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Mapping Atmospheric Mercury in Lampung Province, Indonesia Using Bark of Multipurpose Tree Species. ATMOSPHERE 2021. [DOI: 10.3390/atmos13010002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The use of mercury in gold refining causes air pollution and results in the contamination of multipurpose tree species (MPTS). Tree bark has properties that cause it to store mercury for quite a long time. The purpose of this study was to determine mercury contamination of MPTS and map the mercury contamination distribution in the atmosphere using tree barks as bioindicators. Sampling was performed using purposive sampling. The mercury concentration was obtained by atomic absorption spectroscopy, and the highest THg contents were analyzed using a scanning electron microscope. The analysis was carried out by gauging total mercury (THg), distance, elevation to THg, and interpolation of THg at the research site. The results showed that there were 10 types of MPTS trees whose bark could accumulate mercury. The bark of the Tamarindus indica tree stored the greatest amount of THg (74.4 µg dry weight (DW)), followed by Persea americana (58.7 µg DW), and Annona muricata (44.2 µg DW), respectively. This result was influenced by the roughness of the bark and the location of the plants. No correlation was found between distance and elevation to THg on tree bark. The mercury interpolation in the atmosphere showed that mercury moves from the purification point to the southeast of the purification location.
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Weiss-Penzias P, Sorooshian A, Coale K, Heim W, Crosbie E, Dadashazar H, MacDonald AB, Wang Z, Jonsson H. Aircraft Measurements of Total Mercury and Monomethyl Mercury in Summertime Marine Stratus Cloudwater from Coastal California, USA. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:2527-2537. [PMID: 29401398 DOI: 10.1021/acs.est.7b05395] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Water samples from marine stratus clouds were collected during 16 aircraft flights above the Pacific Ocean near the Central California coast during the summer of 2016. These samples were analyzed for total mercury (THg), monomethyl mercury (MMHg), and 32 other chemical species in addition to aerosol physical parameters. The mean concentrations of THg and MMHg in the cloudwater samples were 9.2 ± 6.0 ng L-1 (2.3-33.8 ng L-1) ( N = 97) and 0.87 ± 0.66 ng L-1 (0.17-2.9 ng L-1) ( N = 22), respectively. This corresponds to 9.5% (3-21%) MMHg as a fraction of THg. Low and high nonsea salt calcium ion (nss-Ca2+) concentrations in cloudwater were used to classify flights as "marine" and "continental", respectively. Mean [MMHg]marine was significantly higher ( p < 0.05) than [MMHg]continental consistent with an ocean source of dimethyl Hg (DMHg) to the atmosphere. Mean THg in cloudwater was not significantly different between the two categories, indicating multiple emissions sources. Mean [THg]continental was correlated with pH, CO, NO3-, NH4+, and other trace metals, whereas [THg]marine was correlated with MMHg and Na+. THg concentrations were negatively correlated with altitude, consistent with ocean and land emissions, coupled with removal at the cloud-top due to drizzle formation.
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Affiliation(s)
- Peter Weiss-Penzias
- Department of Microbiology and Environmental Toxicology , University of California at Santa Cruz , Santa Cruz , California 95064 , United States
| | - Armin Sorooshian
- Department of Chemical and Environmental Engineering , University of Arizona , Tucson , Arizona 85721 , United States
- Department of Hydrology and Atmospheric Sciences , University of Arizona , Tucson , Arizona 85721 , United States
| | - Kenneth Coale
- Moss Landing Marine Laboratories , Moss Landing , California 95039 , United States
| | - Wesley Heim
- Moss Landing Marine Laboratories , Moss Landing , California 95039 , United States
| | - Ewan Crosbie
- NASA Langley Research Center , Hampton , Virginia 23666 , United States
| | - Hossein Dadashazar
- Department of Chemical and Environmental Engineering , University of Arizona , Tucson , Arizona 85721 , United States
| | - Alexander B MacDonald
- Department of Chemical and Environmental Engineering , University of Arizona , Tucson , Arizona 85721 , United States
| | - Zhen Wang
- Department of Chemical and Environmental Engineering , University of Arizona , Tucson , Arizona 85721 , United States
| | - Haflidi Jonsson
- Naval Postgraduate School , Monterey , California 93943 , United States
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Mondal P, de Alcântara Mendes R, Jonathan MP, Biswas JK, Murugan K, Sarkar SK. Seasonal assessment of trace element contamination in intertidal sediments of the meso-macrotidal Hooghly (Ganges) River Estuary with a note on mercury speciation. MARINE POLLUTION BULLETIN 2018; 127:117-130. [PMID: 29475643 DOI: 10.1016/j.marpolbul.2017.11.041] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Revised: 11/13/2017] [Accepted: 11/20/2017] [Indexed: 06/08/2023]
