"Models are often the only way of interpreting measurements to in-
vestigate long-range transport, and this is the reason for the emphasis
on them in many research programs". B. E. A. Fisher: "A review of the
processes and models of long-range transport of air pollutants",
Atmospheric Environment, 17(1983), p. 1865. Mathematical models are
(potentially, at least) powerful means in the efforts to study
transboundary transport of air pollutants, source-receptor relationships
and efficient ways of reducing the air pollution to acceptable levels. A
mathematical model is a complicated matter, the development of which is
based on the use of (i) various mechanisms describing mathematically the
physical and chemical properties of the studied phenomena, (ii)
different mathematical tools (first and foremost, partial differenti- al
equations), (iii) various numerical methods, (iv) computers (especially,
high-speed computers), (v) statistical approaches, (vi) fast and
efficient visualization and animation techniques, (vii) fast methods for
manipulation with huge sets of data (input data, intermediate data and
output data).