Partitioning of atmospheric carbon dioxide over Central Europe: insights from combined measurements of CO₂mixing ratios and their carbon isotope composition

Abstract

Regular measurements of atmospheric CO (2) mixing ratios and their carbon isotope composition ((13)C/(12)C and (14)C/(12)C ratios) performed between 2005 and 2009 at two sites of contrasting characteristics (Krakow and the remote mountain site Kasprowy Wierch) located in southern Poland were used to derive fossil fuel-related and biogenic contributions to the total CO (2) load measured at both sites. Carbon dioxide present in the atmosphere, not coming from fossil fuel and biogenic sources, was considered 'background' CO (2). In Krakow, the average contribution of fossil fuel CO (2) was approximately 3.4%. The biogenic component was of the same magnitude. Both components revealed a distinct seasonality, with the fossil fuel component reaching maximum values during winter months and the biogenic component shifted in phase by approximately 6 months. The partitioning of the local CO (2) budget for the Kasprowy Wierch site revealed large differences in the derived components: the fossil fuel component was approximately five times lower than that derived for Krakow, whereas the biogenic component was negative in summer, pointing to the importance of photosynthetic sink associated with extensive forests in the neighbourhood of the station. While the presented study has demonstrated the strength of combined measurements of CO (2) mixing ratios and their carbon isotope signature as efficient tools for elucidating the partitioning of local atmospheric CO (2) loads, it also showed the important role of the land cover and the presence of the soil in the footprint of the measurement location, which control the net biogenic surface CO (2) fluxes.

Mixing ratio and carbon isotopic composition investigation of atmospheric CO 2 in Beijing, China

“…In Nagoya, Japan, the CO 2 mixing ratio ranged from 385-470 ppm in May and 385-495 ppm in December from 2008 to 2009 (Wada et al, 2011). In Krakow, Poland, the monthly average value of the CO 2 mixing ratio ranged from 405-425 ppm over the period of January 2005 to December 2009 (Zimnoch et al, 2012).…”

“…In Los Angeles, USA, the δ 13 C value varied from − 9.3 to −7.5‰, −12.5 to −8.8‰, −12.2 to −9.2‰ and −12.5 to −10.2‰ in October, December, February and April samples, respectively (Djuricin et al, 2010). In Krakow, Poland, the δ 13 C value ranged from −11‰ to −9.5‰ (Zimnoch et al, 2012). In Nagoya, Japan, the δ 13 C value ranged from −13.4 to −8.5‰ in May and −15.0 to −8.5‰ in December from 2008 to 2009 (Wada et al, 2011).…”

“…A three-component mixing model was used in Krakow, Poland, and results showed that~90% of the atmospheric CO 2 sources was due to biogenic respiration in summer and that~85% of the atmospheric CO 2 sources was due to anthropogenic emissions in winter (Zimnoch et al, 2004). At Kasprowy Wierch, Poland, anthropogenic emission was approximately 1/5 of that derived for Krakow (Zimnoch et al, 2012). In Paris, France, 14 C and 13 C were used to identify the proportion of fossil fuel combustion and biogenic respiration sources, which were 77% and 23%, respectively, and the contributions from gas and liquid fuel to the fossil fuel combustions were 70% and 30%, respectively (Lopez et al, 2013).…”

“…Measurements of δ 13 C only have been performed at 4 sites: Dallas, Texas, USA (Clark- Thorne and Yapp, 2003); Paris, France (Lopez et al, 2013;Widory and Javoy, 2003); Bangalore City, Karnataka State, India (Guha and Ghosh, 2010); and Wrocław, Poland (Gorka and Lewicka-Szczebak, 2013). Both δ 13 C and δ 18 O observations have been conducted at another 4 sites: Kraków, Poland (Zimnoch et al, 2012, Zimnoch et al, 2004; Bern, Switzerland (Sturm et al, 2006); and Los Angeles Basin, California, USA (Djuricin et al, 2010;Newman et al, 2008). Only 3 urban sites have had long-term continuous observations of the mixing ratio and isotopic composition by IRIS technology.…”

“…δ 13 C S can be used to improve our understanding of potential urban CO 2 sources and underlying mechanisms. Many isotope mixing models based on atmospheric mass conservation have been used to evaluate the contribution of anthropogenic emission (including the combustion of fossil fuels, such as natural gas, gasoline and coal) and biogenic respiration (including plant and soil respiration) components to atmospheric CO 2 (Zimnoch et al, 2012;Djuricin et al, 2010;Pataki et al, 2007;Zimnoch et al, 2004). The development of IRIS technology allows for continuous in situ monitoring of the atmospheric CO 2 mixing ratio, and its δ 13 C and δ 18 O, which can provide additional mechanistic understanding of CO 2 source dynamics over diurnal or even shorter time scales (Wada et al, 2011;Pataki et al, 2006).…”