ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-12-4181-2012 Speciated mercury at marine, coastal, and inland sites in New England – Part 2: Relationships with atmospheric physical parameters Mao H. 1 Talbot R. 2 Hegarty J. 3 Koermer J. 4 Department of Chemistry, State University of New York, College of Environmental Science and Technology, Syracuse, NY 13219, USA Department of Earth and Atmospheric Sciences, University of Houston, Houston, TX 77204, USA AER, Inc., 131 Hartwell Avenue, Lexington, MA, 02421, USA Department of Atmospheric Science & Chemistry, Plymouth State University, Plymouth, New Hampshire 03264, USA 11 05 2012 12 9 4181 4206 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/12/4181/2012/acp-12-4181-2012.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/12/4181/2012/acp-12-4181-2012.pdf

Long-term continuous measurements of gaseous elemental mercury (Hg<sup>0</sup>), reactive gaseous mercury (RGM), and particulate phase mercury (Hg<sup>P</sup>) were conducted at coastal (Thompson Farm, denoted as TF), marine (Appledore Island, denoted as AI), and elevated inland rural (Pac Monadnock, denoted as PM) monitoring sites of the AIRMAP Observing Network. Diurnal, seasonal, annual, and interannual variability in Hg<sup>0</sup>, RGM, and Hg<sup>P</sup> from the three distinctly different environments were characterized and compared in Part 1. Here in Part 2 relationships between speciated mercury (i.e., Hg<sup>0</sup>, RGM, and Hg<sup>P</sup>) and climate variables (e.g., temperature, wind speed, humidity, solar radiation, and precipitation) were examined. The best point-to-point correlations were found between Hg<sup>0</sup> and temperature in summer at TF and spring at PM, but there was no similar correlation at AI. Subsets of data demonstrated regional impacts of episodic dynamic processes such as strong cyclonic systems on ambient levels of Hg<sup>0</sup> at all three sites, possibly through enhanced oceanic evasion of Hg<sup>0</sup>. A tendency of higher levels of RGM and Hg<sup>P</sup> was identified in spring and summer under sunny conditions in all environments. Specifically, the 10th, 25th, median, 75th, and 90th percentile mixing ratios of RGM and Hg<sup>P</sup> increased with stronger solar radiation at both the coastal and marine sites. These metrics decreased with increasing wind speed at AI indicating enhanced loss of RGM and Hg<sup>P</sup> through deposition. RGM and Hg<sup>P</sup> levels correlated with temperature positively in spring, summer and fall at the coastal and marine locations. At the coastal site relationships between RGM and relative humidity suggested a clear decreasing tendency in all metrics from <40% to 100% relative humidity in all seasons especially in spring, compared to less variability in the marine environment. The effect of precipitation on RGM at coastal and marine locations was similar. At the coastal site, RGM levels were a factor of 3–4 to two orders of magnitude higher under dry conditions than rainy conditions in all seasons. In winter RGM mixing ratios appeared to be mostly above the limit of detection (LOD) during snowfalls suggesting less scavenging efficiency of snow. Mixing ratios of Hg<sup>P</sup> at the coastal and marine sites remained above the LOD under rainy conditions. Precipitation had negligible impact on the magnitude and pattern of diurnal variation of Hg<sup>P</sup> in all seasons in the marine environment.

 References Ames, M., Gullu, G., and Olmez, I.: Atmospheric mercury in the vapor phase, and in fine and coarse particulate matter at Perch River, New York, Atmos. Environ., 32, 865–872, 1998. Aucott, M. L., Caldarelli, A. D., Zsolway, R. R., Pietarinen, C. B., and England, R.: Ambient elemental, reactive gaseous, and particle-bound mercury concentrations in New Jersey, U.S.: measurements and association with wind direction, Environ. Monit. Assess., 158, 295–306, 2009. Baya, A. P. and Van Heyst, B.: Assessing the trends and effects of environmental parameters on the behaviour of mercury in the lower atmosphere over cropped land over four seasons, Atmos. Chem. Phys., 10, 8617–8628, http://dx.doi.org/10.5194/acp-10-8617-2010doi:10.5194/acp-10-8617-2010, 2010. Brooks, S., Luke, W., Cohen, M., Kelly, P., Lefer, B., and