DOI: 10.1007/s00382-011-1241-8
Scopus记录号: 2-s2.0-84867008540
论文题名: WRF ensemble downscaling seasonal forecasts of China winter precipitation during 1982-2008
作者: Yuan X. ; Liang X.-Z. ; Wood E.F.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2012
卷: 39, 期: 2017-07-08 起始页码: 2041
结束页码: 2058
语种: 英语
英文关键词: Ensemble downscaling
; Precipitation prediction
; Seasonal climate forecast
; WRF
英文摘要: The non-hydrostatic Weather Research and Forecasting model (WRF) was nested into NCEP's operational seasonal forecast model Climate Forecast System (CFS) to downscale seasonal prediction of winter precipitation over continental China. Using the same initial conditions, 16 ensemble downscaling forecasts configured with two alternative schemes of microphysics, cumulus, land surface and radiation in WRF were conducted at 30 km for 27-cold seasons (December-February) during 1982-2008. On average, WRF downscaling forecasts reduced wet bias of seasonal mean precipitation from CFS prediction by 25-71%, decreased errors by up to 33%, and increased equitable threat score by 0. 1 for low threshold. With appropriate physical configurations, WRF could improve interannual variations over the region where CFS has correct anomaly signal. The spatial distribution of daily precipitation characteristics such as rainy frequency and extremes highlighted the sensitivity of downscaling forecasts to physical configurations, and the dominant uncertainties were introduced by land surface and radiation schemes. The differences in convective and resolved rainfall between alternative land surface and radiation schemes were consistent with differences of surface downwelling shortwave and longwave radiation through cloud-radiation feedback. Such feedback was strengthened in the land surface sensitivity experiments due to different parameterizations of surface albedo. As compared with CFS ensemble predictions with different initial conditions, the WRF ensemble downscaling forecasts with various physical schemes had larger spread, and some schemes could complement each other in different regions that provided a promising opportunity to enhance the prediction through optimization. The optimized WRF reduced error from the optimized CFS by 30% and increased pattern correlation by 0. 12. Moreover, WRF physical configuration ensemble increased percentage of skillful probabilistic forecasts from CFS initial condition ensemble. © 2011 Springer-Verlag.
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/55158
Appears in Collections: 过去全球变化的重建
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作者单位: Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ 08544, United States; Department of Atmospheric and Oceanic Science, and Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, United States
Recommended Citation:
Yuan X.,Liang X.-Z.,Wood E.F.. WRF ensemble downscaling seasonal forecasts of China winter precipitation during 1982-2008[J]. Climate Dynamics,2012-01-01,39(2017-07-08)