离散点气象要素平流外推模型

Advection Extrapolation Model of Meteorological Elements at Discrete Points

大气平流方程一般用于格点场数值预报的处理,鲜有应用到离散点要素外推。离散点平流外推模型不仅使时间方向站点资料补缺更具物理意义,而且为站点要素的预报奠定基础。模型首先根据站点离散特征,对平流方程进行改造,得到离散点风速、梯度本征向量,并通过频数统计拟合出平流项似然概率的高斯表达式,以此计算出新平流方程数值解。通过对单点和多点的实况试验,得出了模型的具体应用特点,并给出了一个实际的数据补缺场景,作用显著。该模型具有小巧、高效,易用等特点,有良好的普适性,作为一个通用的数学模型,为离散点的要素预报提供了一种新的思路。

Atmospheric advection equations are generally used for numerical forecast on the grid field.It is rarely applied to the extrapolation of discrete elements.The extrapolation of model discrete elements not only makes the data filling in time more meaningful,but also lays the foundation for forecasting elements of a site.The model,based on discrete site characteristics,reforms the advection equation to get the wind speed of sites and gradient eigenvectors.The Gauss expression of the likelihood probability of the advection terms is fitted by the frequency statistics,and the numerical solution of the new-style advection equation is calculated.Through the single-point and multi-point actual tests,the specific application characteristics of the model are obtained,and a real data filling case is given.The results indicate that it worked well.The model is compact,efficient and easy to use,has good universality.As a general mathematical model,it provides a new idea for the element prediction at discrete points.