Pseudo-Spectral Technique in the Computation of Seasonal Average Concentrations and Its Comparison with the Trajectory Technique

摘要

Since there is now a greater awareness of the chronic effects of exposure to low levels of atmospheric pollutants, the long-range transport of atmospheric material is receiving increasing attention in recent years. Quite a few codes have been designed to study the long-range movement of material in the atmosphere. The ORNL code RETADD (Begovich, Murphy and Nappo, 1978) is an example of such a code. Codes such as RETADD operate by following wind trajectories which advect material from a source location and which superimpose a diffusion rate upon the advection process. By storing the results of many trajectory passes, average patterns of ground level concentration are deduced; and by repeating the process, the average pattern resulting from a combination of a number of sources can be deduced. Many current problems require the analysis of the fate of atmospheric effluents associated with a given technology. (ERA citation 07:008524)