摘要
对冬季平均气温序列采用三分位方法确定单站暖冬阈值,并将单站暖冬分为弱和强两个等级。以此为基础,确定区域暖冬和全国暖冬的界定方法和等级划分标准。区域暖冬采用站点相对比例确定,全国暖冬采用暖冬面积相对比例界定。对我国1952—2007年的暖冬事件变化特征的分析结果表明:南方暖冬频率高于北方,强暖冬多发区出现在我国中西部地区;北方单站暖冬指数上升幅度大于南方,表明北方暖冬事件上升趋势更加明显;以1986年为界,前期(1952—1985年)南、北方各区域均很少出现暖冬,南方各区暖冬频率略高于北方各区,后期(1986—2007年)各区暖冬年大为增加,北方各区增加最明显且超过了南方;56年中,全国性暖冬共发生15次(年),其中强暖冬共有5次(年);全国暖冬指数呈显著上升趋势,在有效面积不变的情况下,暖冬面积每10年增加10%。
The climate of China is now clearly in the global warming up trend,in which the winter warming of the northern China is the most obvious.The influence of the warm winter upon the human society is omnibearing,including the direct or indirect impact on human health,daily life,economy activity,agriculture product and ecological environment.Generally,the warm winter means that the air temperature of winter is higher than the climate normal values(the winter air temperature climatology value from 1971 to 2000).According to the China national standard,the warm winter is classified into two groups by space and intensity grades.In the space group the warm winter is divided into three spatial grads as single station warm winter,regional warm winter,and national warm winter.In the intensity group,there are two grades as weak warm winter(warm winter) and strong warm winter.Average winter air temperature is divided into 3 probability categories to define the threshold of warm winter for single station and its warm winter intensity.Then the division criterions for regional and national winter warm intensity are calculated according to percentile rank of warm winter stations and areas respectively.On the basis of the new division method for warm winter,the characteristics of warm winter since 1952 in China are analyzed too.The analysis reveals that the southern China has a higher frequency of warm winter than northern China,while in mid-west China region strong warm winter occurs more frequently.The rising amplitude of warm winter index is larger in northern China than that in southern part,indicating that the warming trend in northern China is more obvious.During 1952 to 1985,the occurrence of warm winter is rare in the nation-wide of China,when the frequency of warm winter in southern part of China is slightly higher than that happens in the northern part of China.The incidence of warm winter changes from the year of 1986.The number of warm winter year increases since 1986 both in southern and northern China with that of northern part increasing significantly.The results also show that there are 15 national warm winter years over 56 years with 5 strong warm winters.National warm winter index has an obvious rising trend at a warm winter area rate of 10% per 10 years.However,the air temperature has great year-to-year variations,the possible abnormal cold winter should be properly considered even in the obvious global warming trend,and hence impacts of the cold winter shouldn't be neglected.
出处
《应用气象学报》
CSCD
北大核心
2009年第5期539-545,共7页
Journal of Applied Meteorological Science
基金
国家"十一五"科技支撑计划课题(2007BAC03A01)
国家科技支撑计划课题(2007BAC29B06)
国家自然科学基金项目(40575039)共同资助
关键词
暖冬指标
等级划分
地面气温
warm winter
division method
surface air temperature