Optimization of sequential code for simulation of solar radiative transfer in a vertically heterogeneous environment

This article belongs to the series of works aimed at improving computing capacity of radiation codes implementing the Monte Carlo statistical method. A short description is given of the main blocks of basic (FORTRAN version) and optimized (C version) codes designed for calculation of sky radiance in a vertically heterogeneous medium. We present the results of tests which were aimed at evaluating the performance of each of the codes under different conditions in numerical experiments. In the cases examined, the performance indicators of the optimized C code were higher as compared with the basic one. It is shown that differences in execution time of the codes are reduced by increasing the optical density of the atmosphere, and using more productive computers. The developed C code can serve as a basis for creating a high-performance radiation code.