近38年高青县无霜期的气候变化特征分析

Analysis of Climate Characteristics in Frost-free Period for the nearly 38 Years in Gaoqing County

利用高青县1972-2009年地面气象观测资料,采用气候统计方法,运用Microsoft Excel计算工具,对高青县霜期气候特征及变化进行了分析。结果表明,近38a来高青县初霜日最早出现在10月5日,最晚出现在11月12日,平均初霜日出现在10月22日;终霜日最早出现在2月11日,最晚出现在4月28日,平均终霜日出现在3月30日;无霜期平均205d,无霜期绝对变率比初、终霜日绝对变率大,终霜日绝对变率比初霜日绝对变率大。12月霜期出现频率最多,1月次之。20世纪70年代初霜期推迟,终霜期提前,无霜期较长;80-90年代初霜期提前,终霜期推迟,无霜期出现近38a来最短时期;2000年后初霜期推迟,终霜期提前,无霜期出现近38a来最长时期。

Based on ground meteorological observation data from 1972 to 2009 of gaoqing county,it analyzed the frosty climate characteristics and changes of Gaoqing county by using statistical methods to climate,calculating by Microsoft Excel.The results showed that for nearly 38 years the First Frost Date(FFD) in Gaoqing county appeared in October 5,the latest of FFD in November 12,the average in October 22,the Last Frost Date firstly in February 11,the latest of LFD in April 28 and the average in March 30,frost-free period was almost 205 days,the absolute change rate of frost-free period was higher than that of the FFD and LFD,and the absolute change rate of LFD was higher than that of FFD.frosty frequency of December was the highest,and January followed.In 1970s,first frost period was delayed,last frost period was brought forward,frost-free period became longer.From 1980s to 1990s,first frost period was brought forward,last frost period was postponed and frost-free period appeared the shortest period for nearly 38 years.After 2000,first frost period was postponed,last frosty earlier,frost-free period became the longest period.It showed that in 1970s Gaoqing county staged in a relatively warm climate period,while from 1980s to 1990s,in a relatively cold period and from the beginning of 2000 climate tended warmer and warmer evidently.