title: Describing the annual cyclic behaviour of 7Be concentrations in surface air in Oceania.
abstract: Surface air concentrations of 7Be at a number of stations in Oceania show a distinct annual cycle. We apply a sinusoidal model to describe this cycle. The results show that peak 7Be concentrations in surface air occur during early spring at tropical latitudes and during mid-to-late summer at middle latitudes. Comparison with available 90Sr surface air data for the southern hemisphere indicates that stratosphere-to-troposphere exchange is an active atmospheric process controlling the 7Be annual cycle throughout the Oceania region. Vertical transport of air within the troposphere also seems to influence the observed annual cycle. Seasonality in rainfall is not thought to control the annual cyclic behaviour of 7Be in surface air.
authors: Radiological Laboratory, School of Physical and Chemical Sciences, Queensland University of Technology, 2 George Street, Brisbane, Qld. 4000, Australia.
authors: Che
authors: C
authors: Doering
authors: Riaz
authors: R
authors: Akber
mesh_terms: D000396:Air Pollutants, Radioactive / Q000032:analysis*; D001608:Beryllium / Q000032:analysis*; D005843:Geography; D044349:Oceania; D011834:Radiation Monitoring / Q000379:methods; D011868:Radioisotopes / Q000032:analysis*; D012621:Seasons
chemical_list: D000396:Air Pollutants, Radioactive; D011868:Radioisotopes; D001608:Beryllium