Rappenglück, B.: Mercury species measured atop the Moody Tower TRAMP site, Houston, Texas, Atmos. Envrion., 44, 4045–4055, 2010. Castillo, A., Valdes, J., Sibaja, J., Vega, I., Alfaro, R., Morales, J., Esquivel, G., Barrantes, E., Black, P., and Lean, D.: Seasonal and diel patterns of total gaseous mercury concentration in the atmosphere of the Central Valley of Costa Rica, Appl. Geochem., 26, 242–248, 2011. Cobbetta, F. D., Steffen, A., Lawson, G., and Van Heyst, B. J.: GEM fluxes and atmospheric mercury concentrations (GEM, RGM and Hg$^P)$ in the Canadian Arctic at Alert, Nunavut, Canada (February–June 2005), Atmos. Environ., 41, 6527–6543, 2007. Cole, A. S. and Steffen, A.: Trends in long-term gaseous mercury observations in the Arctic and effects of temperature and other atmospheric conditions, Atmos. Chem. Phys., 10, 4661–4672, http://dx.doi.org/10.5194/acp-10-4661-2010doi:10.5194/acp-10-4661-2010, 2010. Engle, M. A., Tate, M. T., Krabbenhoft, D. P., Kolker, A., Olson, M. L., Edgerton, E. S., DeWild, J. F., and McPherson, A. K.: Characterization and cycling of atmospheric mercury along the central U.S. Gulf Coast, Appl. Geochem., 23, 419–437, http://dx.doi.org/10.1016/j.apgeochem.2007.12.024doi:10.1016/j.apgeochem.2007.12.024, 2008. Faïn, X., Obrist, D., Hallar, A. G., Mccubbin, I., and Rahn, T.: High levels of reactive gaseous mercury observed at a high elevation research laboratory in the Rocky Mountains, Atmos. Chem. Phys., 9, 8049–8060, http://dx.doi.org/10.5194/acp-9-8049-2009doi:10.5194/acp-9-8049-2009, 2009. Feddersen, D., Talbot, R., Mao, H., and Sive, B.: Size distribution of Atmospheric particulate mercury in marine and coastal atmospheres, Atmos. Chem. Phys. Discuss., accepted, 2012. Gårdfeldt, K., Sommar, J., Ferrara, R., Ceccarini, C., Lanzilotta, E., Munthe, J., Wangberg, I., Lindqvist, O., Pirrone, N., Sprovieri, P., and Pesenti, E.: Evasion of mercury from Atlantic coastal water and the Mediterranean sea, coastal and open water, Atmos. Environ., 37, Suppl. 1, 73–84, 2003. Gabriel, M. C., Williamson, D. G., Brooks, S., and Lindberg, S.: Atmospheric speciation of mercury in two contrasting Southeastern US airsheds, Atmos. Environ., 39, 4947–4958, 2005. Han, Y.-J., Holsen, T. M., Lai, S.-O., Hopke, P. K., Yi, S.-M., Liu, W., Pagano, J., Falanga, L., Milligan, M., and Andolina, C.: Atmospheric gaseous mercury concentrations in New York State: relationships with meteorological data and other pollutants, Atmos. Environ., 38, 6431–6446, 2004. Holmes, C. D., Jacob, D. J., Mason, R. P., and Jaffe, D. A.: Sources and deposition of reactive gaseous mercury in the marine atmosphere, Atmos. Environ., 43, 2278–2285, 2009. Jacob, D. and Winner, D. A.: Effect of climate change on air quality, Atmos. Environ., 43, 51–63, 2009. Kock, H. H., Bieber, E., Ebinghaus, R., Spain, T. G., and Thees, B.: Comparison of long-term trends and seasonal variations of atmospheric mercury concentrations at the two European coastal monitoring stations Mace Head, Ireland, and Zingst, Germany, Atmos. Environ., 39, 7549–7556, 2005. Laurier, F. J. G., Mason, R. P., and Whalin, L.: Reactive gaseous mercury formation in the North Pacific Ocean's marine boundary layer: A potential role of halogen chemistry, J. Geophys. Res., 108, 4529, http://dx.doi.org/10.1029/2003JD003625doi:10.1029/2003JD003625, 2003. Laurier, F. and Mason, R.: Mercury concentration and speciation in the coastal and open ocean boundary layer, J. Geophys. Res., 112, D06302, http://dx.doi.org/10.1029/2006JD007320doi:10.1029/2006JD007320, 2007. Li, Z., Xia, C., Wang, X., Xiang, Y., and Xie, Z.: Total gaseous mercury in Pearl River Delta region, China during 2008 winter period, Atmos. Environ., 45, 834–838, 2011. Lin, C.