@article{63218393e099446a9519920f69672615,
title = "Influence of the QBO on the MJO During Coupled Model Multiweek Forecasts",
abstract = "Seasonal activity of the Madden-Julian Oscillation (MJO) is observed to be greater during austral summer when the lower stratospheric winds are in the easterly phase of the quasi-biennial oscillation (QBO). Using initialized predictions from two coupled model seasonal prediction systems, we show a systematic impact of the QBO on the amplitude of the MJO during the first few days of the forecast before model biases become too large. In both models as for the observed, the difference in MJO amplitude between easterly phases and westerly phases of the QBO increases with lead time, despite having similar initial amplitudes. Enhanced destabilization of the tropopause is argued to be the key mechanism that promotes stronger MJO convection during easterly phase of QBO. Caveats for the inability of the models to reproduce the observed strength of the MJO-QBO relationship are discussed.",
keywords = "MJO prediction, QBO, QBO-MJO relationship",
author = "S. Abhik and Hendon, {Harry H.}",
note = "Funding Information: SA acknowledges support from the Earth System and Climate Change Hub of the Australian Governments National Environmental Science Programme (NESP). We thank Andrew Marshall for providing RMM indices for POAMA-2. Suggestions from Rob Colman and constructive comments from two anonymous reviewers helped to improve the quality of the manuscript. ERA-Interim reanalysis were downloaded from ECMWF website (https://apps.ecmwf.int/datasets/data/interim_full_daily). Daily interpolated OLR data were obtained from NOAA/ESRL PSD, Boulder, Colorado, USA (https://www.esrl.noaa.gov/psd/data/gridded/data.interp_OLR.html). The ONI index is obtained from http://origin.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ONI_v5.php website. This research was carried out with the assistance of resources and services from the National Computational Infrastructure (NCI) of Australian Government, and the analysis was performed using NCAR Command Language (NCL; https://doi.org/10.5065/D6WD3XH5). Publisher Copyright: {\textcopyright}2019. Commonwealth of Australia.",
year = "2019",
month = aug,
day = "16",
doi = "10.1029/2019GL083152",
language = "English",
volume = "46",
pages = "9213--9221",
journal = "Geophysical Research Letters",
issn = "0094-8276",
publisher = "Wiley-Blackwell",
number = "15",
}