References

ACP

Atmospheric Chemistry and Physics

ACP

Atmos. Chem. Phys.

1680-7324

Copernicus Publications

Göttingen, Germany

10.5194/acp-12-8993-2012

Estimation of mercury emissions from forest fires, lakes, regional and local sources using measurements in Milwaukee and an inverse method

de Foy

¹ Wiedinmyer

² Schauer

J. J.

Department of Earth and Atmospheric Sciences, Saint Louis University, MO, USA

National Center of Atmospheric Research, Boulder, CO, USA

Civil and Environmental Engineering, University of Wisconsin – Madison, WI, USA

02 10 2012

12 19 8993 9011

2012

This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/

This article is available from https://acp.copernicus.org/articles/12/8993/2012/acp-12-8993-2012.html

The full text article is available as a PDF file from https://acp.copernicus.org/articles/12/8993/2012/acp-12-8993-2012.pdf

Gaseous elemental mercury is a global pollutant that can lead to serious health concerns via deposition to the biosphere and bio-accumulation in the food chain. Hourly measurements between June 2004 and May 2005 in an urban site (Milwaukee, WI) show elevated levels of mercury in the atmosphere with numerous short-lived peaks as well as longer-lived episodes. The measurements are analyzed with an inverse model to obtain information about mercury emissions. The model is based on high resolution meteorological simulations (WRF), hourly back-trajectories (WRF-FLEXPART) and a chemical transport model (CAMx). The hybrid formulation combining back-trajectories and Eulerian simulations is used to identify potential source regions as well as the impacts of forest fires and lake surface emissions. Uncertainty bounds are estimated using a bootstrap method on the inversions. Comparison with the US Environmental Protection Agency's National Emission Inventory (NEI) and Toxic Release Inventory (TRI) shows that emissions from coal-fired power plants are properly characterized, but emissions from local urban sources, waste incineration and metal processing could be significantly under-estimated. Emissions from the lake surface and from forest fires were found to have significant impacts on mercury levels in Milwaukee, and to be underestimated by a factor of two or more.

References 1

Akagi, S. K., Yokelson, R. J., Wiedinmyer, C., Alvarado, M. J., Reid, J. S., Karl, T., Crounse, J. D., and Wennberg, P. O.: Emission factors for open and domestic biomass burning for use in atmospheric models, Atmos. Chem. Phys., 11, 4039–4072, <a href="http://dx.doi.org/10.5194/acp-11-4039-2011">https://doi.org/10.5194/acp-11-4039-2011</a>, 2011.

Ashbaugh, L. L., Malm, W. C., and Sadeh, W. Z.: A residence time probability analysis of sulfur concentrations at grand-canyon-national-park, Atmos. Environ., 19, 1263–1270, 1985.

Aster, R. C., Borchers, B., and Turber, C. H.: Parameter Estimation and Inverse Problems, Academic Press, second edn., 2012.

Bagnato, E., Aiuppa, A., Parello, F., Allard, P., Shinohara, H., Liuzzo, M., and Giudice, G.: New clues on the contribution of Earth's volcanism to the global mercury cycle, Bull. Volcan., 73, 497–510, <a href="http://dx.doi.org/10.1007/s00445-010-0419-y">https://doi.org/10.1007/s00445-010-0419-y</a>, 2011.

Bash, J., Miller, D., Meyer, T., and Bresnahan, P.: Northeast United States and Southeast Canada natural mercury emissions estimated with a surface emission model, Atmos. Environ., 38, 5683–5692, <a href="http://dx.doi.org/10.1016/j.atmosenv.2004.05.058">https://doi.org/10.1016/j.atmosenv.2004.05.058</a>, 2004.

Bash, J. O.: Description and initial simulation of a dynamic bidirectional air-surface exchange model for mercury in Community Multiscale Air Quality (CMAQ) model, J. Geophys. Res.-Atmos., 115, <a href="http://dx.doi.org/10.1029/2009JD012834">https://doi.org/10.1029/2009JD012834</a>, 2010.

Bash, J. O. and Miller, D. R.: A relaxed eddy accumulation system for measuring surface fluxes of total gaseous mercury, J. Atmos. Ocean. Technol., 25, 244–257, <a href="http://dx.doi.org/10.1175/2007JTECHA908.1">https://doi.org/10.1175/2007JTECHA908.1</a>, 2008.

