2021
Bronwyn L. Dunse, Nada Derek, Paul J. Fraser and Paul B. Krummel. Report prepared for the Australian Government Department of Agriculture, Water and the Environment.
Download
About this report
This report has been prepared by the Commonwealth Scientific and Industrial Research Organisation for the Department as a means to provide information to the public and scientific community on global and Australian emissions of ozone depleting substances controlled by the Montreal Protocol on Substances that Deplete the Ozone Layer.
The report summarises atmospheric measurements of ozone depleting substances observed at the Cape Grim facility in Tasmania for the period 1980 to 2020 from the southern hemisphere and from Melbourne. It uses those measurements and established modelling systems to estimate emissions of these ozone depleting substances both globally and from Australia.
The report finds that most of the ozone depleting substances by the Montreal Protocol have declined in concentration in the atmosphere, and that the growth rate of hydro chlorofluorocarbons (HCFCs) has slowed with some HCFCs now decreasing in concentration. An increase in CFC-11 emissions in the period 2013 to 2018 has ceased, with emissions now tracking closer to expected levels. Overall, total chlorine and total bromide decreased in the atmosphere from their peaks 25 years ago. Australian emissions of ozone depleting substances continue to decrease year on year, with most emissions assumed to be from legacy sources.