Details

Autor(en) / Beteiligte

• Yoo, Changhyun
• Son, Seok‐Woo

Titel

Modulation of the boreal wintertime Madden‐Julian oscillation by the stratospheric quasi‐biennial oscillation

Ist Teil von

• Geophysical research letters, 2016-02, Vol.43 (3), p.1392-1398

Ort / Verlag

Washington: John Wiley & Sons, Inc

Erscheinungsjahr

2016

Quelle

Wiley Online Library

Beschreibungen/Notizen

• Madden‐Julian oscillation (MJO), the dominant mode of intraseasonal variability in the tropical troposphere, has a significant impact on global weather and climate. Here we present that the year‐to‐year variation of the MJO activity shows significant changes with the quasi‐biennial oscillation (QBO) in the tropical stratosphere. Specifically, the boreal winter MJO amplitude, evaluated by various metrics, is typically stronger than normal during the QBO easterly phase at 50 hPa and weaker than normal during the QBO westerly phase at 50 hPa. This relationship, which is possibly mediated by the QBO‐related static stability and/or vertical wind shear changes in the tropical upper troposphere and lower stratosphere, is robust whether or not the activeness of the MJO or QBO is taken into account. This result suggests a new potential route from the stratosphere that regulates the organized tropical convection, helping to improve the prediction skill of the boreal winter MJO. Key Points MJO strengthens (weakens) during EQBO (WQBO) The QBO‐MJO connection is significant during boreal wintertime only The QBO‐MJO connection can be robustly found in various metrics