Address given at the Global Conference Building a Sustainable World organised by The Brazilian Association for Ecology and Water and Air Pollution Prevention (ABEPPOLAR) and The International Union of Air Pollution Prevention and Environmental Protection (IUAPPA).
The Eta and Aviation (AVN) driving models of HY-SPLIT are evaluated by means of a case study of the sulphur fire plume at Somerset West (34° 04'S, 18° 48'E) which caused sulphur dioxide (SO2) air pollution over Macassar on 16 - 17 December 1995. The HY-SPLIT model is verified by comparing it with the Lagrangian kinematic trajectory (LKT) model. Plume dispersions and depositions of the HY-SPLIT model for the Eta and AVN driving models are compared with Eta model winds. Eta model winds for a grid point close to the fire are verified against radiosonde data and synoptic observations. Results indicate that the finer-resolution regional Eta model has the higher accuracy.
Air Quality measurements near Sasol Secunda facility have been carried out for more that a decade. The network was recently expanded to have three additional stations on a regional scale (80 - 100 km from Secunda), mainly to determine the effect that a sulphur recovery plant upgrade that was started in 2002 will have an ambient concentration of sulphur species.