顾及风向和风速的气温空间插值方法

当前气温插值方法多将高程、经纬度等作为影响因素,无法解决风向、风速对气温空间分布的影响问题。该文提出一种顾及风向和风速的气温空间插值方法:1)根据气象观测站点的风向、风速数据进行插值,生成连续的风场表面;2)基于该风场数据利用高斯扩散模型构建成本表面;3)利用Dijkstra最短路径算法计算观测点与待求点的累计移动成本最短路径(SPOCMC);4)将SPOCMC作为协变量进行薄盘光滑样条插值以实现气温插值。为验证该方法的有效性和可靠性,选取山东省109个气象观测点样本数据,以SPOCMC、DEM和SPOCMC-DEM分别作为协变量对气温数据进行薄盘光滑样条插值,结果显示:SPOCMC-DEM法的MAE和RMSE均值(分别为0.517、0.779)略低于SPOCMC法(0.583、1.016),显著低于DEM法(0.809、1.231),表明添加SPOCMC作为协变量可有效提高气温空间插值的准确性。在江苏省与贵州省的插值实验结果证明了该方法的普适性。

A Method of Spatial Interpolation of Air Temperature Considering Wind Direction and Speed

At present,air temperature interpolation methods mostly use variables such as elevation,latitude and longitude as influencing factors,and cannot solve the problem of the influence of wind direction and wind speed on the spatial distribution of air temperature.This paper proposes a spatial interpolation method for air temperature that takes into account wind direction and speed:1) interpolating wind direction and speed data from meteorological observation stations to generate a wind field surface;2) using this wind field to construct a cost surface based on Gaussian diffusion model;3) using Dijkstra shortest path algorithm to calculate the shortest path(SPOCMC) of cumulative moving cost(SPOCMC) between the observation point and the point to be solved;4) using SPOCMC as a covariate to perform the thin-plate smoothing spline interpolation to achieve air temperature interpolation.In order to verify the superiority of this method,109 meteorological observation points in Shandong Province are selected as samples,and SPOCMC,DEM and SPOCMC-DEM are used as covariates to perform the thin-plate smoothing spline interpolation on air temperature data.The result is that:the MAE and RMSE of SPOCMC-DEM method are 0.517 and 0.779 respectively,which are slightly lower than the 0.583 and 1.016 of the SPOCMC method,and are significantly lower than the 0.809 and 1.231 of the DEM method,indicating that this method can effectively improve the accuracy of the air temperature spatial interpolation.The applicability of the proposed method in different regions are proved by the favorable interpolation results in Jiangsu Province and Guizhou Province.