Dipole Types of Autumn Precipitation Variability Over the Subtropical East Asia‐Western Pacific Modulated by Shifting ENSO

Abstract

Recent autumns have exhibited two dipole types of precipitation variability (DIPO1 and DIPO2) over the subtropical East Asia‐western Pacific (SEAWP). Meanwhile, El Niño–Southern Oscillation (ENSO) has undergone significant mode shift, exhibiting as the eastern Pacific or central Pacific ENSO (EPSO or CPSO). Whether there was any physical linkage between the two remains unclear. Here we demonstrate for the first time that interannual variations of DIPO1 and DIPO2 are closely linked to EPSO and CPSO, respectively. Shifting ENSO modulates the patterns of SEAWP precipitation dipole mainly via changing the path of tropospheric moisture transport and the location of anomalous water vapor convergence/divergence due to different low‐level cyclone/anticyclone activities induced by EPSO or CPSO. Further analysis shows that the interdecadal variability of SEAWP precipitation is also linked to the La Niña‐like climate shift in 1998. Hence, our study provides some new insight into the ongoing hot debate on the shifting ENSO and increasing autumn drought in southeastern China.

Roles of August Kuroshio SST Anomaly in Precipitation Variation during September over Central China

“…El Niño-Southern Oscillation (ENSO), the strongest signal of interannual variations in the air-sea coupled system, has been extensively revealed by previous studies to induce autumn precipitation anomalies in China. The eastern-Pacific and central-Pacific types of El Niño change the transport path of tropospheric moisture and the location of anomalous water vapor divergence by affecting the Hadley circulation and the Western North Pacific Subtropical High (WNPSH), which further result in opposite precipitation anomalies in the southern China (Zhang et al, 2013;Gu et al, 2014;Zhang et al, 2014;Hu et al, 2018;Yuan and Wang, 2019). Additionally, the effects of La Niña on the subtropical and even midlatitude atmospheric circulations can lead to anomalous precipitation in the south and north of China, respectively (Feng and Wang, 2018;Yuan and Wang, 2019).…”

A Long‐Lasting Precipitation Deficit in South China During Autumn‐Winter 2020/2021: Combined Effect of ENSO and Arctic Sea Ice

“…However, recent studies indicate that the relationship between the tropical Pacific sea surface temperatures (SSTs) and the East Asian climate is quite complex and unstable. During autumn, the eastern Pacific type of El Niño and the central Pacific type of El Niño may cause opposite precipitation anomalies in southeastern China (Hu et al., 2018). During winter, the relationship between the ENSO and the East Asian water vapor flux as well as precipitation is notably different among December, January, and February (Sun et al., 2019b).…”

Interdecadal changes of summer precipitation dominant mode over East Asia‐Northwest Pacific around late 1990s

“…As mentioned above, the East Asian circulation and global SST all underwent dramatic interdecadal changes in the late 1990s. However, the research on summer precipitation interdecadal change is mainly concentrated on eastern mainland China rather than the EA‐NWP (Huang et al ., 1993; Jiang et al ., 2008; Gong et al ., 2013, 2014; Wang et al ., 2015a; Wang et al ., 2016; Hu et al ., 2018). It is not clear whether this opposite relationship of precipitation in EA‐WNP is stable before and after the late 1990s.…”