气候变化领域集成服务门户(CCPortal): A Lagrangian Perspective on Stable Water Isotopes During the West African Monsoon

CCPortal

DOI	10.1029/2021JD034895
	A Lagrangian Perspective on Stable Water Isotopes During the West African Monsoon
	Diekmann C.J.; Schneider M.; Knippertz P.; de Vries A.J.; Pfahl S.; Aemisegger F.; Dahinden F.; Ertl B.; Khosrawi F.; Wernli H.; Braesicke P.
发表日期	2021
ISSN	2169-897X
卷号	126 期号:19
英文摘要	We present a Lagrangian framework for identifying mechanisms that control the isotopic composition of mid-tropospheric water vapor in the Sahel region during the West African Monsoon 2016. In this region mixing between contrasting air masses, strong convective activity, as well as surface and rain evaporation lead to high variability in the distribution of stable water isotopologues. Using backward trajectories based on high-resolution isotope-enabled model data, we obtain information not only about the source regions of Sahelian air masses, but also about the evolution of (Formula presented.) O and its isotopologue HDO (expressed as (Formula presented.) D) along the pathways of individual air parcels. We sort the full trajectory ensemble into groups with similar transport pathways and hydro-meteorological properties, such as precipitation and relative humidity, and investigate the evolution of the corresponding paired { (Formula presented.) O, (Formula presented.) } distributions. The use of idealized process curves in the { (Formula presented.) O, (Formula presented.) } phase space allows us to attribute isotopic changes to contributions from (a) air mass mixing, (b) Rayleigh condensation during convection, and (c) microphysical processes depleting the vapor beyond the Rayleigh prediction, i.e., partial rain evaporation in unsaturated and isotopic equilibration in saturated conditions. Different combinations of these processes along the trajectory ensembles are found to determine the final isotopic composition in the Sahelian troposphere during the monsoon. The presented Lagrangian framework is a powerful tool for interpreting tropospheric water vapor distributions. In the future, it will be applied to satellite observations of { (Formula presented.) O, (Formula presented.) } over Africa and other regions in order to better quantify characteristics of the hydrological cycle. © 2021. The Authors.
英文关键词	air mass mixing; Lagrangian trajectories; rain interaction; stable water isotopes; West African Monsoon
来源期刊	Journal of Geophysical Research: Atmospheres
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/236980
作者单位	Institute for Meteorology and Climate Research, Karlsruhe Institute of Technology, Karlsruhe, Germany; Institute for Atmospheric and Climate Science, ETH Zurich, Zurich, Switzerland; Institute of Meteorology, Freie Universität Berlin, Berlin, Germany; Steinbuch Centre for Computing, Karlsruhe Institute of Technology, Karlsruhe, Germany
推荐引用方式 GB/T 7714	Diekmann C.J.,Schneider M.,Knippertz P.,et al. A Lagrangian Perspective on Stable Water Isotopes During the West African Monsoon[J],2021,126(19).
APA	Diekmann C.J..,Schneider M..,Knippertz P..,de Vries A.J..,Pfahl S..,...&Braesicke P..(2021).A Lagrangian Perspective on Stable Water Isotopes During the West African Monsoon.Journal of Geophysical Research: Atmospheres,126(19).
MLA	Diekmann C.J.,et al."A Lagrangian Perspective on Stable Water Isotopes During the West African Monsoon".Journal of Geophysical Research: Atmospheres 126.19(2021).