Abstract
The spatial and seasonal distribution of trace elements (TEs) (n=16) in surficial sediment were examined along the Hooghly River Estuary (~175km), India. A synchronous elevation of majority of TEs concentration (mgkg-1) was encountered during monsoon with the following descending order: Al (67070); Fe (31300); Cd (5.73); Cr (71.17); Cu (29.09); Mn (658.74); Ni (35.89). An overall low and homogeneous concentration of total Hg (THg=17.85±4.98ngg-1) was recorded in which methyl mercury (MeHg) shared minor fraction (8-31%) of the THg. Sediment pollution indices, viz. geo-accumulation index (Igeo) and enrichment factor (EF) for Cd (Igeo=1.92-3.67; EF=13.83-31.17) and Ba (Igeo=0.79-5.03; EF=5.79-108.94) suggested high contamination from anthropogenic sources. From factor analysis it was inferred that TEs primarily originated from lithogenic sources. This study would provide the latest benchmark of TE pollution along with the first record of MeHg in this fluvial system which recommends reliable monitoring to safeguard geochemical health of this stressed environment.
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Affiliation(s)
- Priyanka Mondal
- Department of Marine Science, University of Calcutta, 35 Ballygunge Circular Road, Calcutta 700019, India
| | | | - M P Jonathan
- Centro Interdisciplinario de Investigaciones y Estudios sobre Medio Ambiente y Desarrollo (CIIEMAD), Instituto Politécnico Nacional (IPN), Calle 30 de Junio de 1520, Barrio la Laguna Ticoman, Del. Gustavo A. Madero, C.P. 07340 Ciudad de México, Mexico
| | - Jayanta Kumar Biswas
- Department of Ecological Studies, International Centre for Ecological Engineering, University of Kalyani, Nadia 741235, India
| | | | - Santosh Kumar Sarkar
- Department of Marine Science, University of Calcutta, 35 Ballygunge Circular Road, Calcutta 700019, India.
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Ariya PA, Amyot M, Dastoor A, Deeds D, Feinberg A, Kos G, Poulain A, Ryjkov A, Semeniuk K, Subir M, Toyota K. Mercury Physicochemical and Biogeochemical Transformation in the Atmosphere and at Atmospheric Interfaces: A Review and Future Directions. Chem Rev 2015; 115:3760-802. [DOI: 10.1021/cr500667e] [Citation(s) in RCA: 228] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
| | - Marc Amyot
- Department
of Biological Sciences, Université de Montréal, 90
avenue Vincent-d’Indy, Montreal, Quebec, Canada, H3C 3J7
| | - Ashu Dastoor
- Air
Quality Research Division, Environment Canada, 2121 TransCanada Highway, Dorval, Quebec, Canada, H9P 1J3
| | | | | | | | - Alexandre Poulain
- Department
of Biology, University of Ottawa, 30 Marie Curie, Ottawa, Ontario, Canada, K1N 6N5
| | - Andrei Ryjkov
- Air
Quality Research Division, Environment Canada, 2121 TransCanada Highway, Dorval, Quebec, Canada, H9P 1J3
| | - Kirill Semeniuk
- Air
Quality Research Division, Environment Canada, 2121 TransCanada Highway, Dorval, Quebec, Canada, H9P 1J3
| | - M. Subir
- Department
of Chemistry, Ball State University, 2000 West University Avenue, Muncie, Indiana 47306, United States
| | - Kenjiro Toyota
- Air
Quality Research Division, Environment Canada, 4905 Dufferin Street, Toronto, Ontario, Canada, M3H 5T4
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Steffen A, Lehnherr I, Cole A, Ariya P, Dastoor A, Durnford D, Kirk J, Pilote M. Atmospheric mercury in the Canadian Arctic. Part I: a review of recent field measurements. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 509-510:3-15. [PMID: 25497576 DOI: 10.1016/j.scitotenv.2014.10.109] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 10/27/2014] [Accepted: 10/31/2014] [Indexed: 06/04/2023]
Abstract
Long-range atmospheric transport and deposition are important sources of mercury (Hg) to Arctic aquatic and terrestrial ecosystems. We review here recent progress made in the study of the transport, transformation, deposition and reemission of atmospheric Hg in the Canadian Arctic, focusing on field measurements (see Dastoor et al., this issue for a review of modeling studies on the same topics). Redox processes control the speciation of atmospheric Hg, and thus impart an important influence on Hg deposition, particularly during atmospheric mercury depletion events (AMDEs). Bromine radicals were identified as the primary oxidant of atmospheric Hg during AMDEs. Since the start of monitoring at Alert (NU) in 1995, the timing of peak AMDE occurrence has shifted to earlier times in the spring (from May to April) in recent years, and while AMDE frequency and GEM concentrations are correlated with local meteorological conditions, the reasons for this timing-shift are not