Atmospheric QBO phenomenon affects stratospheric winds

Meteorologists are monitoring the Quasi-Biennial Oscillation (QBO), a phenomenon occurring 20 to 30 kilometers above the Earth where tropical stratospheric winds periodically shift between easterly and westerly phases. This cycle, which averages approximately 28 months, can influence weather patterns in regions such as Europe.

The history of understanding this system dates back to the 1883 eruption of Krakatoa in Indonesia, which allowed scientists to track high-altitude air currents. While the QBO involves moving bands of wind rather than a simultaneous rotation at all altitudes, the phases descend gradually over time. This means different layers of the stratosphere can experience different wind directions simultaneously.