Brioude, J., Kim, S.-W., Angevine, W. M., Frost, G. J., Lee, S.-H., McKeen, S. A., Trainer, M., Fehsenfeld, F. C., Holloway, J. S., Ryerson, T. B., Williams, E. J., Petron, G., and Fast, J. D.: Top-down estimate of anthropogenic emission inventories and their interannual variability in Houston using a mesoscale inverse modeling technique, J. Geophys. Res.-Atmos., 116, D20305, <a href="http://dx.doi.org/10.1029/2011JD016215">https://doi.org/10.1029/2011JD016215</a>, 2011.

Bullock, Jr., O. R., Atkinson, D., Braverman, T., Civerolo, K., Dastoor, A., Davignon, D., Ku, J.-Y., Lohman, K., Myers, T. C., Park, R. J., Seigneur, C., Selin, N. E., Sistla, G., and Vijayaraghavan, K.: The North American Mercury Model Intercomparison Study (NAMMIS): Study description and model-to-model comparisons, J. Geophys. Res.-Atmos., 113, D17310, <a href="http://dx.doi.org/10.1029/2008JD009803">https://doi.org/10.1029/2008JD009803</a>, 2008.

Carroll, M., Townshend, J., Hansen, M., DiMiceli, C., Sohlberg, R., and Wurster, K.: Vegetative Cover Conversion and Vegetation Continuous Fields, in: Land Remote Sensing and Global Environmental Change: NASA's Earth Observing System and the Science of Aster and MODIS, edited by: Ramachandran, B., Justice, C. O., and Abrams, M., Springer-Verlag, <a href="http://dx.doi.org/10.1007/978-1-4419-6749-7">https://doi.org/10.1007/978-1-4419-6749-7</a>, 2011.

Cheng, I., Lu, J., and Song, X.: Studies of potential sources that contributed to atmospheric mercury in Toronto, Canada, Atmos. Environ., 43, 6145–6158, <a href="http://dx.doi.org/10.1016/j.atmosenv.2009.09.008">https://doi.org/10.1016/j.atmosenv.2009.09.008</a>, 2009.

Cheng, I., Zhang, L., Blanchard, P., Graydon, J. A., and Louis, V. L. S.: Source-receptor relationships for speciated atmospheric mercury at the remote Experimental Lakes Area, northwestern Ontario, Canada, Atmos. Chem. Phys., 12, 1903–1922, <a href="http://dx.doi.org/10.5194/acp-12-1903-2012">https://doi.org/10.5194/acp-12-1903-2012</a>, 2012.

Ci, Z., Zhang, X., and Wang, Z.: Elemental mercury in coastal seawater of Yellow Sea, China: Temporal variation and air-sea exchange, Atmos. Environ., 45, 183–190, <a href="http://dx.doi.org/10.1016/j.atmosenv.2010.09.025">https://doi.org/10.1016/j.atmosenv.2010.09.025</a>, 2011}{a.

Ci, Z. J., Zhang, X. S., Wang, Z. W., Niu, Z. C., Diao, X. Y., and Wang, S. W.: Distribution and air-sea exchange of mercury (Hg) in the Yellow Sea, Atmos. Chem. Phys., 11, 2881–2892, <a href="http://dx.doi.org/10.5194/acp-11-2881-2011">https://doi.org/10.5194/acp-11-2881-2011</a>, 2011}{b.

Cohen, M., Artz, R., Draxler, R., Miller, P., Poissant, L., Niemi, D., Ratte, D., Deslauriers, M., Duval, R., Laurin, R., Slotnick, J., Nettesheim, T., and McDonald, J.: Modeling the atmospheric transport and deposition of mercury to the Great Lakes, Environ. Res., 95, 247–265, <a href="http://dx.doi.org/10.1016/j.envres.2003.11.007">https://doi.org/10.1016/j.envres.2003.11.007</a>, 2004.

de Foy, B., Lei, W., Zavala, M., Volkamer, R., Samuelsson, J., Mellqvist, J., Galle, B., Martinez, A. P., Grutter, M., Retama, A., and Molina, L. T.: Modelling constraints on the emission inventory and on vertical dispersion for CO and SO2 in the Mexico City} Metropolitan {Area} using Solar {FTIR} and zenith sky UV spectroscopy, Atmos. Chem. Phys., 7, 781–801, doi{10.5194/acp-7-781-2007, 2007.

