气候变化领域集成服务门户(CCPortal): Siberian snow forcing in a dynamically bias-corrected model

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DOI	10.1175/JCLI-D-20-0459.1
	Siberian snow forcing in a dynamically bias-corrected model
	Tyrrell N.L.; Karpechko A.Y.U.; Rast S.
发表日期	2020
ISSN	0894-8755
起始页码	10455
结束页码	10467
卷号	33 期号:24
英文摘要	We investigate the effect of systematic model biases on teleconnections influencing the Northern Hemisphere wintertime circulation. We perform a two-step nudging and bias-correcting scheme for the dynamic variables of the ECHAM6 atmospheric model to reduce errors in the model climatology relative to ERA-Interim. One result is a significant increase in the strength of the Northern Hemisphere wintertime stratospheric polar vortex, reducing errors in the December-February mean zonal stratospheric winds by up to 75%. The bias corrections are applied to the full atmosphere or the stratosphere only. We compare the response of the bias-corrected and control runs to an increase in Siberian snow cover in October-a surface forcing that, in our experiments, weakens the stratospheric polar vortex from October to December. We find that despite large differences in the vortex strength the magnitude of the stratospheric weakening is similar among the different climatologies, with some differences in the timing and length of the response. Differences are more pronounced in the stratosphere-troposphere coupling, and the subsequent surface response. The snow forcing with the stratosphere-only bias corrections results in a stratospheric response that is comparable to control, yet with an enhanced surface response that extends into early January. The full-atmosphere bias correction's snow response also has a comparable stratospheric response but a somewhat suppressed surface response. Despite these differences, our results show an overall small sensitivity of the Eurasian snow teleconnection to the background climatology. © 2020 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).
英文关键词	Climatology; Vortex flow; Atmospheric model; Dynamic variables; Model climatology; Northern Hemispheres; Stratosphere-troposphere coupling; Stratospheric polar vortex; Stratospheric winds; Systematic modeling; Snow; atmospheric circulation; climate modeling; Northern Hemisphere; polar vortex; snow; stratosphere-troposphere interaction; teleconnection
语种	英语
来源期刊	Journal of Climate
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/171520
作者单位	Finnish Meteorological Institute, Helsinki, Finland; Max Planck Institute for Meteorology, Hamburg, Germany
推荐引用方式 GB/T 7714	Tyrrell N.L.,Karpechko A.Y.U.,Rast S.. Siberian snow forcing in a dynamically bias-corrected model[J],2020,33(24).
APA	Tyrrell N.L.,Karpechko A.Y.U.,&Rast S..(2020).Siberian snow forcing in a dynamically bias-corrected model.Journal of Climate,33(24).
MLA	Tyrrell N.L.,et al."Siberian snow forcing in a dynamically bias-corrected model".Journal of Climate 33.24(2020).