滑动邻域克立格在降水中应用.pdfVIP

滑动邻域克立格在降水中的应用 熊敏诠 Xiong Minquan 国家气象中心, 北京，100081 National Meteorological Center Xiong Minquan. Application of moving neighborhood kriging in precipitation Abstract The fundamental algorithm of gridded weather elements forecast for National Meteorological Center is moving neighborhood kriging. The shortcoming of this algorithm is analyzed. After considered the characterize of precipitation field, direction neighborhood method is proposed to sort data points to get more accurate interpolation result in this paper. The range and nugget effect in precipitation simulation are argued as important part of the variogram. Based on daily precipitation of 2200 site in china and eight regions divided in china, interpolation verification is made in the eight regions grid dataset with 0.28125° resolution respectively. The result show that direction neighborhood method has better accuracy and calculate efficiency than ordinary fixed radius krigging ; Precipitation relation area is reflected under the maximum radius from 4 °to 5 ° approximately; The nugget effect of precipitation is weak. Key words moving neighborhood kriging , variogram , direction neighborhood 摘 要 滑动邻域克立格方法是国家气象中心气象要素预报格点化业务的基础算法。本文详 细分析了滑动邻域克立格存在的不足，结合降水场的特点，考虑了克立格邻近点选择原则， 提出了方位邻近法进行观测点选择策略，并讨论了变异函数在降水拟合中的变程和块金（或 屏蔽）效应的问题。利用2009 年全国2200 个观测站降水资料，把全国划分成八个区，对每 个区域0.28125 网格的插值场进行检验分析，结果表明：方位邻近法在精确度和计算效率上 均优于普通固定半径滑动邻域克立格方法；最大影响半径为4°至5°时能较好地反映降水 量影响范围；降水量的块金效应弱。 关键词：滑动邻域克立格，变异函数，方位邻近 中图法分类号 P456.9 1 引言 降水量观测和预报在都是在相对固定的人工站点进行探测和制作发布，全国观测站呈离 散分布、疏密不均；与高度离散的实况观测和预报相比，格点化的观测和预报场有着更为广 泛的应用前景，在数值模式评估、精细化预报、数值产品解释应用、气候分析等多领域的研 究和应用业务中对降水量格点场资料的需求在不断增长，国外格点化方法已有较完整的理论 和方法体系，国内相关研究也要一定的成果。插值算法是站点资料格点化的基础，有多种插 值算法可供选择，对于不同的变量和各异的分布特征，寻找一种相比其他方法具有绝对的优 势的算法是比较困难的，研究表明：插值过程中不仅仅是要考虑到算法本身的合理性，更重 要的是深入分析如何同插