关键词: 新疆, 不同等级, 冷空气过程, 频次, 变化特征

Abstract: Based on the daily minimum temperature data of 89 national meteorological stations from January 1961 to February 2017, within the single station cold air rate according to the Cold Wave Level (GB/T 21987-2008) and Cold Air Grade (GB/T 20484-2006) in the National Standard of the People's Republic of China and the Cold Air Process Monitoring Index (QT/T 21987-2008) in the People's Republic of China Meteorological Industry Standard, we applied of linear trend, EOF decomposition and other analytical methods, and calculated the occurrence frequency, temperature drop and continuous days of the cold wave process of Xinjiang in the past 56 years, and the temporal and spatial distribution characteristics of the single-station cold wave in Xinjiang were analyzed. The results show, 1) Xinjiang single station different levels of cold air annual average frequency and the cumulative number of days are the medium cold air up, the second most cold wave, strong cold air at least, spatial distribution characteristics were presented in northern Xinjiang more, southern Xinjiang less. 2) The annual mean frequency and annual cumulative number of medium strength and strong cold air showed no significant decrease trend, interannual fluctuations are more obvious. 3) Medium strength and strong cold air in the early fall and late spring occurred more, cold wave occurred in the winter more. 4) The cumulative temperature drop of the cold air above the medium strength are showing the distribution characteristics of the northern Xinjiang more, southern Xinjiang less, and the distribution of the regional average is significantly reduced. 5) The first mode of annual cold wave frequency and accumulative temperature drop were 33% and 39%, far more than other mode, and their spatial distribution of the first mode were expressed as a positive value for the whole of Xinjiang, and the characteristic value of northern Xinjiang is larger than southern Xinjiang, indicating that their trends are consistent with the characteristics of the trend, while the northern Xinjiang is more prone to abnormal, southern Xinjiang is not easy to abnormal. Prior to the 1980s, their coherence interannual variability was mainly for positive phase, indicating that there is much more likely to be consistent, since 2000, the time coefficient is mainly in the negative phase, indicating that there is less coincidence.

Key words: Xinjiang, different grades, cold air process, frequnce, change characteristics