Reexamining the Decadal Variation in the ENSO-East Asian Winter Monsoon Relationship

Although numerous studies have paid attention to the unstable relationship between the El Nino/Southern Oscillation (ENSO) and East Asian winter monsoon (EAWM), significant discrepancies have existed, especially regarding the modulation of the Pacific decadal oscillation (PDO) and Atlantic multidecadal oscillation (AMO). Here, we reexamine this issue by applying a new method that considers the changing relationship between ENSO and the spatial variations of the EAWM rather than a given EAWM index. We suggest a complicated spatial-temporal variation in the ENSO-EAWM relationship (EER), which consists of two major modes regulated by the PDO and AMO in distinct ways. In other words, the PDO and AMO modulate two different aspects of the decadal EER, which helps to clarify the disagreements among previous studies that are generally based on specific and regional EWAM indices.