气候变化领域集成服务门户(CCPortal): Convective hydration in the tropical tropopause layer during the StratoClim aircraft campaign: Pathway of an observed hydration patch

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DOI	10.5194/acp-19-11803-2019
	Convective hydration in the tropical tropopause layer during the StratoClim aircraft campaign: Pathway of an observed hydration patch
	Lee K.-O.; Dauhut T.; Chaboureau J.-P.; Khaykin S.; Krämer M.; Rolf C.
发表日期	2019
ISSN	16807316
起始页码	11803
结束页码	11820
卷号	19 期号:18
英文摘要	The source and pathway of the hydration patch in the TTL (tropical tropopause layer) that was measured during the Stratospheric and upper tropospheric processes for better climate predictions (StratoClim) field campaign during the Asian summer monsoon in 2017 and its connection to convective overshoots are investigated. During flight no. 7, two remarkable layers are measured in the TTL, namely (1) the moist layer (ML) with a water vapour content of 4.8-5.7ppmv in altitudes of 18-19km in the lower stratosphere and (2) the ice layer (IL) with ice content up to 1.9eq.ppmv (equivalent parts per million by volume) in altitudes of 17-18km in the upper troposphere at around 06:30UTC on 8 August to the south of Kathmandu (Nepal). A Meso-NH convection-permitting simulation succeeds in reproducing the characteristics of the ML and IL. Through analysis, we show that the ML and IL are generated by convective overshoots that occurred over the Sichuan Basin about 1.5d before. Overshooting clouds develop at altitudes up to 19km, hydrating the lower stratosphere of up to 20km with 6401t of water vapour by a strong-to-moderate mixing of the updraughts with the stratospheric air. A few hours after the initial overshooting phase, a hydration patch is generated, and a large amount of water vapour (above 18ppmv) remains at even higher altitudes up to 20.5km while the anvil cloud top descends to 18.5km. At the same time, a great part of the hydrometeors falls shortly, and the water vapour concentration in the ML and IL decreases due to turbulent diffusion by mixing with the tropospheric air, ice nucleation, and water vapour deposition. As the hydration patch continues to travel toward the south of Kathmandu, tropospheric tracer concentration increases up to 30% and 70% in the ML and IL, respectively. The air mass in the layers becomes gradually diffused, and it has less and less water vapour and ice content by mixing with the dry tropospheric air. © Author(s) 2019.
语种	英语
scopus关键词	air mass; airborne survey; atmospheric convection; climate prediction; concentration (composition); hydration; monsoon; stratosphere-troposphere interaction; tropopause; water vapor; Bagmati; China; Kathmandu; Nepal; Sichuan Basin
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/144141
作者单位	Laboratoire d'Aérologie, Université de Toulouse, CNRS, UPS, Toulouse, France; LATMOS/IPSL, UVSQ, Sorbonne Université, CNRS, Guyancourt, France; Institute for Energy and Climate Research - Stratosphere (IEK-7), Forschungzentrum Jülich, Jülich, Germany; Institute für Atmospheric Physics, Johannes Gutenberg-Universität Mainz, Mainz, Germany
推荐引用方式 GB/T 7714	Lee K.-O.,Dauhut T.,Chaboureau J.-P.,et al. Convective hydration in the tropical tropopause layer during the StratoClim aircraft campaign: Pathway of an observed hydration patch[J],2019,19(18).
APA	Lee K.-O.,Dauhut T.,Chaboureau J.-P.,Khaykin S.,Krämer M.,&Rolf C..(2019).Convective hydration in the tropical tropopause layer during the StratoClim aircraft campaign: Pathway of an observed hydration patch.Atmospheric Chemistry and Physics,19(18).
MLA	Lee K.-O.,et al."Convective hydration in the tropical tropopause layer during the StratoClim aircraft campaign: Pathway of an observed hydration patch".Atmospheric Chemistry and Physics 19.18(2019).