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Masahiro Sakata - One of the best experts on this subject based on the ideXlab platform.
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Atmospheric Dry Deposition of trace elements at a site on Asian-continent side of Japan
Atmospheric Environment, 2011Co-Authors: Masahiro Sakata, Kazuo AsakuraAbstract:The sources of Dry-deposited trace elements (As, Cd, Cr, Cu, Mn, Ni, Pb, Sb and V) and the factors controlling their Dry Deposition fluxes were investigated on the basis of two-year observations (April 2004–March 2006) at a site on the Asian-continent side of Japan, which has been strongly affected by air pollutants from the Asian continent. Dry Deposition sampling was conducted using a water surface sampler connected to a wet-only precipitation sampler. The Dry Deposition of As, Cd, Pb and Sb showed a small contribution to atmospheric Deposition (0.25–0.44 as ratios of annual Dry/wet Deposition fluxes). Moreover, the Dry Deposition fluxes of those elements increased negligibly during the period when their atmospheric particulate matter (PM) concentrations increased owing to transport from the Asian continent. Thus, the Dry Deposition of As, Cd, Pb and Sb from the Asian continent was not significant, because their overall Dry Deposition velocities are relatively low (mostly
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wet and Dry Deposition fluxes of trace elements in tokyo bay
Atmospheric Environment, 2008Co-Authors: Masahiro Sakata, Yukinori Tani, Tomoharu TakagiAbstract:Abstract The annual wet and Dry Deposition fluxes of As, Cd, Cr, Cu, Hg, Mn, Ni, Pb and V were measured on the basis of data obtained from 2 years of observation (December 2003–November 2005) at three sites in the Tokyo Bay area, which is highly affected by anthropogenic sources. Moreover, the concentrations of these trace elements in the air and bay sediments were determined concurrently. Using these data, we evaluated the factors affecting wet and Dry Deposition fluxes and the contribution of the atmospheric input of each element to the supply of trace elements to the bay. The order of the average ratios of Dry/wet Deposition fluxes at three sites was Cr, 6.9>As, 5.9>Mn, 4.7>V, 4.5>Cu, 4.4>Ni, 3.7>Cd, 2.9>Pb, 2.0>Hg, 1.0. Thus, the atmospheric Deposition of the trace elements except Hg in Tokyo Bay is predominantly Dry Deposition. For such trace elements, the wet and Dry Deposition fluxes within the bay were higher than those inland. Except in the case of some elements, the differences in wet and Dry Deposition fluxes between these sites were primarily due to the differences in scavenging ratio (=concentration in precipitation/concentration in air) and Dry Deposition velocity (=Deposition flux/concentration in air), respectively, rather than in atmospheric concentration. Also, a significant correlation (r2=0.76, P
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regional variations in wet and Dry Deposition fluxes of trace elements in japan
Atmospheric Environment, 2006Co-Authors: Masahiro Sakata, Kohji Marumoto, Masahiro Narukawa, Kazuo AsakuraAbstract:Abstract The annual wet and Dry Deposition fluxes of 12 trace elements (i.e., As, Cd, Cr, Cu, Hg, Mn, Mo, Ni, Pb, Sb, Se and V) were measured on the basis of 1 year of observations (December 2003–November 2004) at 10 sites in Japan. Precipitation and Dry Deposition (gases and particles) samples were collected every half month using an automatic sampler, which is composed of a precipitation sampler and a water surface sampler for Dry Deposition. The wet Deposition fluxes of Hg, Pb and Se exceeded their Dry Deposition fluxes at most sites. In contrast, the Dry Deposition fluxes of Cr, Cu, Mn, Mo, Ni and V were significantly higher than their wet Deposition fluxes. The annual wet Deposition fluxes of trace elements except for Cu, Mo and Ni were correlated with the annual precipitation amount ( P 0.05 ). In particular, about 70–80% of the variance of the wet Deposition fluxes for Hg ( r 2 = 0.80 ), Sb ( r 2 = 0.68 ) and V ( r 2 = 0.80 ) was explained using the precipitation amount. The wet Deposition fluxes of As, Cd, Pb and Se at sites on the Japan Sea coast tended to be higher than those expected from the precipitation amount. This suggests a large contribution of their long-range transport from the Asian continent. On the other hand, the regional variations in the Dry Deposition fluxes of the trace elements were different from those in the wet Deposition fluxes. A markedly higher Dry Deposition fluxes were observed at sites in industrial and urban areas. The relatively high Dry Deposition fluxes of Cr, Cu, Mn, Ni and Pb suggest that these elements are mainly from electric steel furnaces near the sites, because they are abundant in furnace emission particles. The results of lead isotope analyses indicate that the lead isotope ratios in the Dry Deposition samples at industrial and urban sites are different from those at other sites. This implies that lead Dry Deposition at such sites is dominated by emissions from peculiar sources, although whether those sources are the electric steel furnaces is unknown.
