Atmospheric mercury emissions in Australia from anthropogenic, natural and recycled sources Peter F. Nelson a, * , Anthony L. Morrison a , Hugh J. Malfroy a , Martin Cope b , Sunhee Lee b , Mark L. Hibberd b , C.P. (Mick) Meyer b , John McGregor b a Graduate School of the Environment, Macquarie University, NSW 2109, Australia b Centre for Climate and Weather Research, Private Bag No.1, Aspendale, Vic. 3195, Australia highlights < The first spatially resolved inventory of mercury emissions from Australia. < The best estimate of anthropogenic emissions of mercury in 2006 was 15  5 Mg. < Natural and re-emitted sources comfortably exceed the anthropogenic emission. < Emissions were w8, 140 and 42 Mg pa from vegetation, soils and fires respectively. article info Article history: Received 18 June 2012 Accepted 31 July 2012 Keywords: Mercury Emissions Anthropogenic Natural Inventory abstract The United Nations Environment Programme (UNEP) has begun a process of developing a legally binding instrument to manage emissions of mercury from anthropogenic sources. The UNEP Governing Council has concluded that there is sufficient evidence of significant global adverse impacts from mercury to warrant further international action; and that national, regional and global actions should be initiated as soon as possible to identify populations at risk and to reduce human generated releases. This paper describes the development of, and presents results from, a comprehensive, spatially and temporally resolved inventory of atmospheric mercury emissions from the Australian landmass. Results indicate that the best estimate of total anthropogenic emissions of mercury to the atmosphere in 2006 was 15  5 tonnes. Three industrial sectors contribute substantially to Australian anthropogenic emissions: gold smelting (w50%, essentially from a single site/operation), coal combustion in power plants (w15%) and alumina production from bauxite (w12%). A diverse range of other sectors contribute smaller proportions of the emitted mercury, but industrial emissions account for around 90% of total anthro- pogenic mercury emissions. The other sectors include other industrial sources (mining, smelting, and cement production) and the use of products containing mercury. It is difficult to determine historical trends in mercury emissions given the large uncertainties in the data. Estimates for natural and re- emitted emissions from soil, water, vegetation and fires are made using meteorological models, satel- lite observations of land cover and soil and vegetation type, fuel loading, fire scars and emission factors which account for the effects of temperature, insolation and other environmental variables. These natural and re-emitted sources comfortably exceed the anthropogenic emissions, and comprise 4 e12 tonnes per year from vegetation, 70e210 tonnes per year from soils, and 21e63 tonnes per year from fires. Ó 2012 Elsevier Ltd. All rights reserved. 1. Introduction Mercury is a naturally occurring metal found in small quantities throughout the environment in both the atmosphere and in aquatic and terrestrial ecosystems. While it is continuously released, transported, transformed and stored in and between these compartments, the atmosphere is considered to be the dominant transport medium of mercury in the environment (Fitzgerald et al., 1991; Lindquist et al., 1991; Pirrone and Mahaffey, 2005; Pirrone and Mason, 2008). Previous monitoring and modelling studies, and a number of reviews which have summarised published data concerning the * Corresponding author. E-mail addresses: pnelson@gse.mq.edu.au, peter.nelson@mq.edu.au (P.F. Nelson). Contents lists available at SciVerse ScienceDirect Atmospheric Environment journal homepage: www.elsevier.com/locate/atmosenv 1352-2310/$ e see front matter Ó 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.atmosenv.2012.07.067 Atmospheric Environment 62 (2012) 291e302