气候变化领域集成服务门户(CCPortal): Investigating the global OH radical distribution using steady-state approximations and satellite data

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DOI	10.5194/acp-22-10467-2022
	Investigating the global OH radical distribution using steady-state approximations and satellite data
	Pimlott, Matilda A.; Pope, Richard J.; Kerridge, Brian J.; Latter, Barry G.; Knappett, Diane S.; Heard, Dwayne E.; Ventress, Lucy J.; Siddans, Richard; Feng, Wuhu; Chipperfield, Martyn P.
发表日期	2022
ISSN	1680-7316
EISSN	1680-7324
起始页码	10467
结束页码	10488
卷号	22 期号:16 页码:22
英文摘要	We present a novel approach to derive indirect global information on the hydroxyl radical (OH), one of the most important atmospheric oxidants, using state-of-the-art satellite trace gas observations (key sinks and sources of OH) and a steady-state approximation (SSA). This is a timely study as OH observations are predominantly from spatially sparse field and infrequent aircraft campaigns, so there is a requirement for further approaches to infer spatial and temporal information on OH and its interactions with important climate (e.g. methane, CH4) and air quality (e.g. nitrogen dioxide, NO2) trace gases. Due to the short lifetime of OH (similar to 1 s), SSAs of varying complexities can be used to model its concentration and offer a tool to examine the OH budget in different regions of the atmosphere. Here, we use the well-evaluated TOMCAT three-dimensional chemistry transport model to identify atmospheric regions where different complexities of the SSAs are representative of OH. In the case of a simplified SSA (S-SSA), where we have observations of ozone (O-3), carbon monoxide (CO), CH4 and water vapour (H2O) from the Infrared Atmospheric Sounding Interferometer (IASI) on board ESA's MetOp-A satellite, it is most representative of OH between 600 and 700 hPa (though suitable between 400-800 hPa) within similar to 20 %-30 % of TOMCAT modelled OH. The same S-SSA is applied to aircraft measurements from the Atmospheric Tomography Mission (ATom) and compares well with the observed OH concentrations within similar to 26 %, yielding a correlation of 0.78. We apply the S-SSA to IASI data spanning 2008-2017 to explore the global long-term inter-annual variability of OH. Relative to the 10-year mean, we find that global annual mean OH anomalies ranged from -3.1 % to +4.7 %, with the largest spread in the tropics between -6.9 % and +7.7 %. Investigation of the individual terms in the S-SSA over this time period suggests that O-3 and CO were the key drivers of variability in the production and loss of OH. For example, large enhancement in the OH sink during the positive 2015/2016 El Nino-Southern Oscillation (ENSO) event was due to large-scale CO emissions from drought-induced wildfires in South East Asia. The methodology described here could be further developed as a constraint on the tropospheric OH distribution as additional satellite data become available in the future.
学科领域	Environmental Sciences; Meteorology & Atmospheric Sciences
语种	英语
WOS研究方向	Environmental Sciences & Ecology ; Meteorology & Atmospheric Sciences
WOS记录号	WOS:000841204100001
来源期刊	ATMOSPHERIC CHEMISTRY AND PHYSICS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/273520
作者单位	University of Leeds; University of Leeds; UK Research & Innovation (UKRI); Science & Technology Facilities Council (STFC); STFC Rutherford Appleton Laboratory; UK Research & Innovation (UKRI); Science & Technology Facilities Council (STFC); STFC Rutherford Appleton Laboratory; University of Leeds; UK Research & Innovation (UKRI); Natural Environment Research Council (NERC); NERC National Centre for Atmospheric Science; University of Leeds
推荐引用方式 GB/T 7714	Pimlott, Matilda A.,Pope, Richard J.,Kerridge, Brian J.,et al. Investigating the global OH radical distribution using steady-state approximations and satellite data[J],2022,22(16):22.
APA	Pimlott, Matilda A..,Pope, Richard J..,Kerridge, Brian J..,Latter, Barry G..,Knappett, Diane S..,...&Chipperfield, Martyn P..(2022).Investigating the global OH radical distribution using steady-state approximations and satellite data.ATMOSPHERIC CHEMISTRY AND PHYSICS,22(16),22.
MLA	Pimlott, Matilda A.,et al."Investigating the global OH radical distribution using steady-state approximations and satellite data".ATMOSPHERIC CHEMISTRY AND PHYSICS 22.16(2022):22.