-J. and Pehkonen, S. O.: The chemistry of atmospheric mercury : a review, Atmos. Environ., 33, 2067–2079, 1999. Liu, B., Keeler, G. J., Dvonch, J. T, Barres, J. A., Lynam, M. M., Marsik, F. J., and Morgan, J. T.: Temporal variability of mercury speciation in urban air, Atmos. Environ., 41, 1911–1923, 2007. Lombard, M. A. S., Bryce, J. G., Mao, H., and Talbot, R.: Mercury deposition in Southern New Hampshire, 2006–2009, Atmos. Chem. Phys., 11, 7657–7668, http://dx.doi.org/10.5194/acp-11-7657-2011doi:10.5194/acp-11-7657-2011, 2011. Mao, H. and Talbot, R.: O<sub>3</sub> and CO in New England: Temporal variations and relationships, J. Geophys. Res., 109, D21304, http://dx.doi.org/10.1029/2004JD004913doi:10.1029/2004JD004913, 2004a. Mao, H. and Talbot, R.: The role of meteorological processes in two New England ozone episodes during summer 2001, J. Geophys. Res., 109, D20305, http://dx.doi.org/10.1029/2004JD004850doi:10.1029/2004JD004850, 2004b. Mao, H., Talbot, R. W., Sigler, J. M., Sive, B. C., and Hegarty, J. D.: Seasonal and diurnal variations of Hg$^0$ over New England, Atmos. Chem. Phys., 8, 1403–1421, http://dx.doi.org/10.5194/acp-8-1403-2008doi:10.5194/acp-8-1403-2008, 2008. Mao, H. and Talbot, R.: Speciated mercury at marine, coastal, and inland sites in New England – Part 1: Temporal variability, Atmos. Chem. Phys. Discuss., 11, 32301–32336, http://dx.doi.org/10.5194/acpd-11-32301-2011doi:10.5194/acpd-11-32301-2011, 2011. Mao, H., and Talbot, R., et al.: Speciated Mercury at Marine, Coastal, and Inland Sites in New England: Part III. Relationships with Key Trace Gases, Atmos. Chem. Phys. Discuss., in preparation, 2012. Mason, R. P. and Sheu, G.-R.: Role of the ocean in the global mercury cycle, Global Biogeochem. Cy., 16, 1093, http://dx.doi.org/10.1029/2001GB001440doi:10.1029/2001GB001440, 2002. Pirrone, N., Hedgecock, I. M., and Forlano, L.: The role of the ambient aerosol in the atmospheric processingof semivolatile contaminants: A parameterised numerical model (gaspar), J. Geophys. Res., 105, 9773–9790, 2000. Poissant, L. and Casimir, A.: Water-air and soil-air exchange rate of total gaseous mercury at background sites, Atmos. Environ., 32, 883–893, 1998. Poissant, L., Pilote, M., Xu, X., Zhang, H., and Beauvais, C.: Atmospheric mercury speciation and deposition in the Bay St. François wetlands, J. Geophys. Res., 109, D11301, doi:1029/2003JD004364, 2004. Poissant, L., Pilote, M., Xu, X., Beauvais, C., Constant, P., and Zhang, H.: A year of continuous measurements of three atmospheric mercury species in southern Quebec, Canada, Atmos. Environ., 39, 1275–1287, 2005. Rothenberg, S. E., McKee, L., Gilbreath, A., Yee, D., Connor, M., and Fu, X.: Short-range transport of atmospheric mercury to a rural, inland site, Atmos. Environ., 44, 1263–1273, 2010. Sigler, J. M. and Lee, X.: Gaseous mercury in background forest soil in the northeastern United States, J. Geophys. Res., 111, G02007, http://dx.doi.org/10.1029/2005JG000106doi:10.1029/2005JG000106, 2006. Sigler, J. M., Mao, H., and Talbot, R.: Gaseous elemental and reactive mercury in Southern New Hampshire, Atmos. Chem. Phys., 9, 1929–1942, http://dx.doi.org/10.5194/acp-9-1929-2009doi:10.5194/acp-9-1929-2009, 2009a. Sigler, J. M., Mao, H., Sive, B. C., and Talbot, R.: Oceanic influence on atmospheric mercury at coastal and inland sites: a springtime noreaster in New England, Atmos. Chem. Phys., 9, 4023–4030, http://dx.doi.org/10.5194/acp-9-4023-2009doi:10.5194/acp-9-4023-2009, 2009b. Sprovieri, F., Pirrone, N., and Sommar, J.: Mercury speciation in the marine boundary layer along a 6000 km cruise path around the Mediterranean Sea, Atmos. Environ., 37, Suppl. 1, S63–S71, 2003. Stamenkovic, J., Lyman, S., and Gustin, M. S.: Seasonal and diel variation of atmospheric mercury concentrations in the Reno (Nevada, USA) airshed, Atmos. Environ., 41, 6662–6672, 2007. Talbot, R., Mao, H., Feddersen, D., Smith, M., Kim, S. Y., Sive, B., Haase, K., Ambrose, J., Zhou, and Russo R.: Comparison of particulate mercury measured with manual and Y. automated methods, Atmosphere, 2, 1–20, http://dx.doi.org/10.3390/atmos2010001doi:10.3390/atmos2010001, 2011. \hack Yatavelli, R. L. N., Fahrni, J. K., Kim, M., Crist, K. C., Vickers, C. D., Winter, S. E., and Connell, D. P.: Mercury, PM$_2.5$ and gaseous co-pollutants in the Ohio River Valley region: Preliminary results from the Athens supersite, Atmos. Environ., 40, 6650–6665, 2006. Zhou, Y., Mao, H., Russo, R. S., Blake, D. R., Wingenter, O. W., Haase, K. B., Varner, R. K., Talbot, R., and Sive, B. C.: Bromoform and dibromomethane measurements in the seacoast region of New Hampshire, 2002–2004, J. Geophys. Res., 113, D08305, http://dx.doi.org/10.1029/2007JD009103doi:10.1029/2007JD009103, 2008.