de Foy, B., Zavala, M., Bei, N., and Molina, L. T.: Evaluation of WRF mesoscale simulations and particle trajectory analysis for the MILAGRO field campaign, Atmos. Chem. Phys., 9, 4419–4438, doi{10.5194/acp-9-4419-2009}, 2009.

de Foy, B., Smyth, A. M., Thompson, S. L., Gross, D. S., Olson, M. R., Sager, N., and Schauer, J. J.: Sources of Nickel, Vanadium and Black Carbon in Aerosols in Milwaukee, Atmos. Environ., 59, 294–301, <a href="http://dx.doi.org/10.1016/j.atmosenv.2012.06.002">https://doi.org/10.1016/j.atmosenv.2012.06.002</a>, 2012.

Doran, J. C., Fast, J. D., Barnard, J. C., Laskin, A., Desyaterik, Y., and Gilles, M. K.: Applications of Lagrangian dispersion modeling to the analysis of changes in the specific absorption of elemental carbon, Atmos. Chem. Phys., 8, 1377–1389, doi{10.5194/acp-8-1377-2008}, 2008.

Eckhardt, S., Prata, A. J., Seibert, P., Stebel, K., and Stohl, A.: Estimation of the vertical profile of sulfur dioxide injection into the atmosphere by a volcanic eruption using satellite column measurements and inverse transport modeling, Atmos. Chem. Phys., 8, 3881–3897, doi{10.5194/acp-8-3881-2008}, 2008.

Engle, M. A., Tate, M. T., Krabbenhoft, D. P., Schauer, J. J., Kolker, A., Shanley, J. B., and Bothner, M. H.: Comparison of atmospheric mercury speciation and deposition at nine sites across central and eastern North America, J. Geophys. Res.-Atmos., 115, D18306, <a href="http://dx.doi.org/10.1029/2010JD014064">https://doi.org/10.1029/2010JD014064</a>, 2010.

Enting, I. G.: Inverse Problems in Atmospheric Constituent Transport, Cambridge University Press, UK, p. 51, 2002.

ENVIRON: CAMx, comprehensive air quality model with extensions, User's Guide, Tech. Rep. Version 5.40, ENVIRON International Corporation, 2011.

Fast, J. D. and Easter, R.: A Lagrangian Particle Dispersion Model Compatible with WRF, in: 7th WRF User's Workshop, Boulder, CO, USA, 2006.

Friedl, M. A., Sulla-Menashe, D., Tan, B., Schneider, A., Ramankutty, N., Sibley, A., and Huang, X.: MODIS Collection 5 global land cover: Algorithm refinements and characterization of new datasets, Remote Sens. Environ., 114, 168–182, <a href="http://dx.doi.org/10.1016/j.rse.2009.08.016">https://doi.org/10.1016/j.rse.2009.08.016</a>, 2010.

Gbor, P., Wen, D., Meng, F., Yang, F., Zhang, B., and Sloan, J.: Improved model for mercury emission, transport and deposition, Atmos. Environ., 40, 973–983, <a href="http://dx.doi.org/10.1016/j.atmosenv.2005.10.040">https://doi.org/10.1016/j.atmosenv.2005.10.040</a>, 2006.

Gbor, P. K., Wen, D., Meng, F., Yang, F., and Sloan, J. J.: Modeling of mercury emission, transport and deposition in North America, Atmos. Environ., 41, 1135–1149, <a href="http://dx.doi.org/10.1016/j.atmosenv.2006.10.005">https://doi.org/10.1016/j.atmosenv.2006.10.005</a>, 2007.

Giglio, L., Descloitres, J., Justice, C., and Kaufman, Y.: An enhanced contextual fire detection algorithm for MODIS, Remote Sens. Environ., 87, 273–282, <a href="http://dx.doi.org/10.1016/S0034-4257(03)00184-6">https://doi.org/10.1016/S0034-4257(03)00184-6</a>, 2003.

