Current and future levels of mercury atmospheric pollution on a global scale

An assessment of current and future emissions, air concentrations, and atmospheric deposition of mercury worldwide is presented on the basis of results obtained during the performance of the EU GMOS (Global Mercury Observation System) project. Emission estimates for mercury were prepared with the main goal of applying them in models to assess current (2013) and future (2035) air concentrations and atmospheric deposition of this contaminant. The combustion of fossil fuels (mainly coal) for energy and heat production in power plants and in industrial and residential boilers, as well as artisanal and small-scale gold mining, is one of the major anthropogenic sources of Hg emissions to the atmosphere at present. These sources account for about 37 and 25 % of the total anthropogenic Hg emissions globally, estimated to be about 2000 t. Emissions in Asian countries, particularly in China and India, dominate the total emissions of Hg. The current estimates of mercury emissions from natural processes (primary mercury emissions and re-emissions), including mercury depletion events, were estimated to be 5207 t year⁻¹, which represents nearly 70 % of the global mercury emission budget. Oceans are the most important sources (36 %), followed by biomass burning (9 %). A comparison of the 2035 anthropogenic emissions estimated for three different scenarios with current anthropogenic emissions indicates a reduction of these emissions in 2035 up to 85 % for the best-case scenario. <br><br> Two global chemical transport models (GLEMOS and ECHMERIT) have been used for the evaluation of future mercury pollution levels considering future emission scenarios. Projections of future changes in mercury deposition on a global scale simulated by these models for three anthropogenic emissions scenarios of 2035 indicate a decrease in up to 50 % deposition in the Northern Hemisphere and up to 35 % in Southern Hemisphere for the best-case scenario. <br><br> The EU GMOS project has proved to be a very important research instrument for supporting the scientific justification for the Minamata Convention and monitoring of the implementation of targets of this convention, as well as the EU Mercury Strategy. This project provided the state of the art with regard to the development of the latest emission inventories for mercury, future emission scenarios, dispersion modelling of atmospheric mercury on a global and regional scale, and source–receptor techniques for mercury emission apportionment on a global scale

Luftföroreningsepisoden över södra Sverige 2–4 februari 1987

During the period 2-4 February 1987 one of the most severe episodes of polluted air, which has ever been registered in Sweden, occured over southern Sweden.The sulfur dioxide concentrations reached at that time daily mean values around 300 μg m-3 in background as well as in urban areas. The sulfur dioxide concentrations were in urban areas along the Swedish west coast 10- 20 times higher and in background areas 40-50 times higher than the normal mean levels of sulfur dioxide at the corresponding places. Also higher concentrations of nitrogen oxides and soot occured.The meteorological transport calculations show that very large sulfur emissions in Central Europe had contaminated the air that reached southern Sweden during the period 2-4 February. The emissions of sulfur dioxide and soot in Central Europe were extremely large due to the very cold weather. During the period very stable stratification occured in the lower parts of the atmosphere, which caused very limited turbulent dispersion and dilution of the air pollutants. The high concentrations of sulfur dioxide and soot, which occured over southern Sweden , were to a larger part (about 90% or more) caused by the long range transport of air pollutants

Global emission of mercury to the atmosphere from anthropogenic sources in 2005 and projections to 2020

This paper presents the 2005 global inventory of anthropogenic emissions to the atmosphere component of the work that was prepared by UNEP and AMAP as a contribution to the UNEP report Global Atmospheric Mercury Assessment: Sources, Emissions and Transport (UNEP Chemicals Branch, 2008). It describes the methodology applied to compile emissions data on the two main components of the inventory - the 'by-product' emissions and the 'intentional use' emissions - and to geospatially distribute these emissions estimates to produce a gridded dataset for use by modelers, and the results of this work. It also presents some initial results of work to develop (simplified) scenario emissions inventories for 2020 that can be used to investigate the possible implications of actions to reduce mercury emissions at the global scale. (C) 2009 Published by Elsevier Ltd