DOI: 10.1007/s00382-017-3665-2
Scopus记录号: 2-s2.0-85017012861
论文题名: Understanding the Central Equatorial African long-term drought using AMIP-type simulations
作者: Hua W. ; Zhou L. ; Chen H. ; Nicholson S.E. ; Jiang Y. ; Raghavendra A.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2018
卷: 50, 期: 2018-03-04 起始页码: 1115
结束页码: 1128
语种: 英语
英文关键词: AMIP
; Central Equatorial Africa
; Drought
; Sea surface temperature
Scopus关键词: anticyclone
; atmospheric forcing
; climate modeling
; drought
; ensemble forecasting
; rainfall
; sea surface temperature
; teleconnection
; Walker circulation
; Central Africa
; Indian Ocean
; Indian Ocean (Tropical)
; Pacific Ocean
; Pacific Ocean (Tropical)
英文摘要: Previous studies show that Indo-Pacific sea surface temperature (SST) variations may help to explain the observed long-term drought during April–May–June (AMJ) since the 1990s over Central equatorial Africa (CEA). However, the underlying physical mechanisms for this drought are still not clear due to observation limitations. Here we use the AMIP-type simulations with 24 ensemble members forced by observed SSTs from the ECHAM4.5 model to explore the likely physical processes that determine the rainfall variations over CEA. We not only examine the ensemble mean (EM), but also compare the “good” and “poor” ensemble members to understand the intra-ensemble variability. In general, EM and the “good” ensemble member can simulate the drought and associated reduced vertical velocity and anomalous anti-cyclonic circulation in the lower troposphere. However, the “poor” ensemble members cannot simulate the drought and associated circulation patterns. These contrasts indicate that the drought is tightly associated with the tropical Walker circulation and atmospheric teleconnection patterns. If the observational circulation patterns cannot be reproduced, the CEA drought will not be captured. Despite the large intra-ensemble spread, the model simulations indicate an essential role of SST forcing in causing the drought. These results suggest that the long-term drought may result from tropical Indo-Pacific SST variations associated with the enhanced and westward extended tropical Walker circulation. © 2017, Springer-Verlag Berlin Heidelberg. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/109465
Appears in Collections: 影响、适应和脆弱性 气候变化事实与影响
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作者单位: Department of Atmospheric and Environmental Sciences, University at Albany, State University of New York, Albany, NY 12222, United States; Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/Joint International Research Laboratory of Climate and Environment Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Nanjing University of Information Science and Technology, Nanjing, 210044, China; Earth, Ocean and Atmospheric Science, Florida State University, Tallahassee, FL 32306, United States
Recommended Citation:
Hua W.,Zhou L.,Chen H.,et al. Understanding the Central Equatorial African long-term drought using AMIP-type simulations[J]. Climate Dynamics,2018-01-01,50(2018-03-04)