understood. Mercury is subject to various post-depositional processes in snowpacks and a large portion of deposited oxidized Hg can be reemitted following photoreduction; how much Hg is deposited and reemitted depends on geographical location, meteorological, vegetative and sea-ice conditions, as well as snow chemistry. Halide anions in the snow can stabilize Hg, therefore it is expected that a smaller fraction of deposited Hg will be reemitted from coastal snowpacks. Atmospheric gaseous Hg concentrations have decreased in some parts of the Arctic (e.g., Alert) from 2000 to 2009 but at a rate that was less than that at lower latitudes. Despite numerous recent advances, a number of knowledge gaps remain, including uncertainties in the identification of oxidized Hg species in the air (and how this relates to dry vs. wet deposition), physical-chemical processes in air, snow and water-especially over sea ice-and the relationship between these processes and climate change.
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Affiliation(s)
- Alexandra Steffen
- Environment Canada, Air Quality Processes Research, Toronto M3H 5T4, Ontario, Canada.
| | - Igor Lehnherr
- University of Waterloo, Department of Earth and Environmental Sciences, Waterloo N2L 3G1, Ontario, Canada
| | - Amanda Cole
- Environment Canada, Air Quality Processes Research, Toronto M3H 5T4, Ontario, Canada
| | - Parisa Ariya
- McGill University, Department of Chemistry, 801 Sherbrooke St. W., Montreal H3A 2K6, Quebec, Canada; McGill University, Department of Atmospheric and Oceanic Sciences, 801 Sherbrooke St. W., Montreal H3A 2K6, Quebec, Canada
| | - Ashu Dastoor
- Environment Canada, National Prediction Development Division, Dorval H9P 1J3, Quebec, Canada
| | - Dorothy Durnford
- Environment Canada, National Prediction Development Division, Dorval H9P 1J3, Quebec, Canada
| | - Jane Kirk
- Environment Canada, Aquatic Contaminants Research Division, Burlington L7R 4A6, Ontario, Canada
| | - Martin Pilote
- Environment Canada, Aquatic Contaminants Research Division, Montreal H2Y 2E7, Quebec, Canada
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Moore CW, Obrist D, Steffen A, Staebler RM, Douglas TA, Richter A, Nghiem SV. Convective forcing of mercury and ozone in the Arctic boundary layer induced by leads in sea ice. Nature 2014; 506:81-4. [DOI: 10.1038/nature12924] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 11/29/2013] [Indexed: 11/09/2022]
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Durnford D, Dastoor A. The behavior of mercury in the cryosphere: A review of what we know from observations. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010jd014809] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Engle MA, Tate MT, Krabbenhoft DP, Schauer JJ, Kolker A, Shanley JB, Bothner MH. Comparison of atmospheric mercury speciation and deposition at nine sites across central and eastern North America. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2010jd014064] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Wan Q, Feng X, Lu J, Zheng W, Song X, Han S, Xu H. Atmospheric mercury in Changbai Mountain area, northeastern China I. The seasonal distribution pattern of total gaseous mercury and its potential sources. ENVIRONMENTAL RESEARCH 2009; 109:201-206. [PMID: 19185296 DOI: 10.1016/j.envres.2008.12.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2008] [Revised: 10/29/2008] [Accepted: 12/10/2008] [Indexed: 05/27/2023]
Abstract
An intensive field campaign for the measurement of total gaseous mercury (TGM) concentrations in ambient air was conducted in Changbai Mountain area from 5 August 2005 to 5 July 2006 using an automatic atmospheric mercury analyzer (Tekran 2537A), which was the first time TGM was monitored at a remote area in northeastern China. 99% of the hourly TGM concentrations fell between 1.28 and 9.49ngm(-3) with an annual arithmetic mean of 3.58+/-1.78ngm(-3), which was significantly elevated compared to values obtained in remote areas of Europe and North America. Seasonal mean TGM concentrations displayed a descending trend as follows: winter, spring, fall, and summer. Compared to spring/winter, TGM concentrations were lower in the summer/fall but the standard deviation (SD) of TGM levels was higher and indicated a correlation with anthropogenic emissions. TGM concentrations showed seasonal differences with respect to meteorological parameters: TGM levels in spring/winter were most correlated with wind speed, and correlated with solar radiation only in the winter, while TGM levels in summer/fall periods were most correlated with air temperature. There was a strong diurnal variation of seasonal TGM with significantly higher concentrations in daytime/nighttime compared to the early morning. The seasonal diel TGM pattern indicated regional biofuel and coal combustion were the primary mercury sources.