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wet and Dry Deposition fluxes of mercury in japan
Atmospheric Environment, 2005Co-Authors: Masahiro Sakata, Kohji MarumotoAbstract:Abstract Wet and Dry Deposition fluxes of mercury were measured concurrently from December 2002 to November 2003 at 10 sites in Japan (nine sites for Dry Deposition measurements). Precipitation and Dry Deposition (gases and particles) were collected every half-month using an automatic wet and Dry Deposition sampler. This sampler is composed of a precipitation sampler and a water surface sampler for Dry Deposition. The results showed that wet Deposition fluxes of mercury increase generally during summer when the precipitation amount increases. In contrast, the seasonal variations of the Dry Deposition fluxes were very small compared to those of the wet Deposition fluxes. It was found that wet Deposition plays a dominant role in mercury Deposition in Japan, contributing fluxes ranging from 0.99 to 2.2 times (1.6 times on average at nine sites) those of the Dry Deposition fluxes. There was a high correlation between the annual wet Deposition flux of mercury and annual precipitation amount ( r 2 = 0.73 , P 0.01 ). Thus, about 70% of the variance of mercury wet Deposition in Japan is explained by precipitation amount. This is probably because mercury wet Deposition is dominated by the scavenging of reactive gaseous mercury (RGM) by precipitation via oxidation of gaseous elemental mercury (Hg0) in the gas and aqueous phases. In addition, a similar relationship between the annual wet Deposition flux and precipitation amount ( r 2 = 0.55 , P 0.001 ) was observed at the Mercury Deposition Network (MDN) sites in North America, suggesting that about 55% of the variance of mercury wet Deposition is due to precipitation amount.
Mustafa Odabasi - One of the best experts on this subject based on the ideXlab platform.
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Wet and Dry Deposition of formaldehyde in Izmir, Turkey.
The Science of the total environment, 2005Co-Authors: Remzi Seyfioglu, Mustafa Odabasi, Eylem CetinAbstract:Samples were collected between May 2003 and May 2004 in Izmir, Turkey to measure Dry and wet Deposition of formaldehyde (HCHO). Particle-phase HCHO fluxes measured with Dry Deposition plates ranged between 2 and 56 microg m(-2) day(-1) (average+/-SD, 17+/-12 microg m(-2) day(-1)). Particulate phase Dry Deposition velocities calculated using the particulate fluxes measured and ambient particulate concentrations ranged from 0.1 to 9.6 cm s(-1) (1.4+/-1.4 cm s(-1)). The particulate overall Dry Deposition velocity agreed well with those measured previously for other pollutants using the same method. Formaldehyde concentration measured in 27 rain samples collected at the sampling site ranged between 10 and 304 microg l(-1). The annual formaldehyde wet Deposition was calculated as 31.4 mg m(-2) year(-1). The annual HCHO total Deposition (wet+Dry) was dominated by wet Deposition (83.7%).
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Dry Deposition fluxes and velocities of polychlorinated biphenyls (PCBs) associated with particles
Atmospheric Environment, 2004Co-Authors: Yücel Tasdemir, Mustafa Odabasi, Aysu Sofuoglu, Nedim Vardar, Thomas J. Murphy, Thomas M. HolsenAbstract:Abstract The interest in atmospheric Deposition by the scientific community has increased a great deal over the past several years because of its significant contribution to the pollution budget of many natural waters. Dry Deposition is an effective removal mechanism for polychlorinated biphenyls (PCBs) from the atmosphere. This study focuses on the understanding of the particulate Dry Deposition of PCBs in urban areas. In this paper, 43 chromatographic PCB congener peaks which represent 50 individual or coeluting congeners were evaluated. The PCB Dry Deposition fluxes were measured using a smooth, greased, knife-edge surrogate surface holding greased Mylar strips in Chicago, IL. The average PCB Dry Deposition flux measured (190±80 ng m−2 day−1) was similar to those measured in other urban areas. Ambient air samples were also collected simultaneously with flux samples. The average apparent Dry Deposition velocity, calculated by dividing the fluxes to the particle phase concentrations was 5.2±2.9 cm s−1. This value is in good agreement with the values calculated using similar techniques.
