大样本降水空间插值研究——以2009年中国年降水为例  

Study on Spatial Interpolation of Precipitation with Large Scale Samples:A Case Study on 2009' s Precipitation of China

作　　者：曾红伟[1,2] 李丽娟[1] 张永萱[3] 柳玉梅[1,2] 

机构地区：[1]中国科学院地理科学与资源研究所,北京100101 [2]中国科学院研究生院,北京100049 [3]北京师范大学地理学与遥感科学学院,北京100875

出　　处：《地理科学进展》2011年第7期811-818,共8页Progress in Geography

基　　金：国家科技支撑计划课题(2008BAH31B01);科技部科技基础性工作专项(2008FY110300-01)

摘　　要：以2009年全国2203个气象台站累积降水数据为例,采取逐步抽稀方法,定量分析大样本的数据样本量、样本空间分布、以及不同空间插值方法对插值结果的影响。研究表明:①在随机抽样中,总体而言,平均绝对误差(MAE)、均方根误差(RMSE)随着插值样本量的减小而增加、相关系数递减,特别当抽样比<20%时,MAE、RMSE显著增加,R2显著减少;②以Thiessen多边形剖分的方式检验随机抽样、等间隔抽样、分区单站点控制面积约束抽样分布的均匀性,经交叉验证后知,样本空间分布对降水空间插值的结果影响比较复杂,并非越均匀越好;③对随机组中抽样比4%的数据和等间隔组,采用Kriging方法插值,插值结果优于IDW方法。以等间隔分布的(50%,50%)(、20%,80%)数据为例,采用IDW、Kriging方法,得到2009年全国降水空间分布图,降水空间分布规律与中国2009年实际降水量分布吻合。This paper studies spatial interpolation of precipitation at a national scale,the precipitation data comes from 2203 meteorological stations of China in 2009.The research content includes three parts as follows.At first,this paper divided the stations into different groups by stochastic methods,including 90%,80%,70%,60%,50%,40%,30%,20%,10%,5% and 4% sampling rate groups,and analyzed the impact of sampling data on interpolation result by inverse distances weighting methods.Secondly,the stations with 80%,50% and 20% of sampling rates were treated by the same sampling interval method,which extracted sampling data with gaps equal 1 or 4 according to ID serial number.By comparing interpolation result with the result by stochastic meth-od in the same sampling rate,this paper analyzed the relationship between sampling methods of data and the re-sult of interpolation.Finally,the paper analyzed the differences of interpolation result by IDW,Kriging and Co-Kriging in the same sampling rate groups.We can draw some conclusions as follows：（1） Using IDW meth-ods,MAE and RMSE decreased gradually as the amount of sampling data increased,while the correlation coeffi-cient decreased at the same time.The increase from 50% to 90% was slow with slight fluctuations,and that from 20% to 50% became obvious.Especially,when the sampling fraction 〈20%,MAE and RMSE were increased significantly,and the correlation coefficient was significantly reduced.（2） We found that the relationship be-tween uniform of stations distribution and precipitation interpolation results was complex after cross-validation,and sometimes it did not have better interpolation result under more uniform distribution of stations.（3） With not only the random sampling data,but also the same interval sampling data,MAE and RMSE using IDW meth-ods were large than Kriging interpolation method,while R2 was smaller.It is suggested that Kriging interpola-tion was better than IDW method in this paper.Taking 50% and 20% sampling rate groups as an example,using IDW

关 键 词：大样本量 样本空间分布 空间插值方法 Thiessen多边形 中国 

分 类 号：P426.613[天文地球—大气科学及气象学]