The episode of Quasi-Biennial Oscillation in 2016 did not have its roots in its distant past; the role of the strong El Ni\~no event

TL;DR

This paper investigates the unusual 2016 QBO event, analyzing its recent nature and exploring its connection to the strong El Niño, challenging the idea that it was rooted in the distant past.

Contribution

It provides a detailed analysis of the 2016 QBO anomaly and examines its potential link to the 2015-2016 El Niño event, offering new insights into their relationship.

Findings

2016 QBO event was unprecedented in recent history

The abnormal QBO behavior may be linked to the strong El Niño

The event was not rooted in the distant past, but recent atmospheric conditions

Abstract

We explore the anomalous behavior of the equatorial quasi-biennial oscillation (QBO) in zonal wind which it exhibited, since February 2016. In more detail, QBO interrupted its regular pattern and the eastward stratospheric winds unexpectedly reversed to a westward direction. We focus on the temporal evolution of the equatorial zonal wind in the altitude region 70 - 10 hPa, investigating particularly whether this unprecedented event could be considered as a result of scaling effect in the equatorial zonal wind. Furthermore, the link between the QBO abnormal behaviour in 2016 with the strong El Ni\~no event is investigated.