黑龙江省春季透雨初日气候特征及环流分析

为了提高黑龙江省春季透雨气候预测为农服务防灾减灾的能力。采用黑龙江省62站逐日降水资料，NCEP/NCAR再分析资料，通过气候趋势分析和EOF、相关及合成等统计方法。结果显示：黑龙江省春季透雨呈显著提前趋势，平均由东部开始出现，最终到西部；最早出现是4月1日，有12年在4—5月20个站以上没出现；可分为一致性、东西反向型及中部与东西相反型；与春季尤其是4月降水呈现显著反相关；偏早年时，前期秋冬季北半球500 hPa距平场由高纬到中纬是“-+”的排列，反之是“+-”；与4月500 hPa环流相关场，在贝湖到黑龙江省西部为正相关，副热带地区为负相关。通过分析表明掌握气候背景及变化特征，利用北半球500 hPa环流场前期秋冬季和4月的变化，对透雨预测有很好指示意义。

First Spring Soaking Rain in Heilongjiang: Climatic Characteristics and Circulation Analysis

The paper aims to improve the forecast of the first spring soaking rain in Heilongjiang, and to prevent and mitigate disasters for agricultural production. Based on the daily precipitation data of 62 stations in Heilongjiang and NCEP/NCAR reanalysis data, we conducted the study by adopting the climate trend, EOF, correlation and synthesis methods. The results showed that: the spring soaking rain in Heilongjiang showed a significant advance trend, it started in the east and eventually reached the west on average; the earliest in history was April 1, and it did not appear at more than 20 stations during April-May for 12 years; it could be divided into 3 types: consistency, east- west inverse, central- east&west inverse; there was a significantly inverse correlation with precipitation in spring, especially in April; in early years, in the early autumn andwinter, the 500 hPa circulation anomaly field in the northern hemisphere was in the order of“-+”from high latitude to mid-latitude, and on the other hand was“+-”; in April, the 500 hPa circulation correlation field was positively correlated from Lake Baikal to the western part of Heilongjiang, while it was negatively correlated in the subtropical region. The analysis shows that grasping the climatic background and variation characteristics and using the variations of 500 hPa circulation field in the northern hemisphere in early autumn, winter and April could have a good guiding significance for the forcast of the first spring soaking rain.