气候变化领域集成服务门户(CCPortal): The effect of atmospheric nudging on the stratospheric residual circulation in chemistry-climate models

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DOI	10.5194/acp-19-11559-2019
	The effect of atmospheric nudging on the stratospheric residual circulation in chemistry-climate models
	Chrysanthou A.; Maycock A.C.; Chipperfield M.P.; Dhomse S.; Garny H.; Kinnison D.; Akiyoshi H.; Deushi M.; Garcia R.R.; Jöckel P.; Kirner O.; Pitari G.; Plummer D.A.; Revell L.; Rozanov E.; Stenke A.; Tanaka T.Y.; Visioni D.; Yamashita Y.
发表日期	2019
ISSN	16807316
起始页码	11559
结束页码	11586
卷号	19 期号:17
英文摘要	We perform the first multi-model intercomparison of the impact of nudged meteorology on the stratospheric residual circulation using hindcast simulations from the Chemistry-Climate Model Initiative (CCMI). We examine simulations over the period 1980-2009 from seven models in which the meteorological fields are nudged towards a reanalysis dataset and compare these with their equivalent free-running simulations and the reanalyses themselves. We show that for the current implementations, nudging meteorology does not constrain the mean strength of the stratospheric residual circulation and that the inter-model spread is similar, or even larger, than in the free-running simulations. The nudged models generally show slightly stronger upwelling in the tropical lower stratosphere compared to the free-running versions and exhibit marked differences compared to the directly estimated residual circulation from the reanalysis dataset they are nudged towards. Downward control calculations applied to the nudged simulations reveal substantial differences between the climatological lowerstratospheric tropical upward mass flux (TUMF) computed from the modelled wave forcing and that calculated directly from the residual circulation. This explicitly shows that nudging decouples the wave forcing and the residual circulation so that the divergence of the angular momentum flux due to the mean motion is not balanced by eddy motions, as would typically be expected in the time mean. Overall, nudging meteorological fields leads to increased intermodel spread for most of the measures of the mean climatological stratospheric residual circulation assessed in this study. In contrast, the nudged simulations show a high degree of consistency in the inter-Annual variability in the TUMF in the lower stratosphere, which is primarily related to the contribution to variability from the resolved wave forcing. The more consistent inter-Annual variability in TUMF in the nudged models also compares more closely with the variability found in the reanalyses, particularly in boreal winter. We apply a multiple linear regression (MLR) model to separate the drivers of inter-Annual and long-Term variations in the simulated TUMF; this explains up to 75% of the variance in TUMF in the nudged simulations. The MLR model reveals a statistically significant positive trend in TUMF for most models over the period 1980-2009. The TUMF trend magnitude is generally larger in the nudged models compared to their free-running counterparts, but the intermodel range of trends doubles from around a factor of 2 to a factor of 4 due to nudging. Furthermore, the nudged models generally do not match the TUMF trends in the reanalysis they are nudged towards for trends over different periods in the interval 1980-2009. Hence, we conclude that nudging does not strongly constrain long-Term trends simulated by the chemistry-climate model (CCM) in the residual circulation. Our findings show that while nudged simulations may, by construction, produce accurate temperatures and realistic representations of fast horizontal transport, this is not typically the case for the slower zonal mean vertical transport in the stratosphere. Consequently, caution is required when using nudged simulations to interpret the behaviour of stratospheric tracers that are affected by the residual circulation. © Author(s) 2019.
语种	英语
scopus关键词	annual variation; atmospheric chemistry; atmospheric circulation; climate modeling; meteorology; stratosphere; wave force
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/144151
作者单位	School of Earth and Environment, University of Leeds, Leeds, United Kingdom; Institut für Physik der Atmosphäre, Deutsches Zentrum für Luft-und Raumfahrt (DLR), Oberpfaffenhofen, Germany; Meteorological Institute Munich, Ludwig Maximilian University of Munich, Munich, Germany; National Center for Atmospheric Research (NCAR), Boulder, CO, United States; National Institute for Environmental Studies (NIES), Tsukuba, Japan; Meteorological Research Institute (MRI), Tsukuba, Japan; Steinbuch Centre for Computing, Karlsruhe Institute of Technology, Karlsruhe, Germany; Department of Physical and Chemical Sciences, Università dell'Aquila, L'Aquila, Italy; Climate Research Division, Environment and Climate Change Canada, Montréal, QC, Canada; School of Physical and Chemical Sciences, University of Canterbury, Christchurch, New Zealand; Institute for Atmospheric and Climate Science, ETH Zürich (ETHZ), Zurich, Switzerland; Physical-Meteorological Observatory/World Radiation Center, Davos, Switzerland; Sibley School o...
推荐引用方式 GB/T 7714	Chrysanthou A.,Maycock A.C.,Chipperfield M.P.,et al. The effect of atmospheric nudging on the stratospheric residual circulation in chemistry-climate models[J],2019,19(17).
APA	Chrysanthou A..,Maycock A.C..,Chipperfield M.P..,Dhomse S..,Garny H..,...&Yamashita Y..(2019).The effect of atmospheric nudging on the stratospheric residual circulation in chemistry-climate models.Atmospheric Chemistry and Physics,19(17).
MLA	Chrysanthou A.,et al."The effect of atmospheric nudging on the stratospheric residual circulation in chemistry-climate models".Atmospheric Chemistry and Physics 19.17(2019).