Dynamical Madden–Julian Oscillation forecasts using an ensemble subseasonal-to-seasonal forecast system of the IAP-CAS model

Liu, Yangke; Bao, Qing; He, Bian; Wu, Xiaofei; Yang, Jing; Liu, Yimin; Wu, Guoxiong; Zhu, Tao; Zhou, Siyuan; Tang, Yao; Qu, Ankang; Fan, Yalan; Liu, Anling; Chen, Dandan; Luo, Zhaoming; Hu, Xing; Wu, Tongwen

doi:https://doi.org/10.5194/gmd-17-6249-2024

Articles | Volume 17, issue 16

https://doi.org/10.5194/gmd-17-6249-2024

© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/gmd-17-6249-2024

© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 17, issue 16

Model experiment description paper

|

23 Aug 2024

Model experiment description paper |

| 23 Aug 2024

Dynamical Madden–Julian Oscillation forecasts using an ensemble subseasonal-to-seasonal forecast system of the IAP-CAS model

Yangke Liu, Qing Bao, Bian He, Xiaofei Wu, Jing Yang, Yimin Liu, Guoxiong Wu, Tao Zhu, Siyuan Zhou, Yao Tang, Ankang Qu, Yalan Fan, Anling Liu, Dandan Chen, Zhaoming Luo, Xing Hu, and Tongwen Wu

Data sets

Input data of the IAP-CAS S2S system Qing Bao et al. https://doi.org/10.5281/zenodo.10820243

NCEP FNL Operational Model Global Tropospheric Analyses, continuing from July 1999 National Centers for Environmental Prediction/National Weather Service/NOAA/U.S. Department of Commerce https://doi.org/10.5065/D6M043C6

NOAA 0.25-degree Daily Optimum Interpolation Sea Surface Temperature (OISST), Version 2.1 Boyin Huang et al. https://doi.org/10.25921/RE9P-PT57

NCEP GFS 0.25 Degree Global Forecast Grids Historical Archive National Centers for Environmental Prediction/National Weather Service/NOAA/U.S. Department of Commerce https://doi.org/10.5065/D65D8PWK

The Subseasonal to Seasonal (S2S) Prediction Project Database (https://apps.ecmwf.int/datasets) F. Vitart et al. https://doi.org/10.1175/BAMS-D-16-0017.1

Model code and software

An ensemble subseasonal-to-seasonal forecast system of IAP-CAS model Qing Bao et al. https://doi.org/10.5281/zenodo.10791355

Dynamic MJO forecasts using an ensemble subseasonal-to-seasonal forecast system of IAP-CAS model Y. Liu https://doi.org/10.5281/zenodo.10817813

Short summary

We give an overview of the Institute of Atmospheric Physics–Chinese Academy of Sciences subseasonal-to-seasonal ensemble forecasting system and Madden–Julian Oscillation forecast evaluation of the system. Compared to other S2S models, the IAP-CAS model has its benefits but also biases, i.e., underdispersive ensemble, overestimated amplitude, and faster propagation speed when forecasting MJO. We provide a reason for these biases and prospects for further improvement of this system in the future.