Assessment of ¹⁴ C and CO ₂ in atmospheric air and pine needles in Gliwice, Poland

Abstract We present a short database of the mole fraction of CO 2 and 14 CO 2 in atmospheric air samples from an urban area in Gliwice, Silesia, Poland. The research covered a period from August 2023 to July 2024. A new laboratory air sampler stand was established to monitor carbon dioxide levels in Gliwice, giving the possibility to determine CO 2 levels in the air using appropriate instruments to collect the air samples, extract CO 2 from them, and thus measure carbon isotopes ratio 14 C/ 12 C. The analysis of the mole fraction of CO 2 was determined using a low-cost system (CARBOCAP GMP343), while the carbon isotopes concentration was measured using MICADAS. The 14 C in the air samples varied randomly from –55 to –24‰, while the monthly mole fraction of CO 2 varied from 428 to 470 ppm. It has been also observed also that CO 2 concentration is linked with the planetary boundary layer. The fraction of fossil of total CO 2 has been estimated at the level of 2.5% during the investigated period of time. Another aim of this study was to investigate pine needles as 14 C archives in a contemporary environment. The examination of the needles was based on the analysis of the similarities and differences in radiocarbon concentrations in pine needles of various ages collected in the middle of consecutive seasons, with 3 months resolution in Gliwice. The concentration of 14 C in the needles was determined using a liquid scintillation counter. The mean F 14 C from all the samples was 99.80(70) pMC.