Han, Y., Holsen, T., Hopke, P., and Yi, S.: Comparison between back-trajectory based modeling and Lagrangian backward dispersion Modeling for locating sources of reactive gaseous mercury, Environ. Sci. Technol., 39, 1715–1723, <a href="http://dx.doi.org/10.1021/es0498540">https://doi.org/10.1021/es0498540</a>, 2005.

Han, Y.-J., Holsen, T. M., and Hopke, P. K.: Estimation of source locations of total gaseous mercury measured in New York State using trajectory-based models, Atmos. Environ., 41, 6033–6047, <a href="http://dx.doi.org/10.1016/j.atmosenv.2007.03.027">https://doi.org/10.1016/j.atmosenv.2007.03.027</a>, 2007.

Hansen, M., Townshend, J., Defries, R., and Carroll, M.: Estimation of tree cover using MODIS data at global, continental and regional/local scales, Int. J. Remote Sens., 26, 4359–4380, 2005.

Hansen, M. C., DeFries, R. S., Townshend, J. R. G., Carroll, M., Dimiceli, C., and Sohlberg, R. A.: Global Percent Tree Cover at a Spatial Resolution of 500 Meters: First Results of the MODIS Vegetation Continuous Fields Algorithm, Earth Interact., 7, 1–15, 2003.

Hansen, P. C.: Discrete Inverse Problems: Insight and Algorithms, SIAM – Soc. Industr. Appl. Math., 53–105, 2010.

Henze, D. K., Seinfeld, J. H., and Shindell, D. T.: Inverse modeling and mapping US air quality influences of inorganic PM(2.5) precursor emissions using the adjoint of GEOS-Chem, Atmos. Chem. Phys., 9, 5877–5903, doi{10.5194/acp-9-5877-2009}, 2009.

Hoelzemann, J., Schultz, M., Brasseur, G., Granier, C., and Simon, M.: Global Wildland Fire Emission Model (GWEM): Evaluating the use of global area burnt satellite data, J. Geophys. Res.-Atmos., 109, D14S04, <a href="http://dx.doi.org/10.1029/2003JD003666">https://doi.org/10.1029/2003JD003666</a>, 2004.

Hogrefe, C., Rao, S., Kasibhatla, P., Hao, W., Sistla, G., Mathur, R., and McHenry, J.: Evaluating the performance of regional-scale photochemical modeling systems: Part II - ozone predictions, Atmos. Environ., 35, 4175–4188, <a href="http://dx.doi.org/10.1016/S1352-2310(01)00183-2">https://doi.org/10.1016/S1352-2310(01)00183-2</a>, 2001.

Hogrefe, C., Vempaty, S., Rao, S., and Porter, P.: A comparison of four techniques for separating different time scales in atmospheric variables, Atmos. Environ., 37, 313–325, <a href="http://dx.doi.org/10.1016/S1352-2310(02)00897-X">https://doi.org/10.1016/S1352-2310(02)00897-X</a>, 2003.

Hong, S. Y., Noh, Y., and Dudhia, J.: A new vertical diffusion package with an explicit treatment of entrainment processes, Mon. Weather Rev., 134, 2318–2341, 2006.

Huang, J., Choi, H.-D., Hopke, P. K., and Holsen, T. M.: Ambient Mercury Sources in Rochester, NY: Results from Principle Components Analysis (PCA) of Mercury Monitoring Network Data, Environ. Sci. Technol., 44, 8441–8445, <a href="http://dx.doi.org/10.1021/es102744j">https://doi.org/10.1021/es102744j</a>, 2010.

Kain, J. S.: The Kain-Fritsch convective parameterization: An update, J. Appl. Meteorol., 43, 170–181, 2004.

Kolker, A., Olson, M. L., Krabbenhoft, D. P., Tate, M. T., and Engle, M. A.: Patterns of mercury dispersion from local and regional emission sources, rural Central Wisconsin, USA, Atmos. Chem. Phys., 10, 4467–4476, <a href="http://dx.doi.org/10.5194/acp-10-4467-2010">https://doi.org/10.5194/acp-10-4467-2010</a>, 2010.

Kuss, J., Holzmann, J., and Ludwig, R.: An Elemental Mercury Diffusion Coefficient for Natural Waters Determined by Molecular Dynamics Simulation, Environ. Sci. Technol., 43, 3183–3186, <a href="http://dx.doi.org/10.1021/es8034889">https://doi.org/10.1021/es8034889</a>, 2009.

