Isotopic characteristics of precipitation in Slovenia and Croatia: Comparison of continental and maritime stations

Study of the bank filtered groundwater system of the Sava River at Zagreb (Croatia) using isotope analyses

“…The relation of δ 2 H vs. δ 18 O for Zagreb precipitation in 2010 (Fig. 3) is δ 2 H = (7.7 ± 0.3) δ 18 O + (6.1 ± 3.2), n = 12, R = 0.992, and it is in agreement with the long-term Local Meteoric Water Line (LMWL) for Zagreb: δ 2 H = (7.8 ± 0.1) δ 18 O + (5.7 ± 0.8), n = 271, R = 0.98 (Vreća et al 2006). The range of δ 2 H and δ 18 O values (Table 2) …”

Isotopic composition of precipitation in Ljubljana (Slovenia)

“…The observed pattern ( Figure 6) shows generally higher d values in autumn precipitation with means above 10 ‰ and can be attributed to the influence of Mediterranean air masses over the region during this period. Previous investigations showed that Mediterranean air masses probably contribute up to 26% of precipitation in Ljubljana (VRE~A et al, 2006).…”

“…Some previous analyses of isotopic composition of precipitation in Ljubljana have been published by KRAJCAR BRONI} et al (1998), PEZDI~ (1999, 2003, VRE~A et al (2005, 2006, 2007), and OGRINC et al (2008.…”

Isotopic composition of precipitation in Portorož (Slovenia)

“…The natural atmospheric tritium concentration increased about 10 3 times (inGrahaM, 1998) after the nuclear weapon tests in the early 1960s. Since 1963 it has been constantly decreasing, partly due to radioactive decay of tritium and partly due to its redistribution in other water reservoirs, such as the oceans (inGrahaM, 1998;Gat et al, 2001 Broni} et al, 1998;PezDi~, 2003;vre~a et al, 2005, 2006, 2007 and along the River Sava (OGrinc et al, 2008). The data obtained are partly reported to the International Atomic Energy Agency (IAEA) and included in the Global Network of Isotopes in Precipitation (GNIP) and the Global Network of Isotopes in Rivers (GNIR).…”

“…Since the ban of atmospheric nuclear and thermonuclear bomb-tests, the tritium activity in preci pitation showed a basic decreasing trend with a superimposed seasonal structure. However, during the last two decades (approximately), the mean annual values in Zagreb and Ljubljana (krajcar Broni} et al, 1998;vre~a et al, 2006 remai ned stable/constant, at va lues of about 9 TU. The values observed at Portorož are lo wer than for Ljubljana and are typical of stations close to the sea (vre~a et al, 2006, 2008).…”