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Sulfate Dry Deposition fluxes and overall Deposition velocities measured with a surrogate surface.
The Science of the total environment, 2002Co-Authors: Mustafa Odabasi, H Ozgur BagirozAbstract:Previous studies have shown that the Dry Deposition of particulate sulfate can account for a significant fraction of its total (wet + Dry) Deposition. However, there is no generally accepted method to directly measure Dry Deposition. In this study, the particulate sulfate Dry Deposition was measured using a smooth surrogate surface between September 2000 and June 2001 in Izmir, Turkey. Concurrently, ambient air samples were collected. Average particulate sulfate fluxes and ambient concentrations were 49.3 +/- 24.3 mg m(-2) d(-1) and 11.2 +/- 6.6 microg m(-3), respectively. The measured particulate Dry Deposition fluxes were higher than those measured in other urban and rural areas. The contribution of marine and terrestrial sources was also estimated and found to be insignificant. The particulate phase overall Dry Deposition velocities calculated using the Dry Deposition fluxes and corresponding ambient concentrations averaged 6.3 +/- 3.9 cm s(-1). This value is higher than values typically used to estimate particulate sulfate Deposition; however, it is in good agreement with values determined using similar surrogate surface techniques.
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Particulate Dry Deposition and Overall Deposition Velocities of Polycyclic Aromatic Hydrocarbons
Journal of Environmental Engineering, 2002Co-Authors: Nedim Vardar, Mustafa Odabasi, Thomas M. HolsenAbstract:Previous studies have shown that the Dry Deposition of semivolatile organic compounds to the Great Lakes can account for a significant fraction of their total inputs. However, there is no generally accepted method to directly measure Dry Deposition. In this study the particulate Dry Deposition of polycyclic aromatic hydrocarbons (PAHs) was measured using smooth surrogate surfaces during the winter of 1996-1997 in Chicago. Concurrently, ambient air samples were collected. Average particulate Σ\D13\N-PAH fluxes and ambient concentrations were 120±28μg/m² d and 30±16ng/m³, respectively. The measured particulate Dry Deposition fluxes were similar to those measured in other urban areas. Overall Dry Deposition velocities of PAHs calculated using the Dry Deposition fluxes and ambient concentrations averaged 4.5±3.1 cm/s. This value is higher than values typically used to estimate PAH particulate Deposition, however, it agrees well with values determined using similar techniques. The overall Dry Deposition velocity for individual PAHs generally decreased with increasing molecular weight. This finding is consistent with the previous experimental studies that have shown that a greater fraction of the higher molecular weight PAHs are associated with fine particles relative to the lower molecular weight compounds.
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measurement of Dry Deposition and air water exchange of polycyclic aromatic hydrocarbons with the water surface sampler
Environmental Science & Technology, 1999Co-Authors: Mustafa Odabasi, Aysu Sofuoglu, Nedim Varda, Yucel Tasdemi, Thomas M HolseAbstract:Recent work has shown that Dry Deposition and gas exchange of semivolatile organic compounds in the Great Lakes is important. However, there is no generally accepted method for collecting particulate Dry Deposition or gas exchange. In this work the Water Surface Sampler (WSS) was modified and used in combination with Dry Deposition plates to measure the particulate Dry Deposition and gas exchange of PAHs. Simultaneous Dry Deposition and ambient air samples were collected between June and October 1995 in Chicago, IL. Total (particulate + gas) fluxes were measured with the WSS, while particulate fluxes were measured with Dry Deposition plates. Average Σ14-PAH and particulate Σ14-PAH fluxes were 360 ± 146 μg/m2 d and 144 ± 60 μg/m2 d, respectively. Gas-phase fluxes, determined by subtracting the Dry Deposition plate fluxes (particulate) from WSS fluxes (particulate + gas), averaged 170 ± 72 μg/m2 d. The measured particulate Dry Deposition and gas exchange fluxes were substantially higher than those previousl...
