DOI: 10.1002/joc.5468
论文题名: Extratropical cyclones over the southwestern South Atlantic Ocean: HadGEM2-ES and RegCM4 projections
作者: Reboita M.S. ; da Rocha R.P. ; de Souza M.R. ; Llopart M.
刊名: International Journal of Climatology
ISSN: 8998418
出版年: 2018
卷: 38, 期: 6 起始页码: 2866
结束页码: 2879
语种: 英语
英文关键词: extratropical cyclones
; future climate
; HadGEM2-ES
; precipitation
; RegCM4
; southwestern South Atlantic Ocean
Scopus关键词: Earth (planet)
; Precipitation (chemical)
; Storms
; Dynamic downscaling
; Extratropical cyclones
; Future climate
; Global climate model
; RegCM4
; Regional climate modeling
; Relative vorticity
; South Atlantic
; Climate models
; climate modeling
; climate prediction
; downscaling
; ensemble forecasting
; extratropical cyclone
; Hadley cell
; precipitation (climatology)
; regional climate
; vorticity
; Atlantic Ocean
; Atlantic Ocean (South)
英文摘要: The value added from dynamic downscaling in climate projections of extratropical cyclones over the southwestern South Atlantic Ocean (SAO) is evaluated. For this purpose, the Regional Climate Model version 4 (RegCM4) is nested in the Hadley Global Environment Model 2 - Earth System (HadGEM2-ES) global climate model under the RCP8.5 scenario. The analyses focus on three time slices: the present (1979–2005), near future (NF: 2020–2050) and far future (FF: 2070–2098) climates. The cyclone tracking used an algorithm that searches for minima of relative vorticity at 925 hPa. Simulations of the present climate are compared to data from an ensemble of five reanalyses (ERA-40, ERA-Interim, NCEP-NCAR, NCEP-DOE and CFSR). For present climate, there is good agreement among reanalyses and models in associating austral winter and summer with higher and lower cyclone frequency, respectively. In addition, the simulations present the mean features of the cyclones (lifetime, distance travelled and mean velocity) as similar to those of the reanalysis. Moreover, RegCM4 outperforms the HadGEM2-ES by simulating more realistically the spatial pattern of the cyclogenesis density over the SAO, which indicates value added from the RegCM4 downscaling. For the future climates, a decrease is projected for the annual frequency of cyclones, which reaches −6.5% (−3.6%) in RegCM4 (HadGEM2-ES) in the NF and −11.4% (−10.4%) in the FF. Future projections do not indicate changes in the mean intensity of the cyclones. The negative trend of the cyclone frequency affects the precipitation. For FF, a decrease of approximately 15% in the precipitation associated with cyclones is projected. © 2018 Royal Meteorological Society Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/116894
Appears in Collections: 气候减缓与适应
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作者单位: Instituto de Recursos Naturais, Universidade Federal de Itajubá, Minas Gerais, Brazil; Departamento de Ciências Atmosféricas, Universidade de São Paulo, São Paulo, Brazil; Departamento de Física, Universidade Estadual Paulista (UNESP), São Paulo, Brazil; Centro de Meteorologia de Bauru (IPMet), São Paulo, Brazil
Recommended Citation:
Reboita M.S.,da Rocha R.P.,de Souza M.R.,et al. Extratropical cyclones over the southwestern South Atlantic Ocean: HadGEM2-ES and RegCM4 projections[J]. International Journal of Climatology,2018-01-01,38(6)