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Hg Deposition
Research Programs
The dynamic process of deposition, chemical conversion and re-emission of the different forms of Hg creates a “bi-directional dynamic” that is central to the multimedia behavior of Hg.
Multimedia Flux for Hg
This work focuses on the multimedia behavior of mercury. The dynamic process of deposition, chemical conversion and re-emission of the different forms of Hg creates a “bi-directional dynamic” that is central to the multimedia behavior of Hg, with the key source of Hg to surface ecosystems being atmospheric deposition (wet and dry). This key process (i.e., secondary transformation and bi-directional flux) is missing in most atmospheric models, including the current version of CMAQ-Hg. This task addresses targeted multimedia model development for 1) coupled surface exchange of Hg between the atmosphere and the Earth’s surface (primarily water) and 2) the estimation of regional to long-range Hg transport and deposition sensitivity to secondary transformation and surface exchange. This task supports Goal 4 (Healthy Communities and Ecosystems) and its Long-Term Goals ECO-6, Forecasting - Assess vulnerability and manage for sustainability, and HG-3, Transport and fate - understand the transport and fate of mercury from release to the receptor.