Assessment of wood burning versus fossil fuel contribution to wintertime black carbon and carbon monoxide concentrations in Athens, Greece

Abstract

Abstract. The scope of this study was to estimate the contribution of fossil fuel and wood burning combustion to black carbon (BC) and carbon monoxide (CO) during wintertime, in Athens. For that purpose, in situ measurements of equivalent black carbon (eBC) and CO were simultaneously conducted in a suburban and an urban background monitoring site in Athens during the 3 months of winter 2014-2015. For the deconvolution of eBC into eBC emitted from fossil fuel (BC ff ) and wood burning (BC wb ), a method based on the spectral dependency of the absorption of pure black carbon and brown carbon was used. Thereafter, BC wb and BC ff estimated fractions were used along with measured CO concentrations in a multiple regression analysis, in order to quantify the contribution of each one of the combustion sources to the ambient CO levels. For a comparative analysis of the results, we additionally estimated the wood burning and fossil fuel contribution to CO, calculated on the basis of their CO / NO x emission ratios. The results indicate that during wintertime BC and CO are mainly emitted by local sources within the Athens Metropolitan Area (AMA). Fossil fuel combustion, mainly from road traffic, is found to be the major contributor to both eBC in PM 2.5 and CO ambient concentrations in AMA. However, wintertime wood burning makes a significant contribution to the observed eBC (of about 30 %) and CO concentrations (on average, 11 and 16 % of total CO in the suburban and urban background sites respectively). Both BC and CO from biomass burning (BC wb and CO wb , respectively) present a clear diurnal pattern, with the highest concentrations during night-time, supporting the theory of local domestic heating being their main source.

Sources and processes that control the submicron organic aerosol composition in an urban Mediterranean environment (Athens): a high temporal-resolution chemical composition measurement study

“…S15-S19 in the Supplement. COA FP exhibits excellent correlation with spectra obtained during previous studies in the city Kostenidou et al, 2015) as well as with spectra obtained in laboratory experiments investigating fresh OA emissions from meat charbroiling (Kaltsonoudis et al, 2017). When calculating the O : C ratio in COA following the study of Canagaratna et al (2015) we find a ratio of 0.19, which is comparable with the value of 0.24 obtained for COA during summer at a suburban site in Athens (Kostenidou et al, 2015).…”

“…S15). COA is excellently correlated with COA from Florou et al (2017) in both Athens and Patras as well as with COA measured by Kaltsonoudis et al (2017) (Fig. S16).…”

“…Conversely, a comparison of the derived SV-OOA with SOA from diesel exhaust after 4 h of photochemical ageing (Sage et al, 2008) yields an r 2 of 0.89. Finally, SV-OOA exhibits the lowest correlations with the mass spectrum from aged OA emissions from meat charbroiling (Kaltsonoudis et al, 2017). The abovementioned comparisons with literature FPs provide some indication that SV-OOA could be linked to SOA formation from the oxidation of volatile organic compounds (VOCs) from both biogenic and traffic sources during summer, and is not linked to the oxidation of primary COA.…”

Multi-year chemical composition of the fine-aerosol fraction in Athens, Greece, with emphasis on the contribution of residential heating in wintertime

“…Previous studies in Athens and the eastern Mediterranean have reached the same conclusion (Siskos et al, 2001;Bardouki et al, 2003;Koulouri et al, 2008). NH + 4 is only significantly correlated to NO − 3 in winter (r = 0.73; p < 0.001), indicative of NH 4 NO 3 formation, as previously suggested for the greater Athens area (GAA) (Karageorgos and Rapsomanikis, 2007;Remoundaki et al, 2013;Paraskevopoulou et al, 2015).…”

“…5) and 44 % during (Fourtziou et al, 2017. Comparably elevated BC wb contributions to BC (29 %-32 %) have been reported for the winter of 2014-2015 at two background locations in the Greater Athens Area (Kalogridis et al, 2018). Similarly, for OC, the PMF-calculated BB contribution of 2.6 µg m −3 to fine OC is comparable to the 2.3 µg m −3 of biomass burning organic aerosol estimated to be present in submicron non-refractory OM in Thissio during the winter of 2013 (Florou et al, 2017).…”