DOI: 10.1002/jgrd.50465
论文题名: Decadal prediction of the dominant West African monsoon rainfall modes
作者: García-Serrano J. ; Doblas-Reyes F.J. ; Haarsma R.J. ; Polo I.
刊名: Journal of Geophysical Research Atmospheres
ISSN: 21698996
出版年: 2013
卷: 118, 期: 11 起始页码: 5260
结束页码: 5279
语种: 英语
英文关键词: Atlantic multidecadal variability
; Atlantic Niño
; Decadal prediction
; West African monsoon
Scopus关键词: Atmospheric movements
; Atmospheric pressure
; Atmospheric temperature
; Global warming
; Mean square error
; Rain
; Decadal predictions
; Deep tropical convection
; Interannual variability
; Multidecadal variability
; Positive correlations
; Root mean square errors
; Sea surface temperature anomalies
; West African Monsoon
; Forecasting
; annual variation
; Atlantic Multidecadal Oscillation
; atmospheric convection
; atmospheric modeling
; climate prediction
; decadal variation
; El Nino
; ensemble forecasting
; error analysis
; marine atmosphere
; monsoon
; rainfall
; seasonal variation
; Atlantic Ocean
; West Africa
英文摘要: The present study offers for the first time the validation of decadal prediction systems upon the West African monsoon (WAM) variability. The ENSEMBLES multimodel and perturbed parameter decadal reforecasts are used to assess multiyear prediction skill for the dominant WAM precipitation regimes. Thus, the focus of the assessment is on time scales longer than seasonal to interannual. To retain lower-frequency predictability (interannual to decadal), a 4 year average is applied, which indeed has been shown to remove most of the interannual variability that is unpredictable beyond 1 year in dynamical forecasting (e.g., El Niño-Southern Oscillation). First, the decadal hindcasts are analyzed to assess forecast skill of Guinean and Sahelian area-averaged rainfall indices. Findings suggest that there is no significant skill in predicting these rainfall indices, probably due to the distinctive representations of deep tropical convection in each forecast system. This is further addressed by computing and comparing the leading modes of WAM variability in the ENSEMBLES decadal reforecasts against observations. Results show that while in the observations, global warming has an important role, in the forecast systems, the Atlantic Ocean is the main player. The Atlantic Niño represents the leading forcing for the simulated Guinean precipitation. Sea surface temperature (SST) anomalies associated with the simulated Sahelian precipitation project onto the Atlantic multidecadal variability (AMV), in which the subtropical branch shows consistency across the forecast systems. No significant skill has been found, however, to predict these WAM precipitation modes, although the Sahelian pattern presents systematic positive correlation scores and lower root mean square errors along the whole forecast range. This is reflected in a tendency for reproducing the Sahel dry period around the 1980s. Likewise, the good performance across the models in simulating the relationship between the leading rainfall modes and the surrounding SST forcings points out encouraging prospects for decadal forecasting. Previous studies show multiyear prediction skill of the AMV in the ENSEMBLES decadal reforecasts. Here the skill of the Atlantic-3 SST index is discussed. © 2013. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/63694
Appears in Collections: 影响、适应和脆弱性 气候减缓与适应
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作者单位: Institut Català de Ciències Del Clima (IC3), Barcelona, Spain; Instituciõ Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain; Koninklijk Nederlands Meteorologisch Instituut (KNMI), De Bilt, Netherlands; Department of Meteorology, University of Reading, Reading, United Kingdom
Recommended Citation:
García-Serrano J.,Doblas-Reyes F.J.,Haarsma R.J.,et al. Decadal prediction of the dominant West African monsoon rainfall modes[J]. Journal of Geophysical Research Atmospheres,2013-01-01,118(11)