气候变化领域集成服务门户(CCPortal): North pacific upper-ocean cold temperature biases in CMIP6 simulations and the role of regional vertical mixing

CCPortal

DOI	10.1175/JCLI-D-19-0654.1
	North pacific upper-ocean cold temperature biases in CMIP6 simulations and the role of regional vertical mixing
	Yuchao Z.H.U.; Zhang R.-H.; Sun J.
发表日期	2020
ISSN	0894-8755
起始页码	7523
结束页码	7538
卷号	33 期号:17
英文摘要	Substantial model biases are still prominent even in the latest CMIP6 simulations; attributing their causes is defined as one of the three main scientific questions addressed in CMIP6. In this paper, cold temperature biases in the North Pacific subtropics are investigated using simulations from the newly released CMIP6 models, together with other related modeling products. In addition, ocean-only sensitivity experiments are performed to characterize the biases, with a focus on the role of oceanic vertical mixing schemes. Based on the Argo-derived diffusivity, idealized vertical diffusivity fields are designed to mimic the seasonality of vertical mixing in this region, and are employed in ocean-only simulations to test the sensitivity of this cold bias to oceanic vertical mixing. It is demonstrated that the cold temperature biases can be reduced when the mixing strength is enhanced within and beneath the surface boundary layer. Additionally, the temperature simulations are rather sensitive to the parameterization of static instability, and the cold biases can be reduced when the vertical diffusivity for convection is increased. These indicate that the cold temperature biases in the North Pacific can be largely attributed to biases in oceanic vertical mixing within ocean-only simulations, which likely contribute to the even larger biases seen in coupled simulations. This study therefore highlights the need for improved oceanic vertical mixing in order to reduce these persistent cold temperature biases seen across several CMIP models. Ó 2020 American Meteorological Society.
英文关键词	Boundary layer flow; Boundary layers; Diffusion; Oceanography; American meteorological societies; Cold temperatures; Coupled simulation; Static instability; Surface boundary-layer; Temperature simulations; Vertical diffusivity; Vertical mixing; Mixing; climate; CMIP; computer simulation; instability; numerical model; seasonal variation; temperature effect; vertical mixing; Pacific Ocean; Pacific Ocean (North)
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/171167
作者单位	CAS Key Laboratory of Ocean Circulation and Waves, Institute of Oceanology, Chinese Academy of Sciences, and Pilot National Laboratory for Marine Science and Technology (Qingdao), Center for Ocean Mega-Science, Chinese Academy of Sciences, Institute of Oceanographic Instrumentation, Shandong Academy of Sciences, Qingdao, China; Center for Excellence in Quaternary Science and Global Change, Chinese Academy of Sciences, Xian, University of Chinese Academy of Sciences, Beijing, China; Institute of Oceanographic Instrumentation, Shandong Academy of Sciences, Qingdao, China
推荐引用方式 GB/T 7714	Yuchao Z.H.U.,Zhang R.-H.,Sun J.. North pacific upper-ocean cold temperature biases in CMIP6 simulations and the role of regional vertical mixing[J],2020,33(17).
APA	Yuchao Z.H.U.,Zhang R.-H.,&Sun J..(2020).North pacific upper-ocean cold temperature biases in CMIP6 simulations and the role of regional vertical mixing.Journal of Climate,33(17).
MLA	Yuchao Z.H.U.,et al."North pacific upper-ocean cold temperature biases in CMIP6 simulations and the role of regional vertical mixing".Journal of Climate 33.17(2020).