Lai, S.-O., Holsen, T. M., Han, Y.-J., Hopke, P. P., Yi, S.-M., Blanchard, P., Pagano, J. J., and Milligan, M.: Estimation of mercury loadings to Lake Ontario: Results from the Lake Ontario atmospheric deposition study (LOADS), Atmos. Environ., 41, 8205–8218, <a href="http://dx.doi.org/10.1016/j.atmosenv.2007.06.035">https://doi.org/10.1016/j.atmosenv.2007.06.035</a>, 2007.

Lauvaux, T., Uliasz, M., Sarrat, C., Chevallier, F., Bousquet, P., Lac, C., Davis, K. J., Ciais, P., Denning, A. S., and Rayner, P. J.: Mesoscale inversion: first results from the CERES campaign with synthetic data, Atmos. Chem. Phys., 8, 3459–3471, doi{10.5194/acp-8-3459-2008}, 2008.

Lin, C., Lindberg, S., Ho, T., and Jang, C.: Development of a processor in BEIS3 for estimating vegetative mercury emission in the continental United States, Atmos. Environ., 39, 7529–7540, <a href="http://dx.doi.org/10.1016/j.atmosenv.2005.04.044">https://doi.org/10.1016/j.atmosenv.2005.04.044</a>, 7th International Conference on Mercury as a Global Pollutant, Ljubljana, SLOVENIA, 28 June–2 July 2004, 2005.

Lin, X. and Tao, Y.: A numerical modelling study on regional mercury budget for eastern North America, Atmos. Chem. Phys., 3, 535–548, doi{10.5194/acp-3-535-2003}, 2003.

Lindberg, S., Bullock, R., Ebinghaus, R., Engstrom, D., Feng, X., Fitzgerald, W., Pirrone, N., Prestbo, E., and Seigneur, C.: A synthesis of progress and uncertainties in attributing the sources of mercury in deposition, Ambio, 36, 19–32, 8th International Conference on Mercury as a Global Pollutant, Madison, WI, AUG 06-11, 2006, 2007.

Liu, B., Keeler, G. J., Dvonch, J. T., Barres, J. A., Lynam, M. M., Marsik, F. J., and Morgan, J. T.: Urban-rural differences in atmospheric mercury speciation, Atmos. Environ., 44, 2013–2023, <a href="http://dx.doi.org/10.1016/j.atmosenv.2010.02.012">https://doi.org/10.1016/j.atmosenv.2010.02.012</a>, 2010.

Lorenc, A. C.: Analysis Methods for Numerical Weather Prediction, Q. J. R. Meteorol. Soc., 112, 1177–1194, 1986.

Manning, A. J.: The challenge of estimating regional trace gas emissions from atmospheric observations, Phil. Trans. Roy. Soc. A – Math. Phys. Eng. Sci., 369, 1943–1954, <a href="http://dx.doi.org/10.1098/rsta.2010.0321">https://doi.org/10.1098/rsta.2010.0321</a>, 2011.

Manning, A. J., O'Doherty, S., Jones, A. R., Simmonds, P. G., and Derwent, R. G.: Estimating UK methane and nitrous oxide emissions from 1990 to 2007 using an inversion modeling approach, J. Geophys. Res.-Atmos., 116, D02305, <a href="http://dx.doi.org/10.1029/2010JD014763">https://doi.org/10.1029/2010JD014763</a>, 2011.

Manolopoulos, H., Schauer, J. J., Purcell, M. D., Rudolph, T. M., Olson, M. L., Rodger, B., and Krabbenhoft, D. P.: Local and regional factors affecting atmospheric mercury speciation at a remote location, J. Environ. Eng. Sci., 6, 491–501, <a href="http://dx.doi.org/10.1139/S07-005">https://doi.org/10.1139/S07-005</a>, 2007}{a.

Manolopoulos, H., Snyder, D. C., Schauer, J. J., Hill, J. S., Turner, J. R., Olson, M. L., and Krabbenhoft, D. P.: Sources of speciated atmospheric mercury at a residential neighborhood impacted by industrial sources, Environ. Sci. Technol., 41, 5626–5633, <a href="http://dx.doi.org/10.1021/es0700348">https://doi.org/10.1021/es0700348</a>, 2007}{b.

