Status: this discussion paper is a preprint. It has been under review for the journal Natural Hazards and Earth System Sciences (NHESS). The manuscript was not accepted for further review after discussion.
Role of NAO and ENSO in the anomalous precipitation in the southern part of China – study on the two contrary high impact weather and climate cases
State Key Laboratory of Severe Weather, Chinese Academy of Meteorological Sciences, Beijing 100081, China
Abstract. Their economic and social importance emphasized by the survey of Department of Disaster Relief, Ministry of Civil Affairs of the People’s Republic of China, two different typical patterns of precipitation anomaly in the southern part of China during the 1982/1983 and 2009/2010 cold seasons coincided with the canonical El Niño and positive North Atlantic Oscillation (NAO) and with the El Niño Modoki and negative NAO, respectively. A better understanding of how a particular type of El Niño and a specific phase of NAO worked together to cause the relevant anomalous atmospheric circulation over the East Asia in the two high impact weather and climate cases was an interesting issue and could improve the prediction skill of natural hazards to a certain extent. In conclusion, superimposing on the remote and local Rossby wave responses in the atmosphere induced by the El Niño Modoki-related condensational heat sink over the South China Sea, the downstream extension of the negative NAO was well established by a NAO-induced stationary Rossby wave train along the Asian subtropical jet and played a major role in the persistent dry conditions in the Southwest China for the 2009/2010 boreal winter. On the contrary, for the 1982/1983 boreal winter, the canonical El Niño weakened the downstream extension of the positive NAO, and induced by the canonical El Niño-related condensational heat sink over the western equatorial Pacific Ocean, the remote and local Rossby wave responses in the atmosphere played a leading role in the sustained wet conditions in the South China.
How to cite. Wu, Q.: Role of NAO and ENSO in the anomalous precipitation in the southern part of China – study on the two contrary high impact weather and climate cases, Nat. Hazards Earth Syst. Sci. Discuss. [preprint], https://doi.org/10.5194/nhess-2017-143, 2017.
Received: 14 Apr 2017 – Discussion started: 04 Oct 2017
The two contrary high-impact weather and climate events in the southern part of China occurred during the 1982/1983 and 2009/2010 cold season, additionally, the prominent climate patterns in the boreal winter-the North Atlantic Oscillation (NAO) and the two types of El Nino were under way. Based on previous studies, we made a further investigation on how the NAO and the El Nino worked together to make the two special events, including the asymmetric relationship of NAO with two types of El Nino.
The two contrary high-impact weather and climate events in the southern part of China occurred...