DOI: 10.1175/JCLI-D-11-00100.1
Scopus记录号: 2-s2.0-81155150767
论文题名: Identification and climatology of Southern Hemisphere mobile fronts in a modern reanalysis
作者: Simmonds I. ; Keay K. ; Bye J.A.T.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2012
卷: 25, 期: 6 起始页码: 1945
结束页码: 1962
语种: 英语
Scopus关键词: 850-hPa
; Climate variability
; Cold front
; Eulerian
; Higher latitudes
; Indian ocean
; Latitude belts
; Mean intensity
; Midlatitudes
; Reanalysis
; Semiannual variation
; Southern Hemisphere
; Zonal asymmetry
; Climate control
; Mathematical models
; Climatology
; climate variation
; climatology
; cold front
; Southern Hemisphere
; weather forecasting
; winter
; Indian Ocean
英文摘要: Presented here is an objective approach to identify, characterize, and track Southern Hemisphere mobile fronts in hemispheric analyses of relatively modest resolution, such as reanalyses. Among the principles in its design were that it should be based on broadscale synoptic considerations and be as simple and easily understood as possible. The resulting Eulerian scheme has been applied to the European Centre for Medium-RangeWeather Forecasts (ECMWF) Re-Analysis (ERA)-Interim and a climatology of frontal characteristics, at both the 10-mand 850-hPa levels, derived for the period 1 January 1989-28 February 2009. The knowledge of the character of these features is central to understanding weather and climate over the hemisphere. In both summer and winter the latitude belt 40°-60°S hosts the highest frequency of frontal points, but there are significant zonal asymmetries within this band. The climatology reveals that the longest fronts are in the Indian Ocean where mean lengths exceed 2000 km. The mean frontal intensity over the hemisphere tends to be greater at 850 hPa than at 10 m, and greater in winter than in summer. The frontal intensity also shows its maximum in the Indian Ocean. In the mean, the meridional tilt of these fronts is northwest-southeast over much of the midlatitudes and subtropics, and increases with latitude toward the equator. The tilts are of overwhelmingly opposite sign in the coastal Antarctic and subantarctic regions. Broadly speaking, the number of fronts and their mean length and mean intensity exhibit maxima in winter in the midlatitudes (30°-50°S), but show a sizeable semiannual variation (maxima in fall and spring) during the year at higher latitudes. © 2012 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/52501
Appears in Collections: 气候变化事实与影响
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作者单位: School of Earth Sciences, University of Melbourne, Melbourne, VIC, Australia; Centre for Australian Weather and Climate Research, Bureau of Meteorology, Melbourne, VIC, Australia
Recommended Citation:
Simmonds I.,Keay K.,Bye J.A.T.. Identification and climatology of Southern Hemisphere mobile fronts in a modern reanalysis[J]. Journal of Climate,2012-01-01,25(6)