高寒地区1961—2017年无霜期及其积温变化特征

Frost-free Periods in High-cold Region During 1961-2017:Variation Characteristics and the Accumulated Temperature

为有效防御和减轻霜冻灾害对高寒贵南地区农牧业生产的影响,为合理开展农牧业气候区划提供可靠依据。利用青海省高寒地区贵南县气象局观测的1961-2017年逐日最低气温、平均气温资料,采用线性倾向估计、M-K突变分析等方法,对高寒地区贵南县霜冻初日、终日、无霜期及同时期积温变化特征进行分析。结果表明:1961-2017年高寒地区贵南县≤0℃霜冻的终日呈极显著的提前趋势,初日呈显著的后延趋势,终日提前的幅度大于初日后延的幅度;无霜期呈现极显著延长趋势,无霜期积温呈现极显著的升高趋势。霜冻终日在1972年发生了提前突变,霜冻初日和无霜期在1970年发生了延迟突变,无霜期积温在1977年发生了升高突变。

The paper aims to effectively prevent and mitigate the impact of frost disaster on agricultural production in high-cold region of Guinan, Qinghai, and provide a reliable basis for reasonable development of agricultural climate regionalization. Based on data of daily average air temperature and daily minimum temperature of Guinan meteorological station from 1961 to 2017, by using linear tendency estimation and M-K mutation analysis, several elements were analyzed, including the first frost date, the last frost date, the frostfree period, and the accumulated temperature of the frost-free period. The results showed that the first frost date displayed a significantly delayed trend, and the last frost date had a significantly early trend, and the change range of the last frost date was higher than that of the first frost date. The frost-free period presented a significantly extending trend, and the accumulated temperature of the frost-free period significantly increased.The last frost date was abruptly ahead of schedule in 1972, the first frost date and the frost-free period had an abrupt delay in 1970, and the accumulated temperature of the frost-free period increased abruptly in 1977.