长治农业气候资源的变化特征分析

对1961-2000年长治市11个县（市）平均气温和降水资料的变化特征进行统计分析。结果表明：长治气候趋向变暖，特别是20世纪90年代气温升高明显，冬季增温的贡献最大；降水为减少趋势，从1977年开始降水减少明显，1977—1984年为降水匮乏期，1985—2000年呈波动性减少。进一步分析发现：气候变化导致盛夏农业干旱事件发生的频次增多，90年代几乎每年盛夏出现干旱事件；暴雨过程次数从80年代起逐渐减少，90年代减少明显；80年代初开始终霜冻日期提前，初霜冻日期推迟；70年代起无霜期逐渐延长；稳定≥10℃的活动积温随年代增加。这些变化必将影响到农业生产的布局和结构。

Analysis on Change Characteristics of Agricultural Climate Resources in Changzhi City

Based on the meteorological data of eleven counties in Changzhi City from 1961 to 2000, the change characteristics of the mean temperature and precipitation was statistically analyzed. It was concluded that the climate was warming up in Changzhi City, in particular in the 1990s, and warming up in winter was most significantly. The precipitation was decreasing and with a significant trend from the beginning of 1977. Between 1977 and 1984 it experienced a period of spare precipitation and a fluctuated decrease from 1985 to 2000. The climate change led to an increase in drought events, in particular in midsummer in 1990s. The frequency of the rainstorm process decreased from 1980s, and significantly in 1990. From early 1980s, the first frost date advanced, but the late frost date was slightly late by 1.3 days each 10 years. The active accumulated temperature of ≥ 10℃ steadily increased. The frostless season had gradually extended since 1970s. These characters would affect the layout and structure of agricultural production and crop planting.