Possibilities of Improving the TD88 Atmospheric Total Density Model

In this paper we have examined possibilities for preserving and improving the total density model of the Earth's neutral thermosphere TD88 (Sehnal and Pospisilova 1988) via modelling differences between TD88 and NRLMSISE-00 (Picone et al. 2002), which is used as a control model. It is shown that these residuals can be approximated with polyharmonic function. Starting from this we have developed the mathematical model of the residuals to identify their origin and possibilities to improve the TD88 model itself.