Mergler, D., Anderson, H. A., Chan, L. H. M., Mahaffey, K. R., Murray, M., Sakamoto, M., and Stern, A. H.: Methylmercury exposure and health effects in humans: A worldwide concern, Ambio, 36, 3–11, 8th International Conference on Mercury as a Global Pollutant, Madison, WI, 6–11 August 2006, 2007.

Mesinger, F., DiMego, G., Kalnay, E., Mitchell, K., Shafran, P., Ebisuzaki, W., Jovic, D., Woollen, J., Rogers, E., Berbery, E., Ek, M., Fan, Y., Grumbine, R., Higgins, W., Li, H., Lin, Y., Manikin, G., Parrish, D., and Shi, W.: North American regional reanalysis, B. Am. Meteorol. Soc., 87, 343–360, <a href="http://dx.doi.org/10.1175/BAMS-87-3-343">https://doi.org/10.1175/BAMS-87-3-343</a>, 2006.

Murray, M. and Holmes, S.: Assessment of mercury emissions inventories for the Great Lakes states, Environ. Res., 95, 282–297, <a href="http://dx.doi.org/10.1016/j.envres.2004.02.007">https://doi.org/10.1016/j.envres.2004.02.007</a>, Workshop on an Ecosystem Approach to the Health Effects of Mercury in the Great Lakes Basin, Windsor, Canada, 26–27 Feburary 2003, 2004.

O'Brien, J. J.: A note on the vertical structure of the eddy exchange coefficient in the planetary boundary layer, J. Atmos. Sci., 27, 1214–1215, 1970.

Pirrone, N., Cinnirella, S., Feng, X., Finkelman, R. B., Friedli, H. R., Leaner, J., Mason, R., Mukherjee, A. B., Stracher, G. B., Streets, D. G., and Telmer, K.: Global mercury emissions to the atmosphere from anthropogenic and natural sources, Atmos. Chem. Phys., 10, 5951–5964, <a href="http://dx.doi.org/10.5194/acp-10-5951-2010">https://doi.org/10.5194/acp-10-5951-2010</a>, 2010.

Poissant, L., Amyot, M., Pilote, M., and Lean, D.: Mercury water-air exchange over the Upper St. Lawrence River and Lake Ontario, Environ. Sci. Technol., 34, 3069–3078, <a href="http://dx.doi.org/10.1021/es990719a">https://doi.org/10.1021/es990719a</a>, 2000.

Rigby, M., Manning, A. J., and Prinn, R. G.: Inversion of long-lived trace gas emissions using combined Eulerian and Lagrangian chemical transport models, Atmos. Chem. Phys., 11, 9887–9898, <a href="http://dx.doi.org/10.5194/acp-11-9887-2011">https://doi.org/10.5194/acp-11-9887-2011</a>, 2011.

Roedenbeck, C., Gerbig, C., Trusilova, K., and Heimann, M.: A two-step scheme for high-resolution regional atmospheric trace gas inversions based on independent models, Atmos. Chem. Phys., 9, 5331–5342, doi{10.5194/acp-9-5331-2009}, 2009.

Roustan, Y. and Bocquet, M.: Inverse modelling for mercury over Europe, Atmos. Chem. Phys., 6, 3085–3098, doi{10.5194/acp-6-3085-2006}, 2006.

Rutter, A. P., Schauer, J. J., Lough, G. C., Snyder, D. C., Kolb, C. J., Von Klooster, S., Rudolf, T., Manolopoulos, H., and Olson, M. L.: A comparison of speciated atmospheric mercury at an urban center and an upwind rural location, J. Environ. Monitor., 10, 102–108, <a href="http://dx.doi.org/10.1039/b710247j">https://doi.org/10.1039/b710247j</a>, 2008.

Schroeder, W. and Munthe, J.: Atmospheric mercury – An overview, Atmos. Environ., 32, 809–822, <a href="http://dx.doi.org/10.1016/S1352-2310(97)00293-8">https://doi.org/10.1016/S1352-2310(97)00293-8</a>, 4th International Conference on Mercury as a Global Pollutant, Hamburg, Germany, AUG 04-08, 1996, 1998.

