连州市低温霜冻的气候变化特征

Characteristics of Climatological Variation of Chilling Temperature and Frost in Lianzhou City

根据连州气象站1952—2011年观测资料，采用M—K、回归分析、小波分析等方法研究了连州市低温霜冻的气候变化特征。结果表明：连州市低温和霜冻日数逐年减少；初低温日和初霜冻日呈延后趋势，终霜日则逐年提前。低温和霜冻日数的突变年份分别为1972和1986年；低温日数存在9～10、14～15和22～23年左右的周期变化，霜冻日数存在10～11和27～28年左右的周期变化。

Using observation data of a meteorological station in Lianzhou from 1952 to 2011, we studied the characteristics of climatological variations of chilling temperature and frost with the methods of Mann- Kendall, regression analysis and wavelet analysis. The results are shown as follows. For the Lianzhou city, the numbers of days with chilling temperature and frost are decreasing, with the dates of annually first chilling temperature and frost appearing later than usual but that of annually last frost earlier than usual. The numbers of days with chilling temperature and frost changed abruptly in 1972 and 1986, respectively. The number of days with chilling temperature varies at periods of 9-10, 14-15 and 22-23 years and that of frost fluctuates at periods of 10-11 and 27-28 years.