近50年晋城地区霜冻变化特征分析

Analysis of the Feature of the Frost Events Change in Jincheng Region in Recent 50 Years

摘要:  利用气候分析法分析了晋城地区1961~2010年霜冻的气候变化特征；利用异常霜冻指标，分析了霜冻的异常发生情况。结果表明：晋城地区初霜日平均值为10月15日，时间序列绝对变率为8.27 d，线性倾向率为1.125 d/10a，有推后的趋势，初霜日变化年际差异大，有很大的预报难度；终霜日平均值为4月7日，时间序列绝对变率为7.25 d，线性倾向率为0.257 d/10a，有弱的推后趋势，终霜日变化年际差异较大，有预报难度；而无霜期平均值为189 d，绝对变率为8.09 d，线性倾向率为1.32 d/10a，无霜期有较明显的增加趋势。异常霜冻年份很少，偏早初霜冻对于部分年份的秋粮作物可能会产生较大影响；高寒地区春播幼苗主要会受到特晚终霜冻的影响；冬小麦遭受终霜冻危害的频率平均为6年一遇，拔节后5天内发生频率较大。

Abstract:   Climatological statistics method was used to analyze climate characteristics of frost in Jincheng region during 1961-2010, and abnormal frost index was used to analyze abnormal occurrence of frost. The results indicated that the average value of the first frost day was October 15, the absolute variability of time series was 8.27 days, and the linear trend was 1.125 d/10a. Thus the first frost day showed the delaying trend, and the first frost day has a big annual difference making forecasting difficult. For the latest frost days, the average value was April 7, the absolute variability of time series was 7.25 days, and the linear trend was 0.257 d/10a. Thus the latest frost days showed weak delaying trend just like the first frost day, and the forecasting to the latest frost days was difficult. For frostless period, the average value was 189 d, the absolute variability of time series was 8.09 days, and the linear trend was 1.32 d/10a. Thus the frostless period showed an obvious growth trend. In addition, abnormal frost years were very few, and the early first frost day for part of the year of autumn grain crops may produce a great influence. Spring sowing seedlings in high altitude were mainly affected by later frost. On average, frequency of winter wheat under frost damage was once every six years, and the frequency was larger within 5 days after jointing stage.