黑龙江省多水期降水特征

Characteristics of Precipitation in Heilongjiang Province During Rainy Periods

利用1961—2020年降水量数据,运用累积距平和滑动平均方法,确定黑龙江省降水年代际变化发生时间,比较多水期与少水期降水差异,对比分析不同多水期降水的多时间尺度特征,得出结论:1961年以来,黑龙江省年降水量经历多—少—多—少—多的演变,1966年以前降水量偏多,1967—1982年偏少,1983—1998年偏多,1999—2011年偏少,2012—2020年偏多。黑龙江省多水期降水量平均偏多13.4%,主要发生在46°~48°N;少水期降水量平均偏少7.7%,主要发生在西部和中南部。第一多水期降水量为554.6 mm,相对基准气候期偏多5.4%,主要发生在西南部,夏秋季降水偏多,冬春季降水量偏少;第二多水期降水量为638.6 mm,偏多21.4%,主要发生在东北部,各季降水都偏多。相较第一多水期,第二多水期夏季逐小时降水频率8月偏多,7和6月偏少,主要表现在午后。

Based on the precipitation data from 1961 to 2020,combined with the methods of cumulative anomaly and the moving average,occurrence time of the inter-decadal variation in Heilongjiang province was determined.The precipitation difference between the rainy period and the drier period were compared,and the multipletime scales of precipitation characteristics in the two periods were compared and analyzed.The results showed that:Since 1961,the annual precipitation in Heilongjiang province has been undergone the evolution of“more-less-more-less-more”.There was a lot of precipitation before 1966,less from 1967 to 1982,more from 1983 to 1998,less from 1999 to2011,and more from 2012 to 2020.The average precipitation in Heilongjiang province during the rainy period was 13.4%more than the reference climate period,mainly between 46°N and 48°N;the average precipitation in the low rainfall period was 7.7%less,mainly in the western and central-southern regions.The precipitation in the first rainy period was 554.6 mm,which was 5.4%more than the reference climate period,mainly in the southwest,with more precipitation in summer and autumn,and less precipitation in winter and spring;the second rainy period had a precipitation of638.6 mm,21.4%higher,mainly in the northeast,the precipitation in each season was high.Compared with the first rainy period,the hourly precipitation frequency in summer in the second rainy period increased in August and decreased in July and June,mainly in the afternoon.