Synopsis: Combining numerous mercury modeling approaches, this project will advance the capabilities within the region to track mercury emissions, transport, deposition and fate. Models of mercury transport will be applied at several scales, including a global mercury transport model which will inform a regional-scale model of mercury transport. The results of mercury deposition modeling will be linked with efforts to create a multi-media of mercury fate after being deposited to water bodies. In all, this series of models will provide among the most complete portrayals available of the impact of global and regional emissions on the region’s aquatic systems. Mercury emission inventory enhancements will be incorporated into both the global and regional scale models.

Chemicals Studied: The study will focus on mercury, a substance of high concern within the Great Lakes region due to its high toxicity and tendency to accumulate at high levels within fish.

Geographic Areas: The geographic focus of the project is on the Great Lakes region as a whole. Beginning with a model of global mercury emissions and transport, the project will nest within this model a more refined model of emissions and transport within the Great Lakes region.

Project Duration: The project will begin in the Spring of 2006 and complete in the Spring of 2008.

Methods Used: The project consists of several components, including improvements to emissions data sets, modeling activities and data analysis. Emissions inventory improvements will include several enhancements to the emissions data for sources within North America, improved data for global emissions and the inclusion of natural mercury emissions. Modeling approaches will be used on a nested basis, in which the MOZART 3-D model will be used on a global basis, with CMAQ being used at multiple resolutions over the North American continent, with the finest resolution covering the Great Lakes basin. The output from this model will be used as input to models estimating the deposition of mercury to the lakes and the multi-media transport and fate of mercury within the system. The output data from this suite of models will be used to assess the validity of the overall modeling framework, to determine the relative contribution of specific mercury sources to mercury levels within the region’s air and water and to determine the overall budget of mercury cycling within the region.

Potential Results and Implications: Because of its comprehensiveness, this modeling effort will have important implications for policy development efforts that depend upon an accurate understanding of the relative contributions of various mercury sources to mercury concentrations within the Great Lakes and their food chains. While studies have been done of mercury transport on a global and continental level, the nested modeling approach taken here may provide the most thorough data to data on expected mercury transport characteristics. The inclusion of additional emissions data, such as natural sources, will represent a further improvement on past efforts.

Project Contact:
Kevin Crist, Ph.D.
Ohio University
Phone: (740)593-4751
Email: cristk@ohio.edu