Measuring metallic elements of total suspended particulates (TSPs), dry deposition flux, and dry deposition velocity for seasonal variation in central Taiwan

The main purpose for this study was to monitor ambient air particles and metallic elements (Mn, Fe, Zn, Cr, and Cu) in total suspended particulates (TSPs) concentration, dry deposition at three characteristic sampling sites of central Taiwan. Additionally, the calculated/measured dry deposition flux ratios of ambient air particles and metallic elements were calculated with Woods models at these three characteristic sampling sites during years of 2009-2010. As for ambient air particles, the results indicated that the Woods model generated the most accurate dry deposition prediction results when particle size was 18 μm in this study. The results also indicated that the Woods model exhibited better dry deposition prediction performance when the particle size was greater than 10 μm for the ambient air metallic elements in this study. Finally, as for Quan-xing sampling site, the main sources were many industrial factories under process around these regions and were severely polluted areas. In addition, the highest average dry deposition for Mn, Fe, Zn, and Cu species occurred at Bei-shi sampling site, and the main sources were the nearby science park, fossil fuel combustion, and Taichung thermal power plant (TTPP). Additionally, as for He-mei sampling site, the main sources were subjected to traffic mobile emissions.

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Aerosol acidity as a driver of aerosol formation and nutrient deposition to ecosystems

10.5194/egusphere-egu2020-21227 ◽

2020 ◽

Author(s):

Athanasios Nenes ◽

Maria Kanakidou ◽

Spyros Pandis ◽

Armistead Russell ◽

Shaojie Song ◽

...

Keyword(s):

Boundary Layer ◽

Particulate Matter ◽

Dry Deposition ◽

Deposition Velocity ◽

Liquid Water Content ◽

Reactive Nitrogen ◽

Deposition Flux ◽

Deposition Rates ◽

Dry Deposition Flux ◽

Nitrate Aerosol

Nitrogen oxides (NOx) and ammonia (NH3) from anthropogenic and biogenic emissions are central contributors to particulate matter (PM) concentrations worldwide. Ecosystem productivity can also be strongly modulated by the atmospheric deposition of this inorganic "reactive nitrogen" nutrient. The response of PM and nitrogen deposition to changes in the emissions of both compounds is typically studied on a case-by-case basis, owing in part to the complex thermodynamic interactions of these aerosol precursors with other PM constituents. In the absence of rain, much of the complexity of nitrogen deposition is driven by the large difference in dry deposition velocity when a nitrogen-containing molecule is in the gas or condensed phase.Here we present a simple but thermodynamically consistent approach that expresses the chemical domains of sensitivity of aerosol particulate matter to NH3 and HNO3 availability in terms of aerosol pH and liquid water content. From our analysis, four policy-relevant regimes emerge in terms of sensitivity: i) NH3-sensitive, ii) HNO3-sensitive, iii) combined NH3 and HNO3 sensitive, and, iv) a domain where neither NH3 and HNO3 are important for PM levels (but only nonvolatile precursors such as NVCs and sulfate). When this framework is applied to ambient measurements or predictions of PM and gaseous precursors, the &#8220;chemical regime&#8221; of PM sensitivity to NH3 and HNO3 availability is directly determined.&#160;The same framework is then extended to consider the impact of gas-to-particle partitioning, on the deposition velocity of NH3 and HNO3 individually, and combined affects the dry deposition of inorganic reactive nitrogen. Four regimes of deposition velocity emerge: i) HNO3-fast, NH3-slow, ii) HNO3-slow, NH3-fast, iii) HNO3-fast, NH3-fast, and, iv) HNO3-slow, NH3-slow. Conditions that favor strong partitioning of species to the aerosol phase strongly delay the deposition of reactive nitrogen species and promotes their accumulation in the boundary layer and potential for long-range transport.&#160;The use of these regimes allows novel insights and is an important tool to evaluate chemical transport models. Most notably, we find that nitric acid displays considerable variability of dry deposition flux, with maximum deposition rates found in the Eastern US (close to gas-deposition rates) and minimum rates for North Europe and China. Strong reductions in deposition velocity lead to considerable accumulation of nitrate aerosol in the boundary layer &#8211;up to 10-fold increases in PM2.5 nitrate aerosol, eventually being an important contributor to high PM2.5 levels observed during haze episodes. With this new understanding, aerosol pH and associated liquid water content can be understood as control parameters that drive PM formation and dry deposition flux and arguably can catalyze the accumulation of aerosol precursors that cause intense haze events throughout the globe.

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Study of Ambient Air Particle-Bound As(p) and Hg(p) in Dry Deposition, Total Suspended Particulates (TSP) and Seasonal Variations in Central Taiwan

Environmental Forensics ◽

10.1080/15275922.2010.547550 ◽

2011 ◽

Vol 12 (1) ◽

pp. 7-13 ◽

Cited By ~ 14

Author(s):

Guor-Cheng Fang ◽

Winn-Jung Huang ◽

Jyh-Cherng Chen ◽

Jun-Han Huang ◽

Yi-Liang Huang

Keyword(s):

Seasonal Variations ◽

Dry Deposition ◽

Ambient Air ◽

Suspended Particulates ◽

Total Suspended Particulates ◽

Central Taiwan

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Measurement of Atmospheric Dry Deposition Flux and Resultant Deposition Velocity of Inorganic Pollutants in the Provincial Capital of Punjab, Pakistan

