Modeling the atmospheric fate and transport of mercury over North America: power plant emission scenarios

A multiscale modeling system that consists of a global cycling model and a continental-scale model, TEAM, is applied to simulate the fate and transport of mercury over North America. The performance of the modeling system is shown to be satisfactory. TEAM is used to simulate three coal-fired power plant emission control scenarios that correspond to 47%, 30% and 16% reductions in mercury emissions from the 1999 base case. Changes in total mercury deposition are less than 10% over most of the United States. The latter two scenarios that include subcategorization of power plants by coal rank and stack temperature show little effect on mercury deposition compared to the first scenario.