Guorcheng Fang - One of the best experts on this subject based on the ideXlab platform.
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measuring metallic elements of total suspended particulates tsps Dry Deposition flux and Dry Deposition velocity for seasonal variation in central taiwan
Atmospheric Research, 2014Co-Authors: Guorcheng Fang, Shyhchyi Chang, Yucheng Chen, Yuanjie ZhuangAbstract:Abstract The purposes of this study were to investigate and characterize ambient air particulate concentrations and Dry Deposition fluxes and those metallic elements associated with them in central Taiwan during 2009–2010. At the Bei-Shi (suburban/coastal) sampling site, the average TSP concentrations, flux, and Deposition velocity were 92.3 (μg m− 3), 165.92 (μg m− 2 min− 1), and 3 (cm s− 1), respectively. In addition, at the Quan-Xin (industrial) sampling site, the highest average TSP concentrations of As, ambient air particulate bound mercury (Hg(p)), Mn, Fe, Zn, Cr, Cu and Pb were 3.56, 0.07, 82.21, 2769.82, 109.33, 31.93, 109.76 and 39.15 ng m− 3, respectively. The highest average Dry Deposition flux of elements As, Hg(p), Mn, Fe, Zn, Cr, Cu and Pb were 2.36, 0.15, 18.11, 303.8, 35.59, 18.66, 45.47 and 42.6 (ng m− 2 min− 1), respectively in Quan-Xin (industrial). The median Deposition velocity (Vd) of metallic elements was present at the five characteristic sampling sites, respectively. However, the median Dry Deposition velocity (Vd) of Hg(p) was 2.73–4.78 cm s− 1, higher than all other elements in the five characteristic sampling sites during 2009–2010. The median Dry Deposition velocity (Vd) of Fe was 0.17–0.27 cm s− 1, lower than all other elements in the five characteristic sampling sites during 2009–2010.
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Use of Mercury Dry Deposition Samplers to Quantify Dry Deposition of Particulate-Bound Mercury and Reactive Gaseous Mercury at a Traffic Sampling Site
Environmental Forensics, 2013Co-Authors: Guorcheng Fang, Yen-heng Lin, Chia-ying ChangAbstract:A Dry Deposition plate (DDP), which collects particulate-bound mercury Hg(p) was used in this study (Fang et al., 2011a; 2011b). In addition, knife-edge surrogate surface (KSS) was used to collect ambient air particulate-bound mercury Hg(p) and reactive gaseous mercury (RGM) (Huang et al., 2011). The above two samplers were used to collect ambient air particulate-bound mercury Hg(p) and RGM at Huang-Kuang (traffic) sampling site during the daytime and nighttime sampling periods for this study. The results indicate that the mean rate of Dry Deposition of particle-bound mercury Hg(p) from ambient air, determined using the Dry Deposition plate, was 0.025 ng/m2*min and 0.018 ng/m2*min in the daytime and the nighttime sampling periods, respectively. The mean rate of Dry Deposition of particle-bound mercury Hg(p), collected using a KSS of quartz was 0.026 ng/m2*min and 0.018 ng/m2*min in the daytime and nighttime sampling periods, respectively. The mean rate of Dry Deposition of RGM collected from a KSS of an i...
