气候变化领域集成服务门户(CCPortal): Technical note: Lowermost-stratosphere moist bias in ECMWF IFS model diagnosed from airborne GLORIA observations during winter-spring 2016

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DOI	10.5194/acp-20-15379-2020
	Technical note: Lowermost-stratosphere moist bias in ECMWF IFS model diagnosed from airborne GLORIA observations during winter-spring 2016
	Woiwode W.; Dörnbrack A.; Polichtchouk I.; Dornbrack A.; Harvey B.; Höpfner M.; Ungermann J.; Friedl-Vallon F.
发表日期	2020
ISSN	1680-7316
起始页码	15379
结束页码	15387
卷号	20 期号:23
英文摘要	Numerical weather forecast systems like the ECMWF IFS (European Centre for Medium-Range Weather Forecasts-Integrated Forecasting System) are known to be affected by a moist bias in the extratropical lowermost stratosphere (LMS) which results in a systematic cold bias there. We use high-spatial-resolution water vapor measurements by the airborne infrared limb-imager GLORIA (Gimballed Limb Observer for Radiance Imaging of the Atmosphere) during the PGS (POLSTRACC/GW-LCYCLE-II/SALSA) campaign to study the LMS moist bias in ECMWF analyses and 12 h forecasts from January to March 2016. Thereby, we exploit the two-dimensional observational capabilities of GLORIA, when compared to in situ observations, and the higher vertical and horizontal resolution, when compared to satellite observations. Using GLORIA observations taken during five flights in the polar sub-vortex region around Scandinavia and Greenland, we diagnose a systematic moist bias in the LMS exceeding C50% (January) to C30% (March) at potential vorticity levels from 10 PVU (highest level accessed with suitable coverage) to 7 PVU. In the diagnosed time period, the moist bias decreases at the highest and driest air masses observed but clearly persists at lower levels until mid-March. Sensitivity experiments with more frequent temporal output, and lower or higher horizontal and vertical resolution, show the short-term forecasts to be practically insensitive to these parameters on timescales of <12 h. Our results confirm that the diagnosed moist bias is already present in the initial conditions (i.e., the analysis) and thus support the hypothesis that the cold bias develops as a result of forecast initialization. The moist bias in the analysis might be explained by a model bias together with the lack of water vapor observations suitable for assimilation above the tropopause. © 2020 BMJ Publishing Group. All rights reserved.
语种	英语
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/247279
作者单位	Institute of Meteorology and Climate Research (IMK), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany; Deutsches Zentrum für Luft-und Raumfahrt, Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany; European Centre for Medium-Range Weather Forecasts, Reading, United Kingdom; National Centre for Atmospheric Science, University of Reading, Reading, United Kingdom; Institute of Energy and Climate Research-Stratosphere (IEK-7), Forschungszentrum Jülich, Jülich, Germany
推荐引用方式 GB/T 7714	Woiwode W.,Dörnbrack A.,Polichtchouk I.,et al. Technical note: Lowermost-stratosphere moist bias in ECMWF IFS model diagnosed from airborne GLORIA observations during winter-spring 2016[J],2020,20(23).
APA	Woiwode W..,Dörnbrack A..,Polichtchouk I..,Dornbrack A..,Harvey B..,...&Friedl-Vallon F..(2020).Technical note: Lowermost-stratosphere moist bias in ECMWF IFS model diagnosed from airborne GLORIA observations during winter-spring 2016.ATMOSPHERIC CHEMISTRY AND PHYSICS,20(23).
MLA	Woiwode W.,et al."Technical note: Lowermost-stratosphere moist bias in ECMWF IFS model diagnosed from airborne GLORIA observations during winter-spring 2016".ATMOSPHERIC CHEMISTRY AND PHYSICS 20.23(2020).