冀南地区冬季负积温特征及趋势分析

Analysis on the Trend and Negative Accumulated Temperature Characteristics in the Southern Hebei

利用冀南地区1975～2009年16个气象站≤0℃的日平均气温资料,采用趋势分析和小波分析等方法,分析了冀南地区冬季负积温的时空变化情况。结果表明,冀南地区冬季负积温随纬度和海拔高度的升高而增加;负积温的年际变化明显,近35年来负积温总体呈下降趋势;负积温变化主要存在4和8年的周期性振荡。

Based on the average data of daily air temperature which is below 0 ℃ during the periods from 1975 to 2009,the winter negative accumulated temperature was calculated.Using the trend analysis and wavelet analysis method,analyzes the spatio-temporal variation of winter negative accumulated temperature.The results show that winter negative accumulated temperature rises from southeast to northwest with the increasing altitude and elevation.We can see an obvious interannual variability of negative accumulated temperature,during recent 35 years the negative accumulated temperature drops on the whole.The negative accumulated temperature mainly shows an interannual oscillation periods of 4 years and 8 years.