Graphical Abstract

Shibata, K. and H. Naoe, 2021: Decadal amplitude modulations of the stratospheric quasi-biennial oscillation. J. Meteor. Soc. Japan, 100,
Early Online ReleaseGraphical Abstract NEW GA


Plain Language Summary: Analyses of Singapore radiosonde and reanalysis data from 1950s show that the quasi-biennial oscillation (QBO) in the equatorial stratosphere is decadally modulated in the amplitude as well as in the period. These two decadal variations are positively correlated with each other after 1980s, while they show approximately negative correlation before 1980s. The decadal amplitude variations of the QBO are not correlated with the solar cycle, but closely and positively correlated with the decadal components of Niño 3.4 sea surface temperature anomalies (SSTa), Pacific decadal oscillation (PDO) index, and North Pacific gyre oscillation (NPGO) index, suggesting that the tropical SSTa in the central Pacific substantially influences the QBO in the decadal time-scales.