Decadal changes of the intraseasonal oscillation during 1979–2016  

作　　者：WU Nan LI Ying LI Juan FENG Li-Cheng LIU Fei 

机构地区：[1]Earth System Modeling and Climate Dynamics Research Center,Nanjing University of Information Science and Technology,Nanjing,210044,China [2]Shanghai ZhongChuan NERC-SDT Co.,Ltd,Shanghai,201114,China [3]National Marine Environmental Forecasting Center,Ministry of Natural Resources,Beijing,100081,China [4]Key Laboratory of Marine Hazards Forecasting,National Marine Environmental Forecasting Center,Ministry of Natural Resources,Beijing,100081,China [5]School of Atmospheric Sciences Sun Yat-sen University,Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies,and Southern Marine Science and Engineering Guangdong Laboratory,Zhuhai,519082,China

出　　处：《Advances in Climate Change Research》2021年第6期772-782,共11页气候变化研究进展（英文版）

基　　金：This work was supported jointly by Guangdong Major Project of Basic and Applied Basic Research(2020B0301030004);the National Key Research and Development Program(2018YFC1505802);the Natural Science Foundation of China(41975107,41576029).

摘　　要：The Intraseasonal Oscillation (ISO) is the cornerstone for 2–8-week subseasonal prediction. Understanding the decadal variation of the ISO is important for improving subseasonal prediction;however, there is still a gap in our knowledge of ISO dynamics. Here, we presented a method, an Empirical Orthogonal Function (EOF) analysis of 11-year-sliding ISO evolution, to objectively detect decadal variation of the ISO originated from the equatorial Indian Ocean (EIO) during 1979–2016. The results show that the properties of ISO have a notable decadal change since 1998 for both boreal summer and boreal winter seasons, mainly in its evolution rather than in its intensity at origin. During the pre-1998 epoch, the boreal summer intraseasonal oscillation (BSISO), was confined to the Indian Ocean;since 1998, however, it propagated northeastward across the Maritime Continent (MC) and the intraseasonal variability over the western North Pacific was significant enhanced. On the other hand, the boreal-winter ISO, usually known as Madden-Julian Oscillation (MJO) shows minor changes in MC ‘barrier effect’ between the two epochs, and continuously propagates eastward across the MC. The MJO only shows suppressed activity over the central equatorial Pacific in the post-1998 epoch. These decadal changes are related to the eastern Pacific cooling during the ‘global warming hiatus’ period rather than to the four-decade global warming. Results here provide a set of potential precursors for foreseeing ISO propagation under different mean states.

关 键 词：Decadal variation Intraseasonal oscillation Madden-Julian oscillation Boreal summer intraseasonal oscillation Global warming hiatus 

分 类 号：P73[天文地球—海洋科学]