Overview

Teaching: 0 min
Exercises: 0 min

Questions

• How to analyze QBO using CMIP6 data?

Objectives

• Learn about QBO

• Learn to analyze CMIP6 data

• Introduction
• Questions
• Data
• References

Introduction

The quasi-biennial oscillation (QBO) (Baldwin et al 2001):

• dominates the variability of the equatorial stratosphere (16-50 km).
• is a downward propagating easterly and westerly wind regimes, with a variable period averaging approximately 28 months.
• is a coherent, oscillating mean flow that is driven by propagating waves with periods unrelated to that of the resulting oscillation.
• affects the stratospheric flow from pole to pole by modulating the effects of extratropical waves (impact on the polar vortices).
• impacts atmospheric dynamics, and chemical constituents (e.g. ozone, water vapor, and methane).

(@FUB)

Research questions

• I. Do CMIP6 models resolve the QBO; what is the QBO period; are there any hickups in the modelled QBO?
• II. QBO impacts?
• III. How is the QBO generated?
• IV. Do increasing GHGs impact the QBO?

Data

• CMIP6 model data, historical period (1850-2014 CE) and future scenarios
• Observations: FUB QBO record (Naujokat et al 1986 and updates; FUB data)

References

• Lecture slides and material
• Naujokat et al., 1986
• QBO review paper: Baldwin et al., 2001
• QBO hick-up: Newman et al., 2016; Osprey et al., 2016; Anstey et al, 2020

Key Points

• QBO