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Dry Deposition of Atmospheric Particle-Bound Mercury in the Middle Taiwan
Aerosol and Air Quality Research, 2012Co-Authors: Guorcheng Fang, Jen-hsiung Tsai, Yan-heng Lin, Chia-ying ChangAbstract:Atmospheric particle-bound mercury Hg(p) concentrations and Dry Deposition were investigated at Westing Park and Taichung airport sampling sites in the middle of Taiwan during the years 2011 and 2012.The calculated/measured Dry Deposition flux ratios of ambient air particles and Hg(p) with Petroff and Zhang’s model were also studied. At the Westing Park sampling site, the particle-bound Hg(p) concentration and Hg (p) Dry Deposition velocity were 0.022 ng/m 3 and 1.74 cm/sec, respectively, while at the Taichung airport sampling site these were 0.027 ng/m 3 and 1.03 cm/sec, respectively. The average calculated/measured Dry Deposition flux ratios for ambient air particles and Hg(p) at average particle sizes of 10, 20 and 23 μm in were 0.79, 1.22, and 1.43, and 0.93, 1.43 and 1.69 at the Westing Park sampling site, respectively. The average calculated/measured Dry Deposition flux ratios for ambient air particles and Hg(p) at average particle sizes of 10, 20 and 23 μm were 0.92, 1.42, and 1.67, and 1.05, 1.61 and 1.90 at the Taichung airport sampling site, respectively. This study also found that Petroff and Zhang’s model produced the best for the prediction of ambient air particulates and Hg(p) Dry Deposition for a particle size of 10 μm at both the Westing Park and Taichung airport sampling sites, and that the results became worse as the particle size increased.
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Atmospheric Dry Deposition Fluxes of Metallic Pollutants in Asia During 1997–2006
Environmental Forensics, 2008Co-Authors: Guorcheng Fang, Tai-hua ChangAbstract:Numerous studies have monitored Deposition velocity and Dry Deposition fluxes in Asia throughout the recent decade. This study compares different sample collections, pretreatments, and analytical methods utilized throughout the past decade in Asia. Analytical results suggest that the primary Dry Deposition sources are traffic and soil exhaust. This study also elucidates the sources, analytical tools, and the average concentrations in the Asian region for Dry Deposition and related metallic elements during 1997–2006. The order of metallic elements in average Dry Deposition fluxes in Asia was established as: Na > K > Mg > Fe > Ca > Zn > Pb > Mn > Cl > Cu > Cd > Cr, and in average atmospheric concentrations the order was observed as: Ca > Cl > Na > Fe > Mg > K > Zn > Cu > Pb > Mn > Cr > Cd. The order of metallic elements in average Deposition velocity in Asia was Fe > Zn > Cd > Ca > Mn > Pb > Cr > Cu > Mg > Na > Cl > K.
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Dry Deposition study by using Dry Deposition plate and water surface sampler in Shalu, central Taiwan
Environmental Monitoring and Assessment, 2008Co-Authors: Chia-chun Chu, Guorcheng Fang, Jhy-cherng Chen, I-lin YangAbstract:This study presents the chemical composi- tion of Dry Deposition by using Dry Deposition plate and water surfaces sampler during daytime and nighttime sampling periods at a near highway traffic sampling site. In addition, the characterization for mass and water soluble species of total suspended particulate (TSP), PM2.5 and PM10 were also studied at this sampling site during August 22 to October 31 of 2006 around central Taiwan. The samples collected were analyzed by using Ion Chromatography (DIO NEX 100) for the ionic species analysis. Results of the particulate Dry Deposition fluxes are higher in the water surfaces sampler than that of the Dry Deposition plate. In other words, the results also indicated that water surface can absorb more ambient Dry Deposition inorganic pollutants than that of Dry Deposition plate in this study. The results obtained in this study indicated that the ionic species of Cl � ,N Oand SO 2� 4 occupied about average 60~70% downward flux out of total ionic species for either Dry Deposition plate or water surfaces sampler during August to October of 2006 at this near highway traffic sampling site.
Kazuo Asakura - One of the best experts on this subject based on the ideXlab platform.
