辽宁省不同历时年最大降水量空间特征

Spatial Characteristics of Different Duration Annual Maximum Rainfall of Liaoning Province

选择辽宁省61处雨量站1981—2013年的10 min—3 d中8个历时的年最大降水量资料,在分析各时段年最大降水量多年均值空间分布规律的基础上,采用EOF分解方法分析了各时段年最大降水量空间结构。结果表明:(1)对于较短历时10 min和60 min,各时段年最大降水量的多年均值在全省除了葫芦岛和丹东两个暴雨中心外,还存在其他较分散的局部高值或低值中心,随着历时延长,葫芦岛绥中县的暴雨中心逐渐明显,其余的局部高值或低值中心消失;(2)随着历时由短到长,EOF分解的方差解释量逐渐向第1主分量集中,年最大3 d降水量的第1主分量解释方差达29.5%,说明随着历时增加,年最大降水量存在占据主导地位的空间分布模态;(3)辽宁省短历时年最大降水量空间一致性差,随机性强;长历时时段年最大降水量在空间分布上趋于同步。

Based on the annual maximum rainfall data of 8 durations（10 min,30 min,60 min,3 h,6 h,12 h,24 h,3 d） of 61 rainfall stations from 1981 to 2013,the spatial distribution of the mean of annual maximum rainfall of different durations are analyzed,and the spatial structures of annual maximum rainfall are investigated by EOF analysis.The results indicate that for short durations（10 min and 60 min）,besides two storm centers at Huludao and Dandong,there are other local high and low value centers scattering at the remainder area.As the durations prolong,the storm center at Huludao become more obvious,while the other local high or low data centers disappear.EOF analysis show that as the duration prolong,the explained variance concentrates to the first principal component,i.e.,29.5% variance is explained by the first principal for the maximum 3 d rainfall,indicating that there is a major spatial distribution mode for long duration maximum rainfall.The annual maximum rainfall for short durations is irregular over Liaoning Province and become consistent spatially as the durations prolong.