摘要
选取北疆50个观测站1971—2015年的逐日平均气温和最低气温资料,运用小波分析、M-K突变检验等统计方法分析了北疆地区不同等级冷空气活动过程的时空变化特征。分析表明:近45 a北疆地区冷空气活动持续日数在1～15 d,平均持续日数为1.79 d。其中弱冷空气过程持续日数以1～2 d为主;中等强度冷空气、较强冷空气和寒潮过程以1～3 d为主;而强冷空气过程以2～4 d为主。近45 a北疆单站冷空气发生频次为95.3次/a,且具有盆地多、山地少的特点;其中中等强度冷空气为11.8次/a,自东向西逐渐减少;弱冷空气、较强冷空气发生频次为70.9次/a、1.8次/a,呈自西南向东北逐渐减少的趋势;强冷空气和寒潮发生频次为4.2次/a、7.3次/a,呈现由西南向东北增加趋势。近45 a北疆地区冷空气活动频次总体呈减少趋势,年代际表现为先减少后增加的特点,20世纪70年代最多,90年代最少,减少速率为0.33/10 a;弱冷空气和较强冷空气呈增加趋势,增加速率为0.17/10 a和0.03/10 a;中等强度冷空气、强冷空气和寒潮活动频次呈下降趋势,其中寒潮的下降速率达-0.37/10 a;不同等级冷空气活动频次均存在一个15～20 a的显著周期,突变点出现在1980、2003年左右。
The daily average temperature and minimum temperature data of 50 stations in northern Xinjiang from 1971 to 2015 were selected in this paper.The spatial and temporal variation characteristics of cold air activity in the northern Xinjiang region were analyzed by using wavelet analysis and M-K mutation test.The resalts indicate that:in the last 45 years,cold air activity in the northern Xinjiang region lasted from 1 to 15 days,with an average duration of 1.79 days.The duration of the weak cold air process was 1~2 days.Moderate strength of cold air,strong cold air and cold wave process with 1~3 days mainly.The strong cold air process was mainly 2~4 days.In the last 45 years,the frequency of cold air in the north Xinjiang single station was 95.3 times per year.It had the characteristics of more frequency in the basin and less in the mountainous area.The moderate cold air was 11.8 times per year.It gradually decreases from east to west.Weak cold air and strong cold air frequency was 70.9 times per year and 1.8 times per year respectively,withethe trend of decreasing from southwest to northeast.The occurrence frequency of strong cold air and cold wave was 4.2 times per year and 7.3 times per year.The trend was increased from southwest to northeast.In the last 45 years,the frequency of cold air activity in northern Xinjiang had decreased.The annual intergenerational performance was characterized by a reduction in the first generation,most in the 1970s and least in the 1990s.The reduction rate was 0.33/10 a.Weak cold air and strong cold air showed an increasing trend.The increase rate was 0.17/10 a and 0.03/10 a.The frequency of moderate cold air,strong cold air and cold wave was decreasing.The decrease rate of the cold wave was-0.37/10 a.There was a significant period of 15~20 years in the frequency of cold air activity in different grades.The mutational site were around 1980 and 2003.
作者
刘红霞
王飞
杨温萍
黄玲
LIU Hongxia;WANG Fei;YANG Wenping;HUANG Ling(Center for Central Asia Atmospheric Science Research,Urumqi 830002,China;Institute of Desert Meteorology,China Meteorological Administration,Urumqi 830002,China;Tacheng Meteorological Bureau,Tacheng 834700,China;Qinghe Meteorological Bureau,Altay 836200,China;Hutubi Meteorological Bureau,Changji 831200,China)
出处
《沙漠与绿洲气象》
2019年第1期70-78,共9页
Desert and Oasis Meteorology
基金
中央级公益性科研院所基本科研业务费专项(IDM2016003)
(IDM201502)联合资助
关键词
冷空气
时空特征
统计分析
北疆地区
cold air
spatiotemporal characteristics
statistic analysis
northern Xinjiang region
