Abstract: Using the daily mean/minimum air temperatures data at 8 weather stations in the Nanning area during 1961-2005, we analyzed the change characteristics of cold wave activity in the Nanning area in recent 45 years and the impact of anomalous circulations on the frequency of the cold wave events affecting Nanning. The results show that the cold wave activity period is different in various areas of the Nanning area, that is, the cold wave activity begins early but ends late in the east, while it begins late but ends early in the northwest. The cold waves occur mainly in December, January and February. Over the past 45 years, cold waves had two abnormal changes in the early 1970s and late 1990s. The general trend of cold wave activity is decreasing at a rate of 0.12 time/10 a. This phenomenon is mainly related to the obvious rise in daily minimum temperature. The typical circulation characteristics for strong/weak cold wave activity years are illustrated with respective composite 500 hPa height anomaly fields.

Key words: Nanning area, cold wave, global warming