This study revisits precipitation change in East Asia caused by the Madden-Julian oscillation (MJO) and its interannual variation due to the quasi-biennial oscillation (QBO). Specifically, boreal-winter precipitation, derived from weather stations across China, Korea, and Japan, is examined for MJO phases 2–3 and 6–8. Consistent with previous findings, precipitation in southern China and southern Japan increases by up to 36% during MJO phases 2–3, when the MJO convection is located in the Indian Ocean. In contrast, during MJO phases 6–8, precipitation decreases by 13%. More importantly, these MJO-related precipitation anomalies become larger and more organized when the QBO is in its easterly phase. The difference in precipitation anomalies between the QBO easterly and westerly phases is approximately 40% for MJO phases 2–3 and 70% for MJO phases 6–8 from southern China to Japan. This result reaffirms that the QBO can affect surface weather in the northern extratropics through MJO teleconnection.
Bibliographical noteFunding Information:
This work was funded by the Korea Meteorological Administration Research and Development Program under grant KMI2018-01011. OMI used as the MJO index is available online (https://www.esrl.noaa.gov/psd/mjo/mjoindex/). NOAA ONI v5 index used as the ENSO index is available online (https://origin.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ONI_v5.php). The observed precipitation data used in this study are available online (CMA: https://data.cma.cn/en/?r=data/detail&dataCode=SURF_CLI_CHN_MUL_DAY_CES_V3.0; JMA: http://www.data.jma.go.jp/gmd/risk/obsdl/index.php; KMA: https://data.kma.go.kr/data/grnd/selectAsosRltmList.do?pgmNo=36). ERA-Interim reanalysis data are available online (https://apps.ecmwf.int/datasets/data/interim-full-daily/). Other precipitation data for supporting materials are also available online, TRMM 3B42 data (https://pmm.nasa.gov/data-access/downloads/trmm), CMAP pentad data (https://www.esrl.noaa.gov/psd/data/gridded/data.cmap.html), and CPC gauge-based precipitation data (https://ftp.cpc.ncep.noaa.gov/precip/CPC_UNI_PRCP/) are used.
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- East Asia precipitation
- Madden Julian oscillation
- MJO teleconnection
- quasi-biennial oscillation