辽宁省农业干旱频发区首场透雨气候特征

利用1961~2013年辽宁省农业干旱易发区春播期首场透雨出现的日期及首场透雨量资料,采用线性回归、M-K检验法,分析了近53年该区春播期首场透雨出现的日期及首场透雨量的时空分布及气候学变化特征。结果表明,辽宁省农业干旱频发区透雨发生日期较晚,透雨量较少。透雨发生日期和透雨量空间分布均呈东南至北部方向逐渐递减的特征,沿海各站春播期首场透雨量普遍高于内陆地区。区域平均透雨发生日期和透雨量均有年际变化特征,但趋势不明显。各站春播期首场透雨发生日期多呈随时间逐渐提前、透雨量多呈增多趋势,但变化趋势均未通过显著性检验。研究时段内无透雨过程出现的个例占总数的8.4%,内陆及西部各站较沿海及其他地区更易出现春播期无透雨现象。

Climatic Characteristics of the First Soaking Rain in Agricultural Drought-prone Areas in Liaoning Province

Based on the date and quantity of the first soaking rain in agricultural drought-prone areas in Liaoning Province during 1961-2013,the characteristics of spatial and temporal distribution and climate change in recent 53 years were analyzed by linear regression,M-K test method.The results indicated that the date of the first soaking rain in agricultural drought-prone areas in Liaoning Province appears late and the soaking rainfall quantity is small.The date of the first soaking rain and the soaking rainfall have the same spatial characteristics of decrease from southeast to north.The interdecadal variations of regional average of the date of the first soaking rain and the soaking rainfall are insignificant.The date of the first soaking rain of most weather stations appears earlier and the soaking rainfall is increasing.During the research period,the cases of no soaking rain emergence accounted for 8.4%,no soaking rain in spring sowing period was more easily occurred in inland and western stations than that in coastal and other regions.