Relationship between the South China Sea summer monsoon withdrawal and September–October rainfall over southern China
- 36 Downloads
This study reveals a significant positive connection between the interannual variation in the South China Sea (SCS) summer monsoon (SCSSM) withdrawal and September–October rainfall over southern China. Specifically, pronounced positive rainfall anomalies can be found around southern China when the withdrawal of the SCSSM is later than normal. The occurrence of the significant SCSSM withdrawal-southern China rainfall relation may be attributed to both the atmospheric internal dynamics and the sea surface temperature (SST) anomalies over the tropical Pacific. In particular, SST warming over the tropical western North Pacific, which resembles the developing phase of a La Niña, could induce a significant anomalous low-level cyclone over the northern SCS via a Rossby wave-type atmospheric response. The southwesterly wind anomalies on the south flank of this anomalous cyclone favor late SCSSM withdrawal and contribute to more rainfall over southern China via the northward transport of water vapor. In addition, the enhanced quasi-biweekly oscillation and synoptic-scale variation (such as tropical cyclones) during late withdrawal years are also conducive to increased rainfall over southern China. Further analyses found notable interdecadal changes and asymmetry in the connection of the SCSSM withdrawal with southern China rainfall. The factors contributing to the nonstationary and asymmetric nature of this monsoon withdrawal-rainfall relationship are also briefly discussed.
KeywordsSouth China Sea Summer monsoon withdrawal Rainfall Southern China Tropical cyclone Interannual variability
We thank two anonymous reviewers for their constructive suggestions and comments, which helped to improve the paper. This study was supported jointly by the National Key Research and Development Program of China (Grant no. 2016YFA0600604), the National Natural Science Foundation of China (Grant 41721004), and the Jiangsu Collaborative Innovation Center for Climate Change. PH thanks Yuqi Wang, Zhiang Xie, and Lin Wang of the Institute of Atmospheric Physics for helpful advice and several discussions. YYL thanks Kaiming Hu of the Institute of Atmospheric Physics for his assistance in the LBM simulation.
Compliance with ethical standards
Conflict of interest
The authors declare no potential conflict of interest.
- Cai Q, Feng W, Li X et al (2013) Technical manual for weather forecast in Hainan Province. China Meteorological Press, BeijingGoogle Scholar
- Ding Y, Si D, Liu Y et al (2018) On the characteristics, driving forces and inter-decadal variability of the East Asian summer monsoon. Chin J Atmos Sci 42(3):533–558Google Scholar
- Goh AZC, Chan JCL (2010) Interannual and interdecadal variations of tropical cyclone activity in the South China Sea. Int J Climatol 30(6):827–843Google Scholar
- Hsu HH (2012) Intraseasonal variability of the atmosphere-ocean-climate systems: East Asian monsoon. In: Lau WKM, Waliser DE (eds) Intraseasonal variability in the atmosphere-ocean climate systems, 2nd edn. Springer, Berlin, pp 73–110Google Scholar
- Lee HT, Schreck CJ, Knapp KR (2014) Generation of the daily OLR climate data record. In: 2014 EUMETSAT Meteorological Satellite Conference, Geneva, Switzerland, 22–26 September 2014Google Scholar
- Liebmann B, Smith CA (1996) Description of a complete (interpolated) outgoing longwave radiation dataset. Bull Am Meteor Soc 77(6):1275–1277Google Scholar
- Lin L, Feng Y, Huang Z et al (2006) Technical manual for weather forecast in Guangdong Province. China Meteorological Press, BeijingGoogle Scholar
- Mao J, Wu G (2008) Influences of Typhoon Chanchu on the 2006 South China Sea summer monsoon onset. Geophys Res Lett 35:L12809Google Scholar
- National Climate Center (2017) East Asian monsoon yearbook 2016. China Meteorological Press, BeijingGoogle Scholar