In 1969 the North Atlantic Treaty Organization (NATO) established the
Committee on Chal- lenges of Modern Society (CCMS). The subject of air
pollution was from t, lw start one of the priority problems under study
within the framework of various pilot. studi('s undertaken by this
committee. The organization of a periodic conference dealing with air
pollution modelling and its application has become one of the main
activities within the pilot tudy relatillg to air pollution. The first
five international conferences were organized by the United Statcs as
the pilot country; the second five by the Federal Republic of Germany:
thc third five by ßelgium; the next four by The Netherlands; ami the two
most recent by Delllllark. This volume contains the papers presented at
the 21st NATOjCCMS International Technical Meeting (ITM) on Air
Pollution Modelling and Its Application, held in ßaltimorc. Maryland,
during November 6-10, 1995. This ITM was jointly organized by the Riso
National Laboratory of Denmark (Pilot Country); by the EPA National
Exposurp Research Labora- tory, United States (Host Country); and by thc
American MNeorologiea.! Soci('t.: -. Cnited States (Host Organization).
The ITM was attended by 137 participants representing 29 countri(' from
North and South America, Europe, Asia and Australia. The members of t.hc
NATO/CCMS Scientific Committee for the 21st ITM were R.M. van Aalst (The
Nethcrlallds), D. Allfossi (Haly), C. Borrego (Portugal), N. Chaumerliac
(Francc), H. van Dop (Thc: \Tethcrla.nds). S.-E. Gryning.