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Affiliation(s)
- Qi Wan
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, PR China
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Swartzendruber PC, Chand D, Jaffe DA, Smith J, Reidmiller D, Gratz L, Keeler J, Strode S, Jaeglé L, Talbot R. Vertical distribution of mercury, CO, ozone, and aerosol scattering coefficient in the Pacific Northwest during the spring 2006 INTEX-B campaign. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jd009579] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Radke LF, Friedli HR, Heikes BG. Atmospheric mercury over the NE Pacific during spring 2002: Gradients, residence time, upper troposphere lower stratosphere loss, and long-range transport. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2005jd005828] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Tackett PJ, Cavender AE, Keil AD, Shepson PB, Bottenheim JW, Morin S, Deary J, Steffen A, Doerge C. A study of the vertical scale of halogen chemistry in the Arctic troposphere during Polar Sunrise at Barrow, Alaska. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006jd007785] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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13
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Selin NE, Jacob DJ, Park RJ, Yantosca RM, Strode S, Jaeglé L, Jaffe D. Chemical cycling and deposition of atmospheric mercury: Global constraints from observations. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006jd007450] [Citation(s) in RCA: 290] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Swartzendruber PC, Jaffe DA, Prestbo EM, Weiss-Penzias P, Selin NE, Park R, Jacob DJ, Strode S, Jaeglé L. Observations of reactive gaseous mercury in the free troposphere at the Mount Bachelor Observatory. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2006jd007415] [Citation(s) in RCA: 132] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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15
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Wu Y, Wang S, Streets DG, Hao J, Chan M, Jiang J. Trends in anthropogenic mercury emissions in China from 1995 to 2003. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2006; 40:5312-8. [PMID: 16999104 DOI: 10.1021/es060406x] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
We have developed multiple-year inventories of anthropogenic mercury emissions in China for 1995 through 2003. We estimate that total Hg emissions from all anthropogenic sources increased at an average annual rate of 2.9% during the period 1995-2003, reaching 696 (+/- 307) t in 2003, with a speciation split of 395 t of Hg0, 230 t of Hg2+, and 70 t of Hg(p). Nonferrous metals smelting and coal combustion continue to be the two leading mercury sources in China, as nonferrous metals production and coal consumption keep increasing. Nonferrous metals smelting and coal combustion together contributed approximately 80% of total Hg emissions during the past decade. Hg emissions from coal combustion increased from 202 t in 1995 to 257 t in 2003 at an average annual rate of 3.0%. Among all of the coal consumption sectors, the power sector is the leading one in Hg emissions growth, up by 5.9% annually. Hg emissions from nonferrous metals smelting increased from 230 t in 1995 to 321 t in 2003 at an average annual rate of 4.2%. Although Hg emissions related to gold smelting decreased since 1996, other nonferrous metals such as zinc, lead, and copper contributed significant Hg growth at annual rates of 8.5%, 13.0%, and 6.9%, respectively. At provincial level, the trends of Hg emissions show significant variation. The uncertainty level decreased from +/- 78% (95% confidence interval) in the estimate of total emissions in 1995, to +/- 44% in 2003. This is primarily attributed to the decreased emissions from those Hg sources with the largest uncertainty in both activity levels and emission factors, such as artisanal gold smelting, mercury mining, and battery/fluorescent lamp production.
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Affiliation(s)
- Ye Wu
- Argonne National Laboratory, Argonne, Illinois 60439, USA.
