Abstract. The results of regular observations of atmospheric CO2 mixing ratios and its carbon isotope composition (δ13C, Δ14C), carried out at two continental sites located in central Europe are presented and discussed. The sites (Kasprowy Wierch, 49°14' N, 19°59' E, 1989 m a.s.l.; Krakow, 50°04' N, 19°55' E, 220 m a.s.l.), are located in two contrasting environments: (i) high-altitude mountaneous area, relatively free of anthropogenic influences, and (ii) typical urban environment with numerous local sources of carbon dioxide. Despite of relative proximity of those sites (ca. 100 km), substantial differences in both the recorded CO2 levels and their isotopic composition were detected. The CO2 mixing ratios measured in the urban atmosphere revealed quasi-permanent excess concentration of this gas when compared with near-by background atmosphere. The annual mean CO2 concentration recorded in Krakow in 2004 was almost 10% higher than that recorded at high-altitude mountain site (Kasprowy Wierch). Such effect is occuring probably in all urban centers. Carbon isotopic composition of atmospheric CO2 proved to be efficient tool for identification the surface CO2 fluxes into the atmosphere related to fossil fuel burning and their influence on the recorded levels of this gas in the local atmosphere. The available records of Δ14C for Krakow and Kasprowy Wierch suggest gradual reduction of 14C-free CO2 fluxes into the urban atmosphere of Krakow in the past several years.
Changes in temperature and oxygen isotopic composition of Mediterranean water during the Mid-Pleistocene transition in the Montalbano Jonico section (southern Italy) using the clumped-isotope thermometer