1961-2017年湖南省冷空气活动特征分析

为了准确把握湖南省冷空气活动的时空分布及变化特征，利用1961～2017年湖南省88个地面观测站日最低气温的均一化资料，通过线性回归、M-K突变检验、Morlet小波分析等方法分析湖南省冷空气活动特征，研究结果表明：湖南冷空气活动与地形因素有很大的相关性，弱冷空气在武陵山、雪峰山一带偏多，洞庭湖平原地区偏少，较强冷空气、强冷空气在南岭以及雪峰山、幕阜山、连云山一带偏多，寒潮在南岭、幕阜山、连云山一带偏多。弱冷空气趋势增多，年际变化倾向率为0.277 次?(10 a)-1，较强冷空气、强冷空气、寒潮趋势减少，年际变化倾向率分别为-0.07 次?(10 a)-1、-0.166 次?(10 a)-1、-0.11 次?(10 a)-1。极端冷事件趋势减少，年际变化倾向率为-3.36 d?(10 a)-1。弱冷空气在湘中、湘东等大部分地区趋势增多，较强冷空气在湘西、湘西南地区趋势减少，强冷空气在湘北、湘东北大部分地区趋势减少，寒潮在湘东北、湘西南、湘东南等大部分地区趋势减少。研究结果可为农业、林业、水利、生态以及气象预报预测预警工作提供决策依据。

Characteristics of Cold Air Activity in Hunan Province from 1961 to 2017

In this study, we applied the daily minimum temperature homogeneity data of 88 stations in Hunan Province from 1961 to 2017 to analyze and discuss the characteristics of cold air activities, on the basis of the linear regression, Mann-Kendall (MK) statistical test and Morlet wavelet analysis methods. Our statistical results show that the variation of cold air activities in Hunan Province is greatly related to the local topography. The weak cold air prevails the Mountains of Wuling and Xuefeng, but it is suppressed in Dongting Lake Plain. The strong and stronger cold air are more in the Mountains of Nanling, Xuefeng, Mufu and Lianyun. The cold waves prevail in the Mountains of Nanling, Mufu and Lianyun. Evidences suggest that the weak cold air tends to increase in 0.277 times every decade, while the strong cold air, the stronger cold air, the cold wave tend to decrease in 0.07 times every decade, 0.166 times every decade, 0.11 times every decade. Extreme cold events tend to decrease in 3.36 days every decade. The weak cold air tends to increase in central and eastern Hunan. The strong cold air tends to decrease in western and southwestern Hunan. The stronger cold air tends to decrease in northern and northeastern Hunan. The cold wave tends to decrease in northeastern, southwestern and southeastern Hunan. The extreme cold events tend to decrease in northern Hunan. These results can provide some valuable suggestions for the forecast and projection in the agriculture, forestry, water resources, ecology and meteorology.