The measurement of radioactive noble gases by DWD in the frame of the Global Atmospheric Watch programme of WMO

The Deutscher Wetterdienst (DWD, German Meteorological Service) is integrated into the Global Atmospheric Watch programme (GAW) of the World Meteorological Organization (WMO). According to this programme a variety of chemical compounds and radionuclides are measured at global stations. At the research platform "Schneefernerhaus" Be-7. Rn-222, and its decay products, C-14 in CO2, tritium as HTO, Kr-85 and Xe-133 are continuously monitored by the DWD or are sampled and then measured at the central laboratory in Offenbach. The results are used as additional information for studying atmospheric mixing processes or on the other hand as information about the background level of radioactivity. As a main subject of this paper the integration and partly the optimization of sampling and measuring procedures for the detection of noble gases are described. In particular, the methods of quality assurance are discussed for Kr and Xe. (C) 2004 Elsevier Ltd. All rights reserved.