气候变化领域集成服务门户(CCPortal): An intercomparison of subtropical cut-off lows in the Southern Hemisphere using recent reanalyses: ERA-Interim; NCEP-CFRS; MERRA-2; JRA-55; and JRA-25

CCPortal

DOI	10.1007/s00382-019-05089-1
	An intercomparison of subtropical cut-off lows in the Southern Hemisphere using recent reanalyses: ERA-Interim; NCEP-CFRS; MERRA-2; JRA-55; and JRA-25
	Pinheiro H.R.; Hodges K.I.; Gan M.A.
发表日期	2020
ISSN	0930-7575
起始页码	777
结束页码	792
卷号	54 期号:2020-01-02
英文摘要	Four recent reanalysis products ERA-Interim, NCEP-CFSR, MERRA-2 and JRA-55 are evaluated and compared to an older reanalysis JRA-25, to quantify their confidence in representing Cut-off lows (COLs) in the Southern Hemisphere. The climatology of COLs based on the minima of 300-hPa vorticity (ξ300) and 300-hPa geopotential (Z300) provides different perspectives of COLs and contributes to the understanding of the discrepancies observed in the literature regarding their numbers and seasonality. The COLs compare better among the newest reanalyses than compared to the older reanalysis JRA-25. The difference in number between the latest reanalyses are generally small for both ξ300 and, with more COLs identified in ξ300 than in Z300 for all reanalyses. The spatial differences observed between the newest reanalyses are mainly due to differences in the track lengths, which is larger in ERA-Interim and JRA-55 than in NCEP-CFSR and MERRA-2, resulting in disparities in the track density. This is likely due to the difference in the assimilation data system used in each reanalysis product. The largest differences in intensities occur in the ξ300, because this field is very sensitive to the reanalysis resolution. The mean separation distance of the COLs that match between the latest reanalyses are generally small, while the older JRA-25 has a broader distribution and larger number of matches with relatively large distances, indicating larger uncertainties in location of COLs. The results show significant improvements for the most recent reanalyses compared to the older JRA-25 reanalysis, indicating a progress in representing the COL properties. © 2019, The Author(s).
英文关键词	Climatology; Comparison; Cut-off lows; Objective identification; Reanalysis
语种	英语
scopus关键词	climatology; comparative study; data assimilation; geopotential; low pressure system; seasonality; Southern Hemisphere; vorticity
来源期刊	Climate Dynamics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/145719
作者单位	Center for Weather Forecast and Climate Studies, National Institute for Space Research, Sao Jose dos Campos, SP, Brazil; Department of Meteorology, The University of Reading, Reading, United Kingdom
推荐引用方式 GB/T 7714	Pinheiro H.R.,Hodges K.I.,Gan M.A.. An intercomparison of subtropical cut-off lows in the Southern Hemisphere using recent reanalyses: ERA-Interim; NCEP-CFRS; MERRA-2; JRA-55; and JRA-25[J],2020,54(2020-01-02).
APA	Pinheiro H.R.,Hodges K.I.,&Gan M.A..(2020).An intercomparison of subtropical cut-off lows in the Southern Hemisphere using recent reanalyses: ERA-Interim; NCEP-CFRS; MERRA-2; JRA-55; and JRA-25.Climate Dynamics,54(2020-01-02).
MLA	Pinheiro H.R.,et al."An intercomparison of subtropical cut-off lows in the Southern Hemisphere using recent reanalyses: ERA-Interim; NCEP-CFRS; MERRA-2; JRA-55; and JRA-25".Climate Dynamics 54.2020-01-02(2020).