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Atmospheric Dry Deposition of trace elements at a site on Asian-continent side of Japan
Atmospheric Environment, 2011Co-Authors: Masahiro Sakata, Kazuo AsakuraAbstract:The sources of Dry-deposited trace elements (As, Cd, Cr, Cu, Mn, Ni, Pb, Sb and V) and the factors controlling their Dry Deposition fluxes were investigated on the basis of two-year observations (April 2004–March 2006) at a site on the Asian-continent side of Japan, which has been strongly affected by air pollutants from the Asian continent. Dry Deposition sampling was conducted using a water surface sampler connected to a wet-only precipitation sampler. The Dry Deposition of As, Cd, Pb and Sb showed a small contribution to atmospheric Deposition (0.25–0.44 as ratios of annual Dry/wet Deposition fluxes). Moreover, the Dry Deposition fluxes of those elements increased negligibly during the period when their atmospheric particulate matter (PM) concentrations increased owing to transport from the Asian continent. Thus, the Dry Deposition of As, Cd, Pb and Sb from the Asian continent was not significant, because their overall Dry Deposition velocities are relatively low (mostly
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regional variations in wet and Dry Deposition fluxes of trace elements in japan
Atmospheric Environment, 2006Co-Authors: Masahiro Sakata, Kohji Marumoto, Masahiro Narukawa, Kazuo AsakuraAbstract:Abstract The annual wet and Dry Deposition fluxes of 12 trace elements (i.e., As, Cd, Cr, Cu, Hg, Mn, Mo, Ni, Pb, Sb, Se and V) were measured on the basis of 1 year of observations (December 2003–November 2004) at 10 sites in Japan. Precipitation and Dry Deposition (gases and particles) samples were collected every half month using an automatic sampler, which is composed of a precipitation sampler and a water surface sampler for Dry Deposition. The wet Deposition fluxes of Hg, Pb and Se exceeded their Dry Deposition fluxes at most sites. In contrast, the Dry Deposition fluxes of Cr, Cu, Mn, Mo, Ni and V were significantly higher than their wet Deposition fluxes. The annual wet Deposition fluxes of trace elements except for Cu, Mo and Ni were correlated with the annual precipitation amount ( P 0.05 ). In particular, about 70–80% of the variance of the wet Deposition fluxes for Hg ( r 2 = 0.80 ), Sb ( r 2 = 0.68 ) and V ( r 2 = 0.80 ) was explained using the precipitation amount. The wet Deposition fluxes of As, Cd, Pb and Se at sites on the Japan Sea coast tended to be higher than those expected from the precipitation amount. This suggests a large contribution of their long-range transport from the Asian continent. On the other hand, the regional variations in the Dry Deposition fluxes of the trace elements were different from those in the wet Deposition fluxes. A markedly higher Dry Deposition fluxes were observed at sites in industrial and urban areas. The relatively high Dry Deposition fluxes of Cr, Cu, Mn, Ni and Pb suggest that these elements are mainly from electric steel furnaces near the sites, because they are abundant in furnace emission particles. The results of lead isotope analyses indicate that the lead isotope ratios in the Dry Deposition samples at industrial and urban sites are different from those at other sites. This implies that lead Dry Deposition at such sites is dominated by emissions from peculiar sources, although whether those sources are the electric steel furnaces is unknown.
Caroline R Nowlan - One of the best experts on this subject based on the ideXlab platform.
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global Dry Deposition of nitrogen dioxide and sulfur dioxide inferred from space based measurements
Global Biogeochemical Cycles, 2014Co-Authors: Caroline R Nowlan, Randall V Martin, Sajeev Philip, Lok N Lamsal, Nickolay A Krotkov, Eloise A Marais, Siwen Wang, Qiang ZhangAbstract:A method is developed to estimate global NO2 and SO2 Dry Deposition fluxes at high spatial resolution (0.1°×0.1°) using satellite measurements from the Ozone Monitoring Instrument (OMI) on the Aura satellite, in combination with simulations from the Goddard Earth Observing System chemical transport model (GEOS-Chem). These global maps for 2005–2007 provide a data set for use in examining global and regional budgets of Deposition. In order to properly assess SO2 on a global scale, a method is developed to account for the geospatial character of background offsets in retrieved satellite columns. Globally, annual Dry Deposition to land estimated from OMI as NO2 contributes 1.5 ± 0.5 Tg of nitrogen and as SO2 contributes 13.7 ± 4.0 Tg of sulfur. Differences between OMI-inferred NO2 Dry Deposition fluxes and those of other models and observations vary from excellent agreement to an order of magnitude difference, with OMI typically on the low end of estimates. SO2 Dry Deposition fluxes compare well with in situ Clear Air Status and Trends Network-inferred flux over North America (slope = 0.98, r = 0.71). The most significant NO2 Dry Deposition flux to land per area occurs in the Pearl River Delta, China, at 13.9 kg N ha−1 yr−1, while SO2 Dry Deposition has a global maximum rate of 72.0 kg S ha−1 yr−1 to the east of Jinan in China's Shandong province. Dry Deposition fluxes are explored in several urban areas, where NO2 contributes on average 9–36% and as much as 85% of total NOy Dry Deposition.
