Seasonal Predictability of the Quasi-Biennial Oscillation Based on the Current Dynamical Models

Abstract

The quasi-biennial oscillation (QBO) is the dominant mode of interannual variability in the tropical stratosphere and influences climate worldwide. This study investigates the seasonal predictability of QBO in eight dynamical forecasting models from international operational centers and organizations. Results show that current dynamical models have high skills in predicting the QBO evolution benefiting from their capability of characterizing the typical downward propagation of QBO. Further analyses show that most models can reasonably reproduce the QBO teleconnection patterns, but with weaker amplitude than observation, which may be due to the underestimation of the Holton-Tan effect in models. Prediction skills of the QBO teleconnections to winter surface climate patterns are not yet satisfactory in some models though they have quite high QBO skills. These results provide a comprehensive evaluation of current status of the QBO dynamical seasonal prediction and thus a deeper understanding of the QBO seasonal predictability, which would shed light on predicting QBO and its teleconnection.