气候变化领域集成服务门户(CCPortal): Influences of oceanic ozone deposition on tropospheric photochemistry

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DOI	10.5194/acp-20-4227-2020
	Influences of oceanic ozone deposition on tropospheric photochemistry
	Pound R.J.; Sherwen T.; Helmig D.; Carpenter L.J.; Evans M.J.
发表日期	2020
ISSN	16807316
起始页码	4227
结束页码	4239
卷号	20 期号:7
英文摘要	The deposition of ozone to seawater is an important ozone sink. Despite constituting as much as a third of the total ozone deposition, it receives significantly less attention than the deposition to terrestrial ecosystems. Models have typically calculated the deposition rate based on a resistance-in-series model with a uniform waterside resistance. This leads to models having an essentially uniform deposition velocity of approximately 0.05 cm s-1 to seawater, which is significantly higher than the limited observational dataset. Following from Luhar et al. (2018) we include a representation of the oceanic deposition of ozone in the GEOS-Chem model of atmospheric chemistry and transport based on its reaction with sea-surface iodide. The updated scheme halves the calculated annual area-weighted mean deposition velocity to water from 0.0464 cm s-1 (25th and 75th percentiles of 0.0461 cm s-1 and 0.0471 cm s-1 respectively) to 0.0231 cm s-1 (25th and 75th percentiles of 0.0121 cm s-1 and 0.0303 cm s-1 respectively). The calculated ozone deposition velocity varies from 0.009 cm s-1 in polar waters to 0.040 cm s-1 at the tropics. This improves comparisons to observations. The variability is driven mainly by the temperature-dependent rate constant for the reaction between iodide and ozone, the temperature dependence of the solubility, and variations in the ocean iodide concentration. The calculated annual deposition flux of ozone to the ocean is reduced from 222 to 122 Tg yr-1, and overall deposition of ozone to all surface types reduces from 862 to 758 Tg yr-1. Tropospheric ozone burdens and global mean OH increase from 324 to 328 Tg, and from 1.17×106 to 1.18×106 molec.cm-3, respectively. A total of 34 % of surface grid boxes experience a 10 % or greater increase in ozone concentration. Comparisons between observations of surface ozone and the model are improved with the new parameterization notably around the Southern Ocean. Process-level representation of oceanic deposition of ozone thus appears essential for representing the concentration of surface ozone over the planet. © 2020 Author(s).
关键词	atmospheric chemistry atmospheric deposition atmospheric pollution atmospheric transport concentration (composition)GOES iodide ozone photochemistry pollutant transport sea surface source-sink dynamics troposphere Southern Ocean
语种	英语
来源机构	Atmospheric Chemistry and Physics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/132109
推荐引用方式 GB/T 7714	Pound R.J.,Sherwen T.,Helmig D.,et al. Influences of oceanic ozone deposition on tropospheric photochemistry[J]. Atmospheric Chemistry and Physics,2020,20(7).
APA	Pound R.J.,Sherwen T.,Helmig D.,Carpenter L.J.,&Evans M.J..(2020).Influences of oceanic ozone deposition on tropospheric photochemistry.,20(7).
MLA	Pound R.J.,et al."Influences of oceanic ozone deposition on tropospheric photochemistry".20.7(2020).