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Steffen A, Schroeder W, Macdonald R, Poissant L, Konoplev A. Mercury in the Arctic atmosphere: an analysis of eight years of measurements of GEM at Alert (Canada) and a comparison with observations at Amderma (Russia) and Kuujjuarapik (Canada). THE SCIENCE OF THE TOTAL ENVIRONMENT 2005; 342:185-98. [PMID: 15866275 DOI: 10.1016/j.scitotenv.2004.12.048] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Eight years of gaseous elemental mercury (GEM) concentration measurements from Alert, Nunavut, Canada (between 1995 and 2002) is presented. The annual time series shows a distinct repeating seasonal pattern with an overall annual median concentration for this time period of 1.58 (S.D.=0.04 ng m(-3)). Strong seasonal variation was observed throughout the years with springtime displaying strong variability in the GEM and overall lower median concentrations due to the so-called mercury depletion events (MDEs). Summer concentrations are higher than the annual average and show a decrease in variability. Fall and winter concentrations are distributed around the annual median concentrations and show little variability. The relationship between the springtime depression and the summer increase shows a change in the behaviour of mercury between 1995 and 2002. Preliminary results suggest that during this period an increasing amount of the mercury lost from the atmosphere in the spring is not returned to atmosphere in summer. A comparison of GEM concentration data from three sites--Alert (Canada), Amderma (Russia) and Kuujjuarapik (Canada)--demonstrated similar monthly distribution of GEM between Alert and Amderma, with the latter not showing as high summer concentrations. Monthly distribution of GEM at Kuujjuarapik varied considerably from the other two sites. MDEs were found to occur at each site in the spring yet displayed different characteristics. MDEs appear to start at Alert shortly after polar sunrise but in Amderma their initiation is delayed approximately 2 months following polar sunrise. MDEs occur in Kuujjuarapik in the springtime despite an incomplete development of the polar day-night cycle. In spring, as soon as air temperature attained temperatures consistently above 0 degrees C, MDEs ended immediately at all three sites. Continued studies into MDEs are warranted, but clearly an important component of future studies must focus on the origins of the variation of GEM behaviour at different sites.
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Affiliation(s)
- Alexandra Steffen
- Meteorological Service of Canada, 4905 Dufferin Street, Toronto, Ontario, Canada M3H 5T4.
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Hedgecock IM, Pirrone N. Chasing quicksilver: modeling the atmospheric lifetime of Hg(0)(g) in the marine boundary layer at various latitudes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2004; 38:69-76. [PMID: 14740719 DOI: 10.1021/es034623z] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The lifetime of elemental mercury in the marine boundary layer(MBL) has been studied using AMCOTS (Atmospheric Mercury Chemistry Over The Sea), a box model of MBL photochemistry including aerosols and detailed mercury chemistry. Recently measured Hg(0)(g) oxidation reactions have been included, and the studies were performed as a function of latitude, time of year, boundary layer liquid water content (LWC) and cloud optical depth. The results show that Hg has the shortest lifetime when air temperatures are low and sunlight and deliquescent aerosol particles are plentiful. Thus the modeled lifetime for clear-sky conditions is actually shorter at mid-latitudes and high latitudes than near the equator, and for a given latitude and time of year, cooler temperatures enhance the rate of Hg oxidation. Under typical summer conditions (for a given latitude) of temperature and cloudiness, the lifetime (tau) of Hg(0)(g) in the MBL is calculated to be around 10 days at all latitudes between the equator and 60 degrees N. This is much shorter than the generally accepted atmospheric residence time for Hg(0)(g) of a year or more. Given the relatively stable background concentrations of Hg(0)(g) which have been measured, continual replenishment of Hg(0)(g) must take place, suggesting a "multihop" mechanism for the distribution of Hg, rather than solely aeolian transport with little or no chemical transformation between source and receptor. Inclusion of an empirical Hg(0)(g) emission factor related to insolation was used to stabilize the Hg(0)(g) concentration in the model, and the emission rates necessarily agree well with estimated emission fluxes for the open ocean.
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Affiliation(s)
- Ian M Hedgecock
- CNR- Institute for Atmospheric Pollution, c/o UNICAL (Polifunzionale), Rende 87036, Italy.
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Friedli HR. Mercury in the atmosphere around Japan, Korea, and China as observed during the 2001 ACE-Asia field campaign: Measurements, distributions, sources, and implications. ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2003jd004244] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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