ANSTO radon monitoring within the WMO global atmosphere watch programme

Abstract

A brief overview of results from the ANSTO radon programmes at the Cape Grim (Tasmania) and Mauna Loa Observatory (Hawaii), World Meteorological Organisation Global Atmosphere Watch stations it presented. At Cape Grim, a 100 mBq m3 threshold on radon concentration observations has proven to be a suitable criterion for Baseline monitoring. Furthermore, analysis of the Cape Grim Baseline radon data has enabled the characterisation of the oceanic radon flux over the Southern Ocean Cape Grim fetch region. Radon observations at the Mauna Loa Observatory, in conjunction with back trajectory analysis, have helped to identify the source regions of the most pervasive pollution events in the atmosphere of the Pacific Basin. The seasonal variability in the strength of terrestrial influence on Pacific air masses has also been characterised.