The lack of a QBO-MJO connection in climate models with a nudged stratosphere
Martin, Z. K., Simpson, I. R., Lin, P., Orbe, C., Tang, Q., et al. (2023). The lack of a QBO-MJO connection in climate models with a nudged stratosphere. Journal of Geophysical Research: Atmospheres, doi:https://doi.org/10.1029/2023JD038722
| Title | The lack of a QBO-MJO connection in climate models with a nudged stratosphere |
|---|---|
| Genre | Article |
| Author(s) | Z. K. Martin, Isla R. Simpson, P. Lin, C. Orbe, Q. Tang, Julie Caron, Chih-Chieh Chen, H. Kim, L. R. Leung, Jadwiga H. Richter, S. Xie |
| Abstract | The observed stratospheric quasi-biennial oscillation (QBO) and the tropospheric Madden-Julian oscillation (MJO) are strongly connected in boreal winter, with stronger MJO activity when lower-stratospheric winds are easterly. However, the current generation of climate models with internally generated representations of the QBO and MJO do not simulate the observed QBO-MJO connection, for reasons that remain unclear. This study builds on prior work exploring the QBO-MJO link in climate models whose stratospheric winds are relaxed toward reanalysis, reducing stratospheric biases in the model and imposing a realistic QBO. A series of ensemble experiments are performed using four state-of-the-art climate models capable of representing the MJO over the period 1980-2015, each with similar nudging in the stratosphere. In these four models, nudging leads to a good representation of QBO wind and temperature signals, however no model simulates the observed QBO-MJO relationship. Biases in MJO vertical structure and cloud-radiative feedbacks are investigated, but no conclusive model bias or mechanism is identified that explains the lack of a QBO-MJO connection. |
| Publication Title | Journal of Geophysical Research: Atmospheres |
| Publication Date | Sep 16, 2023 |
| Publisher's Version of Record | https://doi.org/10.1029/2023JD038722 |
| OpenSky Citable URL | https://n2t.org/ark:/85065/d7df6w8z |
| OpenSky Listing | View on OpenSky |
| CGD Affiliations | CAS, CCR, AMP |