
| dc.subject.classification | Alert | en_US |
| dc.subject.classification | SO2 | en_US |
| dc.subject.classification | biogenic | en_US |
| dc.subject.classification | anthropogenic | en_US |
| dc.subject.classification | sea salt | en_US |
| dc.subject.classification | MSA | en_US |
| dc.subject.classification | Oxidation | en_US |
| dc.subject.classification | chloride deficit | en_US |
| dc.subject.classification | transport | en_US |
| dc.subject.classification | Smoking Hills | en_US |
| dc.title | Sources and processes affecting atmospheric sulfur at the onset of Arctic winter | |
| dc.type | doctoral thesis | |
| thesis.degree.discipline | Chemistry | |
| thesis.degree.grantor | University of Calgary | |
| thesis.degree.name | Doctor of Philosophy (PhD) | |
| ucalgary.item.requestcopy | true |