Long-time atmospheric 3H and 14C record in Croatia

The natural production of radioisotopes 14C and 3H in the atmosphere is in an equilibrium with their radioactive decay and their world-wide distribution has attained a steady state with subtle variations depending on the latitude, season and solar modulation. This steady state, however, was disturbed significantly during sixties, when the natural activities of 14C and 3H increased due to extensive nuclear bomb tests. 14C and 3H distribution in the atmosphere started to be monitored about at the same time, therefore, the peaks due to the anthropogenically produced 14C and 3H were recorded. Since then, atmospheric 14C and 3H activities are regularly measured as a part of a network or local monitoring. In this paper we present the complete record of 14C and 3H data measured in Zagreb. We present an attempt of analytical representation of our data, and we compare our data with recently published 14C records in Europe and in Canada, as well as with the tritium data in precipitation published by IAEA. (author)