Daily precipitation was collected in the period from May to December 2010, along with the corresponding meteorological data (air temperature, humidity, amount of precipitation) in the Vinca Institute of Nuclear Sciences (44°45'33'' N, 20°35'57'' E), Belgrade, Serbia. On the basis of backward trajectory analysis, three dominant trajectory categories are determined: southwestern Europe (SW), northeastern Europe (NE), and northwestern Europe (NW), which were associated with 49 (71%) of the events. The highest daily δ 18 O and δ 2 H values were measured on 9 December (–1.3‰ and –8.7‰, respectively), whereas the lowest values were measured on 28 December (–143.2‰ and –19.3‰, respectively). Circulation back trajectories, synoptic-scale surface and middle-tropospheric weather maps, and δ 2 H and δ 18 O values for 69 precipitation samples, were examined to determine the origin and direction of the air masses for each event. Keywords: daily precipitation, Belgrade, stable isotope content Introduction Factors that control stable isotopic compositions (δ 2 H and δ 18 O) of precipitation involve fractionation processes associated with the evaporation and condensation history of the precipitating water vapor. These factors include the temperature, the amount of precipitation, the isotope value of the water vapor Addresses: N. Miljevic ´, A. Pešic ´: Jaroslava Cernog 80, 11226 Belgrade, Serbia, e-mail: emiljevi@vinca.rs D. Goloboc `´anin: POB 522, 11001 Belgrade, Serbia, e-mail: golddus@gmail.com Z. Gršic ´: Mike Petrovica Alasa 12-14, 11351 Belgrade, Serbia, e-mail: grsa@vinca.rs M. Unkaševic ´, I. Tošic ´: POB 368, 11000 Belgrade, Serbia, e-mails: miroslava@ff.bg.ac.rs, itosic@ff.bg.ac.rs Received: May 14, 2011; accepted: May 26, 2011 1788-2281/$ 20.00 © 2010 Akadémiai Kiadó, Budapest Central European Geology, Vol. 53/4, pp. 419–422 (2010) DOI: 10.1556/CEuGeol.53.2010.4.5 Relationship between atmospheric circulation and stable isotope composition of Belgrade daily precipitation Nada Miljevic ´, Ana Pešic ´ Dušan Goloboc `´anin Jaroslav Cerni Institute Vinca Institute for Nuclear Sciences, Belgrade for Development of Water Resources, Belgrade Zoran Gršic ´ Miroslava Unkaševic ´, Ivana Tošic ´ Nuclear Facilities of Serbia, Belgrade Institute of Meteorology, Faculty of Physics, University of Belgrade, Belgrade