Seibert, P.: Inverse modelling of sulfur emissions in Europe based on trajectories, in: Inverse Methods in Global Biogeochemical Cycles, edited by: Kasibhatla, P., Heimann, M., Rayner, P., Mahowald, N., Prinn, R. G., and Hartley, D. E., 114, Geophys. Monogr., 147–154, Am. Geophys. Union, 2000.

Seibert, P., Kromp-Kolb, H., Baltensperger, U., Jost, D. T., and Schwikowski, M.: Trajectory analysis of high-alpine air pollution data, in: Air Pollution Modelling and its Application X, edited by: Gryning, S.-E. and Millan, M. M., pp. 595–596, Plenum Press, New York, USA, 1994.

Seigneur, C.: Estimating the Contribution of Coal-Fired Power Plants to the Atmospheric Deposition of Mercury in Wisconsin, Tech. Rep. CP263-1a, Atmospheric and Environmental Research, Inc., 2007.

Seigneur, C., Vijayaraghavan, K., Lohman, K., Karamchandani, P., and Scott, C.: Global source attribution for mercury deposition in the United States, Environ. Sci. Technol., 38, 555–569, <a href="http://dx.doi.org/10.1021/es034109t">https://doi.org/10.1021/es034109t</a>, 2004.

Selin, N. E.: Global Biogeochemical Cycling of Mercury: A Review, Ann. Rev. Environ. Resour., 34, 43–63, <a href="http://dx.doi.org/10.1146/annurev.environ.051308.084314">https://doi.org/10.1146/annurev.environ.051308.084314</a>, 2009.

Sherrod, D. R., Scott, W. E., and Stauffer, P. H.: A Volcano rekindled: The Renewed Eruption of Mount St. Helens, 2004–2006, Tech. rep., US Geological Survey, <a href="http://pubs.er.usgs.gov/publication/pp1750">http://pubs.er.usgs.gov/publication/pp1750</a>, 2008.

Sigler, J. M., Mao, H., and Talbot, R.: Gaseous elemental and reactive mercury in Southern New Hampshire, Atmos. Chem. Phys., 9, 1929–1942, doi{10.5194/acp-9-1929-2009}, 2009.

Skamarock, W. C., Klemp, J. B., Dudhia, J., Gill, D. O., Barker, D. M., Wang, W., and Powers, J. G.: A Description of the Advanced Research WRF Version 2, Tech. Rep. NCAR/TN-468+STR, NCAR, 2005.

Slemr, F., Brunke, E. G., Ebinghaus, R., and Kuss, J.: Worldwide trend of atmospheric mercury since 1995, Atmos. Chem. Phys., 11, 4779–4787, <a href="http://dx.doi.org/10.5194/acp-11-4779-2011">https://doi.org/10.5194/acp-11-4779-2011</a>, 2011.

Soerensen, A. L., Sunderland, E. M., Holmes, C. D., Jacob, D. J., Yantosca, R. M., Skov, H., Christensen, J. H., Strode, S. A., and Mason, R. P.: An Improved Global Model for Air-Sea Exchange of Mercury: High Concentrations over the North Atlantic, Environ. Sci. Technol., 44, 8574–8580, <a href="http://dx.doi.org/10.1021/es102032g">https://doi.org/10.1021/es102032g</a>, 2010.

Sprovieri, F., Pirrone, N., Ebinghaus, R., Kock, H., and Dommergue, A.: A review of worldwide atmospheric mercury measurements, Atmos. Chem. Phys., 10, 8245–8265, <a href="http://dx.doi.org/10.5194/acp-10-8245-2010">https://doi.org/10.5194/acp-10-8245-2010</a>, 2010.

Stohl, A., Forster, C., Frank, A., Seibert, P., and Wotawa, G.: Technical note: The Lagrangian} particle dispersion model FLEXPART version 6.2, Atmos. Chem. Phys., 5, 2461–2474, doi{10.5194/acp-5-2461-2005, 2005.

