AAAR 34th Annual Conference
October 12 - October 16, 2015
Hyatt Regency
Minneapolis, Minnesota, USA
Abstract View
Spatial Distribution, Chemical Composition, and Sources of Atmospheric Gases and Aerosols in Estonia
MIRIAM ELSER, Carlo Bozzetti, Imad El Haddad, Rene Richter, Marek Maasikmets, Erik Teinemaa, Urs Baltensperger, Andre Prévôt, Paul Scherrer Institute
Abstract Number: 209 Working Group: Urban Aerosols
Abstract The spatial distribution, chemical composition and sources of infectious and climate relevant gases and aerosols were examined during March 2014 at three contrasted sites in Estonia (Tartu, Kohtla- Järve/Kiviõli and Tallinn), using a mobile platform. This constitutes to the best of our knowledge the first detailed in-situ measurements in the Baltic region, whose air-quality remains poorly characterized. The chemical composition of the non-refractory aerosols in the PM2.5 fraction was measured with a High Resolution Time of Flight Aerosol Mass Spectrometer, equipped with a newly developed high pressure lens. A 7-wavelength Aethalometer was used to monitor equivalent black carbon concentrations and a condensation particle counter to measure particle number concentrations. The concentrations of trace gases, including ammonia, carbon monoxide, carbon dioxide and methane were also measured. All measurements were performed with high time resolution (seconds), critical for the identification of source regions using a mobile platform.
The average measured concentrations in both particle and gas phase are overall relatively low, but stagnant conditions, which occur frequently, induce the accumulation of locally emitted primary aerosols. In Tartu and Tallinn (the two major cities in Estonia) organics and black carbon dominate the particle-phase composition. The contribution of primary sources to organic matter strongly depends on the sampling location, with wood burning dominating in residential areas, whereas the contribution of oxygenated organic aerosols is spatially homogeneous. Urban increments of the different pollutants have been assessed by combining measurements outside and inside these cities. In Kohtla-Järve and Kiviõli sulfate is dominant, mostly produced from the two shale-oil factories present in the area. The contribution of different industrial processes, including shale oil and energy production could be assessed using factor analysis.