Modeling M(3000)F2 based on empirical orthogonal functionanalysis method

Abstract

An empirical orthogonal function (EOF) analysis, combined with a regressionanalysis, is conducted to construct an empirical model for the ionospheric propagationfactor M(3000)F2. First, a single station model is constructed using monthly medianhourly values of M(3000)F2 data observed at Wuhan Ionospheric Observatory(geographic 114.4°E, 30.6°N; 45.2°dip) during the years of 1957-1991 for demonstratingthe modeling technique based on EOF expansion and regression analysis of the EOFcoefficients. The constructed climatological model incorporates the diurnal, seasonal aswell as solar-cycle variations of M(3000)F2. A comparison between the observationalresults and the modeled ones showed good agreement. Then, an attempt is made to modelglobal M(3000)F2 data using data from stations distributed around the world. Ourpreliminary result showed that the modeling technique based on EOF expansion, which iscombined with regression analysis of the EOF coefficients as described in this paper, isvery promising when used in global modeling and is worthwhile to investigate further. Copyright 2008 by the American Geophysical Union.