气候变化领域集成服务门户(CCPortal): A comparison of two bidirectional air-surface exchange models for gaseous elemental mercury over vegetated surfaces

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DOI	10.1016/j.atmosenv.2020.118096
	A comparison of two bidirectional air-surface exchange models for gaseous elemental mercury over vegetated surfaces
	Hao J.; Xu X.; Lin C.-J.; Zhang L.
发表日期	2021
ISSN	1352-2310
卷号	246
英文摘要	Uncertainties exist in the current estimates of atmospheric dry deposition and air-surface exchange of atmospheric mercury in chemical transport models and monitoring networks. To quantitatively assess these uncertainties, two bidirectional air-surface exchange models for gaseous elemental mercury (Hg0), originally developed by Wang et al. (2014, Atmos. Chem. Phys., doi:10.5194/acp-14-6273-2014) and Wright and Zhang (2015, J. Adv. Model. Earth Syst., doi:10.1002/2014MS000367), were compared quantitatively. The two models were applied to two vegetated land covers, including a deciduous broadleaf forest and a cropland, near a monitoring site in Georgia, USA for calculating air-surface exchange fluxes of Hg0. The model inputs include measured 2-hourly ambient Hg0 concentrations and archived surface meteorology data produced from a weather forecast model. The estimated annual net fluxes differed significantly between the two models, i.e., −0.7 μg m−2yr−1 by Wang et al.’s model vs. −8.6 μg m−2yr−1 by Wright & Zhang's model over the deciduous broadleaf forest and 8.4 μg m−2yr−1 vs. −10.7 μg m−2yr−1 over the cropland. When considering dry deposition and emission fluxes separately, similar deposition fluxes were produced by the two models, regardless of season and land cover, due to the similar canopy resistance formulas used in the two models. Much higher soil and lower stomatal emission fluxes were produced by Wang et al.’s model than Wright & Zhang's model (soil: 30 vs. 8.9 μg m−2yr−1 and stomata: 0.5 vs. 8.3 μg m−2yr−1, averaged over the two canopies) due to the very different emission potentials used in the two models. Cuticle emission fluxes contributed less than 0.1% to the total emission flux in Wang et al.’s model, and were not considered in Wright & Zhang's model. The differences in soil emission flux, total emission flux, and net flux were more pronounced in winter than in the other seasons. The large differences in the net fluxes between the two models were primarily caused by their very different schemes of soil emission potential. © 2020 Elsevier Ltd
英文关键词	Atmospheric chemistry; Atmospheric movements; Deposition; Forestry; Soils; Uncertainty analysis; Air-surface exchanges; Atmospheric dry deposition; Atmospheric mercury; Chemical transport models; Emission potential; Gaseous elemental mercury; Monitoring network; Weather forecast models; Weather forecasting; mercury; organic carbon; water; air sampling; air-soil interaction; atmospheric modeling; chemical pollutant; comparative study; deciduous forest; dry deposition; land cover; mercury (element); pollution monitoring; soil emission; air; Article; autumn; canopy; compensation; controlled study; cropland; diffusion; environmental temperature; forest; land use; leaf area; meteorology; net flux; priority journal; seasonal variation; soil; spring; summer; temperature; weather; wind speed; winter; Georgia; United States
语种	英语
来源期刊	Atmospheric Environment
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/169067
作者单位	Department of Civil and Environmental Engineering, University of Windsor, 401 Sunset Avenue, Windsor, ON N9B 3P4, Canada; Department of Civil and Environmental Engineering, Lamar University, Beaumont, TX 77705, United States; Air Quality Research Division, Science and Technology Branch, Environment and Climate Change Canada, Toronto, ON M3H 5T4, Canada
推荐引用方式 GB/T 7714	Hao J.,Xu X.,Lin C.-J.,et al. A comparison of two bidirectional air-surface exchange models for gaseous elemental mercury over vegetated surfaces[J],2021,246.
APA	Hao J.,Xu X.,Lin C.-J.,&Zhang L..(2021).A comparison of two bidirectional air-surface exchange models for gaseous elemental mercury over vegetated surfaces.Atmospheric Environment,246.
MLA	Hao J.,et al."A comparison of two bidirectional air-surface exchange models for gaseous elemental mercury over vegetated surfaces".Atmospheric Environment 246(2021).