DOI: 10.1175/JCLI-D-17-0180.1
Scopus记录号: 2-s2.0-85040590074
论文题名: ENSO forecasts near the spring predictability barrier and possible reasons for the recently reduced predictability
作者: Lai A.W.-C. ; Herzog M. ; Graf H.-F.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2018
卷: 31, 期: 2 起始页码: 815
结束页码: 838
语种: 英语
英文关键词: El Nino
; ENSO
; Oscillations
; Statistical forecasting
Scopus关键词: Climatology
; Coastal zones
; Forecasting
; Nickel
; Oceanography
; Surface waters
; Wind effects
; Climate prediction centers
; EL Nino
; ENSO
; Oscillations
; Potential temperature
; Sea surface temperature anomalies
; Statistical forecasting
; Subsurface temperature
; Climate models
; climate oscillation
; climate prediction
; El Nino
; El Nino-Southern Oscillation
; forecasting method
; hindcasting
; Kelvin wave
; sea surface temperature
; spring (season)
; statistical analysis
; temperature anomaly
; temperature gradient
; Pacific Ocean
; Pacific Ocean (Central)
; Pacific Ocean (East)
; Pacific Ocean (West)
英文摘要: A cross-validated statistical model has been developed to produce hindcasts for the 1980-2016 November-December-January (NDJ; assumed El Niño peak) mean Niño-3.4 sea surface temperature anomalies (SSTA). A linear combination of two parameters is sufficient to successfully predict the peak SSTA: 1) the 5°N-5°S, 130°E-180°, 5-250-m oceanic potential temperature anomalies in February and 2) the 5°N-5°S, 140°E-160°W cumulative zonal wind anomalies (ZWA), integrated from November (one year before) up to the prediction month. This model is simple but is comparable to, or even outperforms, many NOAA Climate Prediction Center's statistical models during the boreal spring predictability barrier. In contrast to most statistical models, the predictand Niño-3.4 SSTA is not used as a predictor. The explained variance between observed and predicted NDJ Niño-3.4 SSTA at a lead time of 8 months is 57% using 5 yr for cross validation and 63% in full hindcast mode.Predictive skill is lower after 2000 when the mean climate state is more La Niña-like because of stronger equatorial easterly ZWA. Strengthened Pacific subtropical highs are observed, with weaker westerly ZWA that emerge at a later time during El Niño. The western Pacific is more recharged, with stronger upwelling over the eastern Pacific. The resulting strong zonal subsurface temperature gradient provides a high potential for Kelvin waves being triggered without strong westerly ZWA. However, the persistent easterly ZWA lead to more central Pacific-like El Niños. These are more difficult to predict because the contribution of the thermocline feedback is reduced. Overall, the authors find that the importance of the recharge state for ENSO prediction has increased after 2000, contradicting some previous studies. © 2018 American Meteorological Society.
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/111720
Appears in Collections: 气候减缓与适应
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作者单位: Centre for Atmospheric Science, University of Cambridge, Cambridge, United Kingdom; Hong Kong Observatory, Hong Kong
Recommended Citation:
Lai A.W.-C.,Herzog M.,Graf H.-F.. ENSO forecasts near the spring predictability barrier and possible reasons for the recently reduced predictability[J]. Journal of Climate,2018-01-01,31(2)