江西省秋季连阴雨气候变化特征及其对秋收的影响

利用江西省81站1961—2013年9—11月的逐日降水、日照时数等资料,分别以1961—2013年、1961—1990年、1971—2000年、1981—2010年为统计时段,从高风险区域、发生次数、高风险时段等三个方面,对江西省秋季连阴雨变化特征及其对秋收的影响进行了分析。结果表明:江西省秋季连阴雨高风险区域以宜春、吉安两市西部以及萍乡市为高值区;高风险时段为10月下旬;随着气候变化,江西省秋季连阴雨高风险区域范围明显缩小,但高风险时段有所延长,总体上呈少发但重发的趋势;由于10月1日前后及中旬连阴雨年均逐日站次有所减少,对粮食、棉花等秋收作物收获、晾晒有利,其余时段若出现秋季连阴雨,往往发生范围较大、持续时间较长,秋收工作需注意防范。

The Climatic Change Features of Autumn Continuous Precipitation and Their Influence on Autumn Harvesting in Jiangxi Province

By using 1971-2013 daily precipitation data and sunshine duration data of 81 stations in Jiangxi Province during September-November,in respect of high-risk region,frequency and high-risk period,variation characteristics and spatial-temporal distribution of continuous rainfall in autumn of Jiangxi are analyzed. The results show that the center of high-risk area includes Pingxiang,Ji’an and west parts of Yichun. The high-risk period is in the late October. Due to the climate change, the range of the high-risk area is narrowing obviously,while the high-risk period is expanding. The weather condition is favorable to the harvesting and drying of the grain and the cotton due to the decreases of stations with annual average continuous rainfall in the first of October and the middle October. However,in the rest of period, the harvesting and drying of the grain and the cotton should be aware of the adverse effects of the continuous rainfall.