Environmental Forensics ◽

10.1080/15275920802501770 ◽

2008 ◽

Vol 9 (4) ◽

pp. 290-294 ◽

Cited By ~ 2

Author(s):

S. N. A. Tahir ◽

Sahibzad Khan

Keyword(s):

Dry Deposition ◽

Deposition Velocity ◽

Deposition Flux ◽

Inorganic Pollutants ◽

Dry Deposition Flux ◽

Provincial Capital

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The concentration, dry deposition, composition study of ambient air particulate and metallic pollutants at a traffic sampling site

Toxicology and Industrial Health ◽

10.1191/0748233703th170oa ◽

2003 ◽

Vol 19 (1) ◽

pp. 25-35 ◽

Cited By ~ 3

Author(s):

Guor-Cheng Fang ◽

Yuh-Shen Wu ◽

Chia-Chium Chu ◽

Shih-Han Huang ◽

Jui-Yeh Rau

Keyword(s):

Dry Deposition ◽

Deposition Velocity ◽

Sampling Site ◽

Ambient Air ◽

Metallic Elements ◽

Night Time ◽

Deposition Fluxes ◽

Air Particulate ◽

Time Period ◽

Central Taiwan

Aerosol samples were collected by total suspended particulate (TSP) and dry deposition plate (downward, upward) from August to November in 2003 in central Taiwan. The particulate metallic elements (Fe, Pb, Zn, Cu, Mg and Mn) were also measured in this study during the summer and autumn periods of 2003. The results obtained in this study indicated that the ambient air particulate mass concentrations in the daytime period (averaged 975.4 mg/m3) were higher than the night-time period (averaged 542.1 mg/m3). And the downward dry deposition fluxes (averaged 58.12 mg/m2-sec) were about 2.2 times that of upward dry deposition fluxes (averaged 26.37 mg/m2-sec) in the daytime period. Furthermore, the average downward dry deposition fluxes (averaged 26.54 mg/m2-sec) were also about 2.3 times that of upward dry deposition fluxes (averaged 11.52 mg/m2-sec) in the nighttime period. Moreover, the average downward dry deposition fluxes are greater than the upward dry deposition fluxes for all the heavy metals in either daytime or night-time period. In addition, the deposition velocity for mass, metallic elements (Fe, Pb, Zn, Cu, Mg and Mn) during daytime and night-time period were also calculated. In addition, the average TSP composition (mg/g) in the daytime period of the metallic elements (Fe, Pb, Zn, Cu, Mg and Mn) is 1.73, 0.26, 1.16, 0.28, 0.43 and 0.12 mg/g, respectively. And the average TSP composition in the night-time period of the metallic elements (Fe, Pb, Zn, Cu, Mg and Mn) is 3.02, 0.33, 1.57, 0.41, 0.58 and 0.13 mg/g, respectively at traffic sampling site of central Taiwan.

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Observation of SO2 dry deposition velocity at a high elevation flux tower over an evergreen broadleaf forest in Central Taiwan

Atmospheric Environment ◽

10.1016/j.atmosenv.2009.12.022 ◽

2010 ◽

Vol 44 (8) ◽

pp. 1011-1019 ◽

Cited By ~ 13

Author(s):

Jeng-Lin Tsai ◽

Chien-Lung Chen ◽

Ben-Jei Tsuang ◽

Pei-Hsuan Kuo ◽

Kuo-Hsin Tseng ◽

...

Keyword(s):

Dry Deposition ◽

Deposition Velocity ◽

High Elevation ◽

Broadleaf Forest ◽

Flux Tower ◽

Dry Deposition Velocity ◽

Central Taiwan ◽

So2 Dry Deposition

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Seasonal variation in concentration and metallic constituents of atmospheric particulates near the western coast of central Taiwan

Toxicology and Industrial Health ◽

10.1191/0748233706th262oa ◽

2006 ◽

Vol 22 (5) ◽

pp. 193-201 ◽

Cited By ~ 1

Author(s):

Guor-Cheng Fang ◽

Yuh-Shen Wu ◽

Wen-Jhy Lee ◽

Te-Yen Chou ◽

I-Chen Lin

Keyword(s):

Fine Particles ◽

Western Coast ◽

Metallic Elements ◽

High Concentration ◽

Fine Particulates ◽

Atmospheric Particulates ◽

Suspended Particulates ◽

Total Suspended Particulates ◽

Coarse Particulates ◽

Central Taiwan

In addition to determining the concentration and metallic constituents of particulate matter at Taichung Harbor in central Taiwan, this study attempts to characterize the mass, metallic elements, composition and concentrations of total suspended particulates (TSP), fine particles and coarse particles. Statistical approaches, such as the Spearman tests, were also adopted to determine the seasonal variations of concentrations of these pollutants. Experimental results indicate that the mean TSP, fine particulate and coarse particulate concentrations in spring and winter are higher than in summer and autumn on the western coast of central Taiwan. Spearman statistical analysis of metallic elements Mn and Pb showed high concentration coefficients for fine and coarse particulates on the western coast of central Taiwan. The order of mean metallic concentrations in TSP, coarse particulates and fine particles was Fe-Zn-Mg-Cu-Cr-Mn-Pb in TSP, Fe-Cu-Zn-Mg-Mn-Pb-Cr in coarse particulates and Fe-Cu-Mg-Pb-Zn-Mn-Cr in fine particulates.

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