标题：Application of the Orthogonal Polynomial Fitting Method in Estimating PM2.5 Concentrations in Central and Southern Regions of China
作者：Li, Bingtian; Liu, Yongzhi; Wang, Xinyi; Fu, Qingjun; Lv, Xianqing
作者机构：[Li, Bingtian; Fu, Qingjun] Shandong Univ Sci & Technol, Coll Ocean Sci & Engn, Qingdao 266590, Shandong, Peoples R China.; [Li, Bingtian; Lv, Xianq 更多
通讯作者：Lv, XQ;Lv, XQ
通讯作者地址：[Lv, XQ]Ocean Univ China, CIMST, Phys Oceanog Lab, Qingdao 266200, Shandong, Peoples R China;[Lv, XQ]Qingdao Natl Lab Marine Sci & Technol, Qingdao 26 更多
来源：INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH
关键词：fine particles (PM2; 5); orthogonal polynomial fitting (OPF);; interpolation
摘要：Sufficient and accurate air pollutant data are essential to analyze and control air contamination problems. An orthogonal polynomial fitting (OPF) method using Chebyshev basis functions is introduced to produce spatial distributions of fine particle (PM2.5) concentrations in central and southern regions of China. Idealized twin experiments (IE1 and IE2) are designed to validate the feasibility of the OPF method. IE1 is designed in accordance with the most common distribution of PM2.5 concentrations in China, whereas IE2 represents a common distribution in spring and autumn. In both idealized experiments, prescribed distributions are successfully estimated by the OPF method with smaller errors than kriging or Cressman interpolations. In practical experiments, cross-validation is employed to assess the interpolation results. Distributions of PM2.5 concentrations are well improved when OPF is applied. This suggests that errors decrease when the fitting order increases and arrives at the minimum when both orders reach 6. Results calculated by the OPF method are more accurate than kriging and Cressman interpolations if appropriate fitting orders are selected in practical experiments.