Stohl, A., Seibert, P., Arduini, J., Eckhardt, S., Fraser, P., Greally, B. R., Lunder, C., Maione, M., Muehle, J., O'Doherty, S., Prinn, R. G., Reimann, S., Saito, T., Schmidbauer, N., Simmonds, P. G., Vollmer, M. K., Weiss, R. F., and Yokouchi, Y.: An analytical inversion method for determining regional and global emissions of greenhouse gases: Sensitivity studies and application to halocarbons, Atmos. Chem. Phys., 9, 1597–1620, <a href="http://dx.doi.org/10.5194/acp-9-1597-2009">https://doi.org/10.5194/acp-9-1597-2009</a>, 2009.

Streets, D. G., Devane, M. K., Lu, Z., Bond, T. C., Sunderland, E. M., and Jacob, D. J.: All-Time Releases of Mercury to the Atmosphere from Human Activities, Environ. Sci. Technol., 45, 10485–10491, <a href="http://dx.doi.org/10.1021/es202765m">https://doi.org/10.1021/es202765m</a>, 2011.

Tarantola, A.: Inverse Problem Theory, Methods for Data Fitting and Model Parameter Estimation, Elsevier, Philadelphia, PA, USA, p. 64, 1987.

Thompson, R. L., Gerbig, C., and Roedenbeck, C.: A Bayesian inversion estimate of N2O emissions for western and central Europe and the assessment of aggregation errors, Atmos. Chem. Phys., 11, 3443–3458, <a href="http://dx.doi.org/10.5194/acp-11-3443-2011">https://doi.org/10.5194/acp-11-3443-2011</a>, 2011.

Thordarson, T. and Larsen, G.: Volcanism in Iceland in historical time: Volcano types, eruption styles and eruptive history, Journal of Geodynamics, 43, 118–152, <a href="http://dx.doi.org/10.1016/j.jog.2006.09.005">https://doi.org/10.1016/j.jog.2006.09.005</a>, 2007.

Vette, A., Landis, M., and Keeler, G.: Deposition and emission of gaseous mercury to and from Lake Michigan during the Lake Michigan Mass Balance Study (July, 1994 October, 1995), Environ. Sci. Technol., 36, 4525–4532, <a href="http://dx.doi.org/10.1021/es0112184">https://doi.org/10.1021/es0112184</a>, 2002.

Wanninkhof, R.: Relationship Between Wind Speed and Gas Exchange Over the Ocean, J. Geophys. Res.-Atmos., 97, 7373–7382, 1992.

Wen, D., Lin, J. C., Meng, F., Gbor, P. K., He, Z., and Sloan, J. J.: Quantitative assessment of upstream source influences on total gaseous mercury observations in Ontario, Canada, Atmos. Chem. Phys., 11, 1405–1415, <a href="http://dx.doi.org/10.5194/acp-11-1405-2011">https://doi.org/10.5194/acp-11-1405-2011</a>, 2011.

Wiedinmyer, C. and Friedli, H.: Mercury emission estimates from fires: An initial inventory for the United States, Environ. Sci. Technol., 41, 8092–8098, <a href="http://dx.doi.org/10.1021/es071289o">https://doi.org/10.1021/es071289o</a>, 2007.

Wiedinmyer, C., Quayle, B., Geron, C., Belote, A., McKenzie, D., Zhang, X., O'Neill, S., and Wynne, K. K.: Estimating emissions from fires in North America for air quality modeling, Atmos. Environ., 40, 3419–3432, <a href="http://dx.doi.org/10.1016/j.atmosenv.2006.02.010">https://doi.org/10.1016/j.atmosenv.2006.02.010</a>, 2006.

Wiedinmyer, C., Akagi, S. K., Yokelson, R. J., Emmons, L. K., Al-Saadi, J. A., Orlando, J. J., and Soja, A. J.: The Fire INventory from NCAR (FINN): a high resolution global model to estimate the emissions from open burning, Geosci. Model Dev., 4, 625–641, <a href="http://dx.doi.org/10.5194/gmd-4-625-2011">https://doi.org/10.5194/gmd-4-625-2011</a>, 2011.

Wunsch, C.: Discrete Inverse and State Estimation Problems: With Geophysical Fluid Applications, Cambridge University Press, 2006.

Yarwood, G., Lau, S., Jia, Y., Karamchandani, P., and Vijayaraghavan, K.: Modeling Atmospheric Mercury Chemistry and Deposition with CAMx for a 2002 Annual Simulations, Tech. rep., ENVIRON International Corporation, 2003.