Stable isotope composition of daily and monthly precipitation in Zagreb

Stable isotopic compositions (delta H-2 and delta O-18) of daily precipitation collected in the period from October 2002 to March 2003 and monthly precipitation in the period from 2001 to 2003, as well as the corresponding meteorological data (temperature, amount of precipitation), all collected in Zagreb, Croatia, are presented. delta H-2 and delta O-18 values, both daily and monthly, show large variations due to large temperature variations and the different origin of the air masses. Variations are larger for daily samples than for composite monthly samples. Good correlation of delta O-18 with temperature is obtained for both types of samples. On the basis of the correlation between delta H-2 and delta O-18, the local meteoric water line is close to the global meteoric water line. Deuterium excess of both daily and monthly precipitation indicates that in the Zagreb area, the influence of air masses from the Mediterranean area prevails in the autumn period.